WO2024255975A1 - Procédé de lubrification d'un grand moteur à deux temps à l'aide de variations de pression contrôlées dans un rail commun - Google Patents

Procédé de lubrification d'un grand moteur à deux temps à l'aide de variations de pression contrôlées dans un rail commun Download PDF

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Publication number
WO2024255975A1
WO2024255975A1 PCT/DK2024/050040 DK2024050040W WO2024255975A1 WO 2024255975 A1 WO2024255975 A1 WO 2024255975A1 DK 2024050040 W DK2024050040 W DK 2024050040W WO 2024255975 A1 WO2024255975 A1 WO 2024255975A1
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WIPO (PCT)
Prior art keywords
lubricant
pressure
injection
cylinder
injector
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PCT/DK2024/050040
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English (en)
Inventor
Bjørn Christian DUEHOLM
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Hans Jensen Lubricators AS
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Hans Jensen Lubricators AS
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Priority to KR1020267000197A priority Critical patent/KR20260022377A/ko
Priority to CN202480037297.0A priority patent/CN121263591A/zh
Publication of WO2024255975A1 publication Critical patent/WO2024255975A1/fr
Anticipated expiration legal-status Critical
Pending legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
    • F01M1/00—Pressure lubrication
    • F01M1/08—Lubricating systems characterised by the provision therein of lubricant jetting means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
    • F01M1/00—Pressure lubrication
    • F01M1/14—Timed lubrication
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
    • F01M1/00—Pressure lubrication
    • F01M1/16—Controlling lubricant pressure or quantity
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
    • F01M1/00—Pressure lubrication
    • F01M1/08—Lubricating systems characterised by the provision therein of lubricant jetting means
    • F01M2001/083—Lubricating systems characterised by the provision therein of lubricant jetting means for lubricating cylinders

Definitions

  • the present invention relates to a large combustion engine, for example large slow- running two-stroke engine, and a method of lubricating such engine and use thereof.
  • the invention relates to a large slow-running two-stroke engine comprising a cylinder with a reciprocal piston inside and with a lubricant system comprising
  • a lubricant supply including a lubricant pump that raises the pressure of the lubricant to a lubricant pressure which is a typical range of pressure for spray injectors,
  • each injector comprises
  • a nozzle with a nozzle aperture extending into the cylinder configured for injecting lubricant from the inlet port into the cylinder in the injection phase.
  • each injector comprises an adjustable valve at the nozzle for opening and closing for flow of lubricant to the nozzle aperture in the injection phase.
  • the method relates to the lubricating of such large slow-running two-stroke engine. More specific to a method of lubricating a large slow-running two-stroke engine comprising a cylinder with a reciprocal piston inside and with a system comprising
  • a lubricant supply including a lubricant pump, - a plurality of lubricant injectors distributed along a perimeter of the cylinder for injection of lubricant into the cylinder at various positions on the perimeter during injection phases,
  • each injector comprises
  • adjustable means to the extent that it can be controlled how much we pull the needle and how long it must be open. However, it is also possible to use other types of valves.
  • the engine may further comprise
  • the engine may further comprise
  • the lubrication may be effected as jet injection which is an injection where lubricant in metered quantity is injected as a compact jet into the liner of a cylinder or into the piston ring pack. This is also called pulse lubrication.
  • the lubrication may be effected as a spray injection where lubricant under hight pressure is injected into the combustion chamber.
  • a fine mist of the lubricant is injected into the cylinder, preferably in the combustion chamber.
  • the lubricant is provided as a mist of atomized droplets.
  • the injector for spray injection is called spray injector.
  • a specific spray injection is SIP injection.
  • the injector for SIP injection is called SIP injector. The SIP injection is explained in further detail below.
  • a lubricant injector for a marine engine is disclosed in EP1767751, in which a non-retum valve is used to provide the lubricant access to the nozzle passage inside the cylinder liner.
  • the non-retum valve comprises a reciprocating spring-pressed ball in a valve seat just upstream of the nozzle passage, where the ball is displaced by pressurised lubricant.
  • the ball valve is a traditional technical solution, based on a principle dating back to the start of the previous century, for example as disclosed in GB214922 from 1923.
  • An alternative and relatively new lubrication method, compared to traditional lubrication, is commercially called Swirl Injection Principle (SIP).
  • the injectors comprise an injector housing inside which a reciprocating valve member is provided, typically a valve needle.
  • the valve member for example with a needle tip, closes and opens the lubricant’s access to a nozzle aperture according to a precise timing.
  • a spray with atomized droplets is achieved at a pressure of, typically, 35-40 bar.
  • the oil pressure is less than 30 bar and often less than 10 bar in systems working with compact oil jets that are introduced into the cylinder.
  • the high pressure of the lubricant is also used to move a spring-loaded valve member against the spring force away from the nozzle aperture such that the highly pressurised oil is released therefrom as atomized droplets.
  • the ejection of oil leads to a lowering of the pressure of the oil on the valve member, resulting in the valve member returning to its origin and remaining there until the next lubricant cycle where highly pressurized lubricant is supplied to the lubricant injector again.
  • each injector comprises one or more nozzle apertures for delivering lubricant jets or sprays into the cylinder from each injector.
  • SIP lubricant injector systems in marine engines are disclosed in international patent applications W02002/35068, W02004/038189, W02005/124112, W02010/149162,
  • a spray injection need not to be precisely controlled in the same extent as SIP injection.
  • a spray injection need not to use the scavenging air swirl inside the cylinder for distributing the atomized droplets of lubricant on the cylinder liner.
  • the HJL Smartlube 4.0 system is a unique combination of compact design and advanced functionality.
  • the system comprises one or two high pressure units for delivering the lubricant oil to the injectors.
  • the high-pressure unit comprise a pump which through a common rail is connected with all injectors in the engine.
  • each injector is controlled independently by control signals received from the controller.
  • cavitation in the nozzle is formation of vapour cavities inside the liquid due to evaporation. Cavitation in the nozzle influences the atomization of the liquid because it introduces pronounced disturbances in the liquid stream, which destabilizes the jet. In the field of fuel injection, such cavitation in the nozzle has been intensively studied, however, there are also a few studies on cavitation in lubricant injectors.
  • cavitation design advantageously is part of the considerations for optimising the spray injection, in particular for SIP injection.
  • cavitation has not been used in practice for lubricant injection in large marine engines, neither for jet injection nor for spray injection, e.g. SIP injection.
  • the parameters for spray injection, in particular SIP injection have been outside the range where cavitation is achieved.
  • EP 0049603 A2 describes a system for providing lubricant to a low speed ignition machine.
  • this document teaches the use of lubrication timed in order to be arranged between the piston rings.
  • the document only relates to control the amount of lubricant based on the power developed. There is no mention of controlling and varying the pressure depending on the load on the engine.
  • the document does not specify the use of a pressure in the range for SIP injection.
  • WO 2023/088526 describes a large combustion engine and a method described in the introductory paragraphs. It teaches that this system uses the lubricant with a pressure in the range for SIP injection. However, this document does not teach that a controller arranged for controlling and varying the pressure in the lubricant supply conduit.
  • the objective is the objective to improve spray lubrication with spray injectors used in a common rail system in large combustion engines, for example in a large slow-running two-stroke engine. Further, the objective is to improve SIP lubrication with spray injectors in form of SIP injectors.
  • a further objective of the invention is to provide a system in which a variation in the pressure is used to control the degree of atomisation and thus the size of the lubricant droplets in the spray.
  • the method according to the invention may also be used in large four-stroke combustion engines, for example marine engines or combustion engines for power plants.
  • a large combustion engine for example slow-running two-stroke engine, described by way of introduction and as defined in the preamble of claim 1 and which large combustion engine is peculiar in that he controller is arranged for controlling and varying the pressure in the lubricant supply conduit within a desired pressure range in the range of 10 bar to 400 bar, preferably a range of 25 bar to 100 bar, optionally 30 to 80 bar.
  • a method according to the invention for lubricating a large combustion engine described by way of introduction and as defined in the preamble of claim 7 and which method is peculiar in that the method comprises the step of: with the controller varying and controlling the pressure in the lubricant supply conduit within a desired pressure range in the range of 10 bar to 400 bar, preferably a range of 25 bar to 100 bar, optionally 30 to 80 bar.
  • the lubricant supply conduit is preferably a common rail.
  • the lubricant supply is preferably a high-pressure unit.
  • the high-pressure unit preferably comprises a pump.
  • the lubricating supply system is preferably the HJL Smartlube 4.0 system.
  • the invention may also be used in a lubricating principle in engines being modified in that multiple lubricant supply conduits are substituted by a single common lubricant supply conduit. Then the high-pressure unit feeds lubricant to the injectors by a “common rail” system in which all injectors of an engine cylinder, or a subgroup of injectors for a single engine cylinder, are receiving lubricant through the single common lubricant supply conduit in common and simultaneously.
  • a return line for back flow of lubricant from the injectors.
  • the large two-stroke engine comprises a cylinder with a reciprocal piston inside and with a plurality of lubricant injectors distributed along a perimeter of the cylinder for injection of lubricant into the cylinder at various positions on the perimeter during injection phases.
  • the engine is a marine engine or a large engine on a power plant.
  • the engine is burning fuel oil.
  • injection phase is used for the time during which lubricant is injected into the cylinder by the injector.
  • injection cycle is used for the time it takes to inject lubricant by the injector into the cylinder and until the next injection. This terminology is in line with the above-mentioned prior art.
  • injector is herein used for a lubricant injection valve system comprising a housing with a lubricant inlet and one single injection nozzle with a nozzle exit from which the lubricant leaves the nozzle into the cylinder as a spray, the nozzle exit having an exit aperture with an exit size S.
  • the exit aperture is circular with a diameter D, in which case the diameter D is a measure for the size S. If the exit aperture deviates from a circular shape, a potential measure for the size S is the aperture area or an averaged diameter; the latter being useful in case of slight oval or elliptical deviation from a circle.
  • the cross-sectional dimension is an equivalent diameter calculated as twice the square root of the ratio between the cross-sectional area and the number Pi ⁇ 3.14.
  • the nozzle has one or more, typically not more than two, nozzle exits.
  • the nozzle comprises a spray hole, formed as a channel with a length L, for example between 0.5 and 1 mm, one end of which forms the nozzle exit.
  • nozzle comprises a sac hole for flow of lubricant to the spray hole that extends from the sac hole to the nozzle exit.
  • the central longitudinal axis of the spray hole has an angle with a central longitudinal axis of the sac hole, for example in the range of 30 to 90 degrees.
  • the cross-sectional area of the sac hole perpendicular to its central longitudinal axis is often larger than the cross-sectional area of the spray hole perpendicular to its central longitudinal axis.
  • a controller comprises a computer or is electronically or wirelessly connected to a computer.
  • the computer is configured for monitoring parameters for the actual load and motion of the engine.
  • the controller controls the amount and timing of the lubricant injection by the injectors during an injection phase.
  • the controller is configured to control the lubricant pressure and optionally also the temperature of the lubricant in the common rail.
  • cavitation is established in the lubricant oil in the injector.
  • cavitation has been found beneficial for spray formation of lubricants. It has surprisingly been found that it is possible to improve the distribution of droplets in the spray for lubricating the cylinder wall.
  • Q is the volume flow
  • C d is the discharge coefficient
  • zl 0 is the area of the restriction
  • AP is the pressure difference over the restriction
  • p is the density of the fluid
  • the cavitation number For the oil to cavitate, the cavitation number must be close to or below 1.
  • the cavitation number is shown in (2).
  • P a is the ambient pressure (pressure of the cylinder when injection happens)
  • P v is the vapour pressure of the fluid
  • p is the density of the fluid
  • V is the velocity of the fluid.
  • P a Changes a bit with the load of the engine
  • p changes a bit with the temperature, so since these influences are quite small, the largest influence on the cavitation number is the velocity of the oil.
  • Q A • V it can be seen from (1) that the cavitation number must decrease with increasing AP.
  • t is the time constant in the exponential decay of the velocity of the particle due to drag
  • U is the velocity of the particle
  • I is the characteristic length of the shape the particle has, which for a sphere would be the diameter.
  • the present invention is based on a simulation-based investigation of how the cylinder oil feed rate can be reduced.
  • the model development is based on the only common-rail cylinder lubrication system for large two-stroke marine diesel engines explained in “N. Kristensen, 2019, “HJ Common Rail Lubrication System”, CIMAC Congress”.
  • the injectors are operated on the swirl injection principle, for example as explained in S. Lauritsen, J. Dragsted, and B. Buchholz, 2001, “Swirl Injection Lubrication - a New Technology To Obtain Low Cylinder Oil Consumption Without Sacrificing Wear Rates,”, CIMAC congress pp. 921-932, where oil is injected in an upwards direction along the cylinder liner before the piston passes in the compression stroke.
  • the aim for the current study is therefore to develop and validate a model for investigating the swirl injection principle. To demonstrate the simulation-based investigation, a numerical framework is required, which is explained below.
  • the simulation performed is a computational fluid dynamics model.
  • the governing equations of the problem are continuity (4), momentum (5), energy (6) and species (7):
  • Equation 3-7 p is density, U is the velocity vector, p is pressure, g is the acceleration of gravity, h is enthalpy, q is heat flux, Y t is species mass fraction, p e ⁇ is the effective dynamic viscosity, v is the kinematic viscosity I is the identity matrix and T is the shear stress tensor.
  • the turbulence model employed is the k — e model disclosed in “Launder B and Spalding D. The numerical computation of turbulent flows. Computer Methods in Applied Mechanics and Engineering 1974; 3(2): 269-289. DOI: 10.1016/0045- 7825(74)90029-2” governed by the following equations: where k is the turbulent kinetic energy, e is the turbulent kinetic energy dissipation rate,
  • Particles are injected into the scavenging flow in the simulation and the way they move are determined by the Newton’s second law.
  • the buoyancy force is calculated as shown in (13)
  • p p is the density of the particle
  • p is the density of the scavenging air
  • g is the gravitational acceleration
  • V p is the volume of the particle.
  • Equation (12) is solved for each time step in the simulation and for every particle and thus having a small CFL number will give a good approximation of the exponential decay of particle velocity due to drag.
  • the initial velocity of the particles when they enter the cylinder was determined experimentally using the Bosch rate of injection method: “Bosch W.
  • the fuel rate indicator A new measuring instrument for display of the characteristics of individual injection. SAE Technical Papers 1966; DOI: 10.4271/660749” A result of those measurements is shown in Fig. 10.
  • the mass flow does not instantaneously rise when the valve is opened. This is mainly due to the speed that the needle moves with. Because the mass flow does not instantaneously rise, the first oil that is injected, is not injected as a spray.
  • the simulations are performed with two different initial droplet size distributions shown in Fig. 11 and Fig. 12.
  • the two distributions have quite a different shape, but the key difference is how many small droplets they each contain.
  • the one in Fig. 12 has many very small drops, and the one in Fig. 11 is normally distributed, but with a median of approx. 150 pm, which is significantly higher than the one in Fig. 12.
  • the two droplet size distributions are used as input in a simulation model of the scavenging air in a cylinder.
  • the simulation model can predict how large a proportion of the drops hit the wall of the cylinder.
  • Fig. 13 An example of a distribution of oil droplets is shown in Fig. 13.
  • Fig. 14 An illustration of the of the droplets which do not reach the cylinder wall.
  • the blue particles illustrate droplets in the scavenging air, and which do not reach the cylinder wall.
  • the droplet size is inversely proportional to the pressure behind the needle in the injector. So, it will be advantageous to vary the pressure in the common rail when there is a change in the load on the engine and thereby achieve greater adhesion of the droplets to the cylinder wall.
  • Fig. 11 The difference between Fig. 11 and Fig. 12 distribution is to illustrate through simulation how the small droplets follow the streamlines closely and therefore never end up on the wall . Where the larger droplets that initially have a traj ectory towards the cylinder wall are affected, but not to a degree where they never hit the wall.
  • the inertia of the droplets must be affected or the flow in the cylinder must be changed.
  • the flow in the cylinder changes with the change in load of the engine both in terms of velocity and in terms of density both present in (14).
  • the injection pressure can be used to affect the initial Stokes number of the droplets and as the simulations show.
  • the injector For the injector to be able to quickly operate for the intended operation of the injector, it is important that the injector can be operated in the given parameter span.
  • the method according to the invention involves lubricating a large slow-running two- stroke engine comprising a cylinder with a reciprocal piston inside and with a system comprising
  • a lubricant supply comprising a high-pressure pump
  • controller for controlling the amount and timing of the lubricant injection by at least one of the lubricant injectors
  • each injector comprises
  • the method may comprise
  • the control signal to the lubricant supply may be used
  • valve for regulating a valve arranged at the high-pressure pump and connecting the high- pressure pump with the lubricant supply conduit.
  • the output of high- pressure pump is kept constant, and the regulation of the valve is used for regulating the pressure in the lubricant supply conduit to the desired pressure.
  • the valve is connected to the pressure side and suction side of the high-pressure pump.
  • the valve may relieve the pressure as it is connection to the suction side of the high-pressure pump or to a return line to the lubricant supply.
  • the control of the pressure in the lubricant supply conduit makes is possible to obtain the desired effect in form of ensuring that a large part of the lubricant oil hits the surface of the cylinder wall by adjusting the pressure in the common rail in order to influence on the size of the droplets.
  • the controller controls and adjust the pressure in the lubricant supply conduit based on measurement of engine load and actual pressure in the lubricant supply conduit.
  • the controller may control the adjustable valve and regulates the stroke length of a valve member in form of a plunger, whereby the lubricant amount is variably adjustable between injection phases by a stroke length adjustment mechanism.
  • the plunger is not fully retracted to the maximum possible retraction position adjustment is obtained.
  • the stroke of the plunger is always to the same position, for example the same most-forward position, varying the retraction position of the plunger after retraction regulates the stroke length.
  • the controller may be built into the injector or may be connected to the injector and the flowmeter by wiring or in a wireless way.
  • the controller may also be arranged for controlling the lubricant type used.
  • the maximum possible retraction position of the plunger is the most rearward possible position at maximum distance from the nozzle aperture but it is possible that the plunger is held at a distance from the most rearward possible position.
  • the injection amount for the next injection is regulated, as the stroke length is reduced relatively to the maximum possible retraction position.
  • the effect is similar to the screw-adjustable end-stop in W002/35068, however, the stroke length adjustment mechanism can be provided centrally and remotely from the injector, which is in contrast to the injector of W002/35068.
  • the engine according to the present invention may comprise a hydraulically driven inlet-valve system wherein each injector comprises
  • a lubricant inlet port flow-connected to the lubricant supply conduit for receiving lubricant from it;
  • outlet-valve system is configured for opening for flow of lubricant from the front chamber through the outlet-valve system and to the nozzle aperture during an injection phase upon pressure rise above a predetermined pressure limit in the front chamber and at the outlet-valve system and configured for closing the outlet-valve system after the injection phase;
  • the engine further comprises a stroke length adjustment mechanism for variably adjusting the stroke length of the reciprocal hydraulic-driven actuator-plunger.
  • the stroke length adjustment mechanism is configured for variable adjustment of the amount of pressure-liquid that is drained from the pressure chamber between injection phases.
  • variable adjustability is similar to the screw-adjustable end-stop in W002/35068, however, the stroke length adjustment mechanism can be provided centrally and remotely from the injector, which is in contrast to the injector of W002/35068.
  • the stroke length adjustment mechanism comprises a pressure regulator for variably regulating an idle-pressure in the pressure chamber between the injection phases, wherein the idle-pressure is lower than the predetermined limit for only partly counteracting the spring-load from the actuator-plunger spring on the actuator-plunger and thereby variably adjusting the retracted position for the actuator-plunger.
  • the outlet- valve system closes off forback-pressure from the cylinder and also prevents lubricant to enter the cylinder unless the outlet-valve is open.
  • the outletvalve system assists in a short closing time after injection, adding to precision in timing and volume of injected lubricant.
  • the engine comprising a hydraulically driven inlet-valve system may be operated according to a method comprising the stroke length adjustment mechanism is configured for variable adjustment of the amount of pressure-liquid that is drained from the pressure chamber between injection phases and wherein the method comprises adjusting the stroke length between injection cycles by adjusting the amount of pressure-liquid that is drained from the pressure chamber after the injection phase.
  • the engine and the method comprising the hydraulically driven inlet-valve system known from WO 2019/114905 differs as it comprises a pressure gauge.
  • the pressure gauge shall be used for measuring the pressure in the lubricant supply conduit.
  • the engine according to the present invention may also comprise an electrically driven inlet-valve system wherein each_injector comprises - a lubricant inlet port for receiving lubricant from a lubricant supply conduit;
  • outlet-valve system at the nozzle for opening and closing for flow of lubricant to the nozzle aperture during an injection cycle; the outlet-valve system being configured for opening for flow of lubricant to the nozzle aperture during an injection phase upon pressure rise above a predetermined limit at the outlet-valve system and for closing the outlet-valve system after the injection phase.
  • each injector may comprise an electrically-driven inlet-valve system electrically connected to the controller and arranged between the lubricant inlet port and the nozzle for regulating the lubricant that is dispensed through the nozzle aperture by opening or closing for lubricant flow from the lubricant inlet port to the nozzle in dependence of an electrical controlsignal received from the controller; wherein the inlet-valve system is arranged upstream of and remotely from the nozzle and upstream of and remotely from the outlet-valve system.
  • the inlet-valve system may comprise an inlet non-return valve with an inlet-valve member pre-stressed against an inlet-valve seat by an inlet-valve spring and arranged for throughput of lubricant from the lubricant inlet port to the outlet-valve system upon displacement of the inlet-valve member from the inlet-valve seat against force from the inlet-valve spring; wherein the inlet-valve system further comprises an electrically-driven rigid displacement-member for displacing the inlet-valve member from the inlet-valve seat during lubricant injection.
  • each of the injectors comprises an electrically-driven inlet-valve system electrically connected to the controller and arranged between the lubricant inlet port and the nozzle for regulating the lubricant that is dispensed through the nozzle aperture by opening or closing for lubricant flow from the lubricant inlet port to the nozzle in dependence of an electrical control-signal received from the controller.
  • the inlet-valve system is arranged upstream of and remotely from the nozzle, and it is also arranged upstream of and remotely from the outlet-valve system.
  • the inlet-valve system of the injector doses the amount of lubricant for injection by the time the inlet-valve system stays open for the injection phase. The time is determined by the controller.
  • the engine comprising an electrically-driven inlet-valve system may be operated according to a method comprising sending an electrical control signal from the controller to the electrically-driven inlet-valve system for starting an injection phase, and as a consequence thereof causing flow of lubricant from the lubricant supply conduit through the lubricant inlet port, through the inlet-valve system, and into a conduit that flow-connects the inlet-valve system with the outlet-valve system, by the lubricant flow into the conduit increasing pressure in the conduit and at the outlet-valve system, by the pressure rise causing the outlet-valve system to open for flow of lubricant from the conduit to the nozzle aperture and injecting lubricant into the cylinder through the nozzle aperture; at the end of the injection phase, changing the electrical control signal from the controller to the inlet valve system and causing the inlet-valve system to close for lubricant supply from the lubricant inlet port to the conduit.
  • the engine and the method comprising the electrically driven inlet-valve system is generally known from WO 2019/114903.
  • the engine is peculiar in that the lubricant system is chosen from mechanically driven systems, hydraulically driven systems and commonrail systems.
  • the principle according to the invention is flexible and may be used in different lubrication systems.
  • the engine is peculiar in that the pressure gauge is provided in the lubricant supply conduit connected to the injector.
  • the pressure gauge may be arranged immediately in front of the inlet port of a single injector or may alternatively be arranged in a common supply conduit for more injectors, e.g., injectors in a single cylinder.
  • the method comprises that the regulation of the amount of lubricant is controlled by a feedback control/regulation, for example a PID regulation or a more sophisticated model-based regulation.
  • the method comprises that the method involves storing regulation values in a database in the controller.
  • the method and the engine according to the invention is especially suitable for use for spray injection, in particular SIP injection into the cylinder of a large marine engine or combustion engine for a power plant at a lubricant pressure in the range of 10 bar to 400 bar, preferably a range of 25 bar to 100 bar.
  • the method is also suitable for lubrication with a combination of spray lubrication, in particular SIP injection and injection into the ring pack.
  • the injection into the ring pack may be a lubricant spray or a compact lubricant jet.
  • Especially the method and the engine according to the invention is especially suitable for use for SIP injection with an injector of a type generally described in WO 2012/126473 and which is also known as Hans Jensen Lubricators E-sip injector.
  • the term “regulate” refers to a situation where the lubricant amount is amended in order to correspond to a desired amount when the engine is in service.
  • adjust refers to the situation where the lubricant amount is amended when the injectors are calibrated.
  • injector is used for an injection valve system comprising a housing with a lubricant inlet and one single or more injection nozzles with a nozzle aperture as a lubricant outlet and with a movable valve member inside the housing, which opens and closes access for the lubricant to the nozzle aperture.
  • the injector has a single nozzle that extends into the cylinder through the cylinder wall, when the injector is properly mounted, the nozzle itself, optionally, has more than a single aperture.
  • nozzles with multiple apertures are disclosed in WO2012/126480.
  • injection-phase is used for the time during which lubricant is injected into the cylinder by an injector.
  • injection-phase is used for the time between injection-phases.
  • idle state is used for the state of a component in the idle-phase.
  • idle-phase position or orientation is used for the position or orientation of a movable component when in the idle state during the idle-phase, which is in contrast to an injection-phase position.
  • injection cycle is used for the time it takes to start an injection sequence and until the next injection sequence starts.
  • the injection sequence comprises a single injection, in which case the injection cycle is measured from the start of the injection-phase to the start of the next injection-phase.
  • the injection sequence comprises multiple injections, for example multiple injections above the piston before the piston passes the injectors on its way to the TDC, for example a first injection with one lubricant followed by another injection of another lubricant, and potentially further lubricants and/or additives.
  • Such double or multiple injections leads to oil mixing in the cylinder before the piston reaches the TDC.
  • timing of the injection is used for the adjustment of the start of the injectionphase by the injector relatively to a specific position of the piston inside the cylinder.
  • frequency of the injection is used for the number of repeated injections by an injector per revolution of the engine. If the frequency is unity, there is one injection per revolution. If the frequency is 1/2, there is one injection per every two revolutions. This terminology is in line with the above-mentioned prior art.
  • pressurized lubricant is used for lubricant provided at a pressure high enough that it can be used for injection as a jet or spray into the cylinder.
  • the latter is in contrast to oil injection by quills between piston rings.
  • the pressure depends on the purpose and form of injection and is typically above 10 bar.
  • spray injection in particular SIP injection, the pressure is typically higher, for example above 25 bar.
  • flowmeter is used for a component which is able to measure a flow independent of the method used, e.g. pressure difference, viscosity, temperature, amount.
  • the large engine for example slow-running two-stroke engine, optionally a marine engine or engine for a power plant, comprises a cylinder with a reciprocal piston inside and with a plurality of lubricant injectors fixed to a wall of the cylinder and extending through the cylinder wall.
  • the injectors are distributed along a perimeter of the cylinder and configured for injection of lubricant into the cylinder at various positions on the perimeter during injection-phases.
  • the large engine such as slow-running two-stroke engine, is a marine engine or a large engine in power plants.
  • the engine is burning diesel or gas fuel, for example natural gas fuel.
  • the engine comprises also a lubricant supply with a pressurized lubricant, typically pressurized by a lubricant feed pump.
  • the engine comprises more than one lubricant supply with correspondingly more than one type of lubricant, and correspondingly more than one lubricant feed pump.
  • Each of the plurality of injectors is connected with each of its lubricant inlets to lubricant supply through a corresponding lubricant supply conduit.
  • Each lubricant supply includes a potential pressure source, typically a lubricant pump, which raises the pressure of the corresponding lubricant to an adequate level. For the described system, it suffices to provide a constant lubricant pressure at the corresponding lubricant inlet of the injector.
  • the injectors are configured for the type of lubricant to be injected.
  • the inlet can be used to provide and add not only lubricants but also potential additives.
  • the injector optionally has more inlets of which one is used for lubricants, such as lubrication oils, and one is used for an additive.
  • the engine further comprises a controller.
  • the controller is configured for controlling the amount and timing of the injection of the lubricant by the plurality of injectors.
  • the injection frequency is controlled by the controller.
  • the controller is electronically connected to a computer or comprises a computer, where the computer is monitoring parameters for the actual load and motion of the engine. Such parameters are useful for the control of optimized injection.
  • the controller is provided as an add-on system for upgrade of already existing engines.
  • a further advantageous option is a connection of the controller to a Human Machine Interface (HMI) which comprises a display for surveillance and input panel for adjustment and/or programming of parameters for injection profiles and optionally the state of the engine.
  • HMI Human Machine Interface
  • Electronic data connections are optionally wired or wireless or a combination thereof.
  • the injector comprises a lubricant inlet for receiving the lubricant from a lubricant supply conduit for injection of the lubricant into the cylinder.
  • the lubricant inlet of the injector is connected to the lubricant supply though the lubricant supply conduit.
  • the injector has a lubricant flow path from the lubricant inlet to the at least one nozzle for lubricant flow from the lubricant inlet through the at least one nozzle into the cylinder.
  • the injector comprises one nozzle or more than one nozzle, for example two nozzles.
  • Each nozzle has a nozzle aperture, extending into the cylinder for lubricant injection in an injection-phase.
  • a nozzle has more than a single aperture.
  • nozzles with multiple apertures are disclosed in WO2012/126480.
  • the injector comprises a single nozzle with a single nozzle aperture.
  • each injector comprises an internal actuator-driven valve system in the lubricant flow path, wherein the valve system is configured for selectively switching from the idle state without injection to an injection state with injection of the lubricant, into the cylinder through the at least one nozzle in the injection-phase in dependence of the received injection-phase signals.
  • Each injector comprises an actuator for driving the valve system.
  • the actuator is functionally connected to the controller and configured for being activated by the controller for selectively driving the valve system and causing injection of the lubricant under control by the controller as a consequence of the activation of the actuator by the controller.
  • the valve system under control by the controller, is used for selecting which amount and timing to be used for injections and in which sequence.
  • the actuator is activated by the controller for starting an injection-phase with the lubricant.
  • the valve system is caused to open for flow of the lubricant through the flow path and injecting the lubricant into the cylinder.
  • the actuator is caused to close the valve system and stop lubricant supply.
  • the engine comprises a lubricant supply conduit containing lubricant at a desired pressure and being connected to the abovementioned E sip injectors.
  • the injector is provided with integrated opening/closing valve, preferably a solenoid valve, such that both piping and drawing of cables are appreciably simplified by only having one common supply line of pressurised lubricating oil (without need for a return line) provides that the dosing becomes proportional with the time where the opening/closing solenoid valve is open.
  • opening/closing valve preferably a solenoid valve
  • there is a separate local control box which is used for opening/closing the injector based on signals from the engine/control unit of the ship.
  • An electromechanically regulated injector designed for cylinder lubrication of large diesel engines entail advantages in relation to prior art lubricating systems. System wise it can regulate individually with regard to lubricating oil amount and timing.
  • the function is only dependent on a control box which can control each single injector separately or together with regard to timing and opening time. This can occur independently of other opening/closing valves and is only limited by the speed at which the opening/closing valve in an injector can execute the opening/closing cycle.
  • the measured flow is used for controlling the delivered amount in relation to the planned amount.
  • an associated local control box can correct the opening time for magnet valve(s) for the associated injector or injectors.
  • the engine comprises a lubricant supply conduit containing lubricant at a first pressure and a pressure-control conduit containing pressure-liquid at a pressure higher than the first pressure.
  • the injector comprises an internal hydraulic-driven pumping system where the pressure-liquid is used for driving the pumping system inside the injector housing by which the lubricant is pressurized in the injector and ejected therefrom.
  • the injector comprises a lubricant inlet port, flow-connected to the lubricant supply conduit for receiving lubricant from it for injection into the cylinder.
  • the injector also comprises a pressure-control port, flow-connected to the pressure-control conduit for receiving pressure-liquid therefrom in the injection phase.
  • the injector comprises the front chamber inside the injector between the lubricant inlet port and the outlet-valve system for receiving and accumulating a pre-determined volume of lubricant from the inlet port prior to an injection phase.
  • a pressure chamber in the injector is in communication with the pressure-control port for receiving the pressure-liquid from the pressure-control port in the injection phase.
  • the pressure-liquid in the pressure chamber drives a pumping system in the injector.
  • the pumping system comprises a reciprocal hydraulic-driven actuator-plunger in contact with the pressure chamber and pre-stressed by a spring-load from an actuatorplunger spring and configured for being driven, for example in a direction towards the nozzle, by the pressure-liquid in the pressure chamber in the injection phase, by which it is causing pressure rise in the lubricant in the front chamber above the predetermined limit and causes pumping of this predetermined lubricant volume through the non-re- tum valve and the nozzle aperture into the cylinder.
  • the injection phase comprises multiple injections, for example multiple injections above the piston before the piston passes the injectors on its way to the TDC, for example a first injection with lubricant followed by another injection of the lubricant, and potentially further lubricants and/or additives.
  • Such double or multiple injections especially when in SIP operation, leads to oil mixing in the cylinder before the piston reaches the TDC.
  • the variety of selecting lubricant for injection, its amount and its timing as controlled by the controller makes a high variety of injection sequences possible, for example combinations of at least two of:
  • the actuator is an electrically controlled actuator and is electrically connected to the controller by an electrical connection for receiving injection-phase signals from the controller, the injection-phase signals indicating the timing for the injection.
  • an electrical control signal is sent from the controller to each of the injectors for starting an injection-phase with the lubricant.
  • the valve system opens for flow of the corresponding lubricant through the flow path and injects it into the cylinder.
  • the electrical control signal from the controller to the injector is changed, causing the valve system to close for lubricant injection and return to the idle state.
  • the actuator comprises an electrical solenoid arrangement with a stationary solenoid part and a movable solenoid part.
  • the valve system is connected to the movable solenoid part for being driven by the actuator upon electrical excitation of the solenoid, wherein the solenoid is configured for excitation by the injection-phase signals from the controller.
  • a solenoid coil should be understood as “at least one solenoid coil”, as it is possible and, in some cases, advantageous to use more than one coil, for example two or three coils.
  • the term “signal” from the controller is used here for an electrical current that flows from the controller to the injector.
  • the signal itself can be used for driving the actuator, for example an electromechanical actuator, if the current is sufficiently strong.
  • the injector could comprise an electro- switch where the signal from the controller opens for flow of a current sufficiently strong to drive the actuator.
  • the signal lines from the controller to the electro- switch can be accomplished by very thin wiring.
  • the term “signal” also is used for a wireless signal.
  • the actuator is a hydraulic or pneumatic actuator.
  • Such hydraulic or pneumatic actuator in the injector is, optionally, also electrically controlled.
  • an electrical signal from the controller to the injector causes an electromechanical actuatorvalve of the inj ector to open for hydraulic or pneumatic flow into the actuator for driving the valve system hydraulically or pneumatically.
  • an electrical signal from the controller to the injector causes an electromechanical actuator-valve to open for hydraulic or pneumatic flow into the actuator for driving the actuator itself, which then, in turn, by a mechanical connection drives the valve system.
  • the valve system is configured to select only one injector at a time among multiple injectors for supply of lubricant and for injection thereof. In some embodiment, alternatively or in addition, the valve system is configured to select more than one injector at a time among multiple injectors for supply of lubricant and for injection thereof in order to inject simultaneously multiple lubricants or lubricant in combination with additive.
  • the injector has more than one nozzle, and multiple lubricants and additives can be injected into the cylinder through separate nozzles of the injector. In other embodiments, multiple lubricants and additives are injected into the cylinder through a single nozzle and potentially mixed inside the injector prior to ejection from the nozzle aperture.
  • the injector comprises a base and a rigid, optionally cylindrical, flow chamber, which is rigidly connecting the base with the nozzle for fixing the nozzle inside the cylinder wall when the base is fixed to the cylinder wall. Due to the base being provided at the opposite end of the flow chamber relatively to the nozzle, it is typically located on or at the outer side of the cylinder wall.
  • the injector comprises a flange at the base for mounting onto the outer cylinder wall.
  • the injector comprises a flange provided around the flow chamber. For example, the flange is bolted against the cylinder wall.
  • the base comprises the first and second inlet and the potential further inlets.
  • the flow chamber is hollow and contains the flow path for lubricant flow from the lubricant inlet through the flow chamber and to the nozzle for injection of the lubricant into the cylinder.
  • the valve member is located in the flow chamber or in the base.
  • the actuator is provided outside the cylinder wall when the injector is mounted at the cylinder wall.
  • it is fixed to the base.
  • the injection-phase signal is received by the actuator, causing the actuator to move the valve member in dependence of the injection-phase signal to an injectionphase position or orientation, which leads correspondingly to opening of the flow path for injection of the lubricant into the cylinder.
  • the actuator is mechanically connected to the sei ection- valve member by an actuator extension for driving the valve member by the actuator extension.
  • the operation comprises moving the valve member by the actuator by using the actuator extension.
  • each of the injectors comprises an outlet-valve system at the nozzle configured for opening for flow of lubricant to the nozzle aperture during an injection-phase upon pressure rise above a predetermined limit at the outlet-valve system and for closing the outlet-valve system after the injection-phase when the pressure drops.
  • the outletvalve system closes off for back-pressure from the cylinder and also prevents lubricant to enter the cylinder in the idle-phase between injection-phases.
  • the outletvalve system assists in a short closing time after injection, adding to precision in timing and volume of injected lubricant.
  • the injector comprises a lubricant flow path from the lubricant inlet through the valve system and to the outlet-valve system for flow of the lubricant from the lubricant inlet, through the valve system and the outlet-valve system and out of the injector at the nozzle aperture.
  • the valve system is arranged as part of the injector upstream of and optionally spaced from the nozzle.
  • the valve system is arranged upstream of and spaced from the outlet-valve system.
  • the outlet-valve system comprises an outlet non-return valve.
  • the outlet-valve member for example a ball, ellipsoid, plate, or cylinder
  • the outlet-valve spring acts on the outletvalve member in a direction away from the nozzle aperture, although, an opposite movement is also possible.
  • the method comprises sending an electrical control signal from the controller to the injector and by the control signal causing the injector to open the valve system for flow of lubricant from the lubricant supply conduit through the lubricant inlet, through the valve system, and into a conduit that flow-connects the valve system with the outlet-valve system.
  • the pressure of the lubricant in the lubricant supply conduit is above the predetermined limit that determines the opening of the outlet-valve system in order for the lubricant supply conduit to provide lubricant through the valve system with a pressure sufficiently high to open the outlet-valve system in the injection-phase.
  • the lubricant flow through the valve system and into the conduit between the valve system and the outlet-valve system causes a pressure rise at the outlet-valve system, causing the outlet-valve system to open for flow of lubricant from the conduit to the nozzle aperture by which lubricant is injected into the cylinder through the nozzle aperture.
  • the electrical control signal from the controller is changed, causing the valve system to close again for lubricant supply from the lubricant inlet to the nozzle aperture.
  • the pressure in the conduit decreases again, and the outlet-valve system closes.
  • valve system is regulated under control by the controller, for example by electrical signals from the controller, and the outlet-valve system is activated only by the elevated pressure of the lubricant at the outlet-valve system, once the valve system has opened and caused flow of lubricant at elevated pressure from the lubricant supply conduit to the outlet-valve system.
  • controller for example by electrical signals from the controller
  • outlet-valve system is activated only by the elevated pressure of the lubricant at the outlet-valve system, once the valve system has opened and caused flow of lubricant at elevated pressure from the lubricant supply conduit to the outlet-valve system.
  • the valve system comprises a movable, actuator-driven valve member arranged for moving from an idle-phase position, in which the valve member in the idle-phase blocks the flow path, to an injection-phase position, in which the valve member opens the flow path for flow of lubricant through the flow path in the injection-phase.
  • the valve member is pre-stressed towards an idle- phase position by a valve spring.
  • the injector for driving the movable valve member, comprises a movable and actuator-driven rigid actuator-extension that is connecting the actuator with the valve system and which is used by the actuator for displacing or rotating the valve member from an idle-phase position, in which the valve member blocks the flow path, to an injection-phase position, in which the valve member opens the flow path for flow of a lubricant through the flow path for injection of the lubricant into the cylinder in an injection-phase.
  • the actuator-driven rigid actuator-extension is a pull-push-member for selectively pulling or pushing the valve member in the injection.
  • the actuator extension is a rotational member transferring the driving force from a rotational actuator for example selectively in one direction or the other.
  • the actuator is an electrically controlled actuator, for example an electromechanical actuator.
  • the actuator comprises an electrical solenoid arrangement with a stationary solenoid part and a movable solenoid part and wherein the actuator-extension is connected to the movable solenoid part for being driven by electrical excitation of the solenoid, wherein the solenoid is configured for excitation by the injection-phase signals from the controller.
  • the valve system comprises a linear actuator for driving the actuator-ex- tension.
  • the actuator-extension is connected to the actuator, for example to an arrangement of a solenoid-plunger and solenoid coil, for upon electrical activation of the actuator to drive the actuator-extension, for example pull-push-member for open for flow from the lubricant inlet.
  • the actuator-extension is connected to the solenoid-plunger, whereas the solenoid coil is stationary in the injector.
  • the actuator-extension is connected to the solenoid coil, which is movable together with the actuator-extension.
  • piezo-electric elements can be used for driving the valve member. Such elements are electrically or wireless connected to the controller for being controlled by the controller with respect to when to contract or expand.
  • the valve member is cylindrical and comprises a stationary valve member, which, in turn, comprises a corresponding cylindrical bushing inside which the cylindrical valve member is arranged for displacement along a longitudinal axis of the bushing or arranged for rotation about longitudinal axis of the bushing.
  • cylindrical bushing is used for describing that the bushing has a cylindrical hollow, typically but not necessarily with a circular cross section.
  • the cylindrical valve member fits tightly into the cylindrical hollow of the bushing so that no lubricant can flow between the cylindrical valve member and the cylindrical bushing apart from a potential minimal amount that is only lubricating the valve member inside the bushing and which is negligible as compared to the amount of lubricant injected into the cylinder.
  • the system as described herein has a number of advantages.
  • the mass of movable members that has to be moved during operation is low.
  • the low mass reduces reaction time of the movable objects as compared to prior art systems, why the system implies an increased reaction speed and corresponding precision with respect to timing and amount.
  • the distance from the valve system to the nozzle aperture is typically in the order of the thickness of the cylinder wall or even less.
  • the distance from the valve system to the nozzle aperture is less than 20 cm or even less than 10 cm, which is much shorter than the distance of several meters between a valve and the nozzle in the prior art. This implies that the distance from the valve system to the nozzle exit is extremely short in comparison and the valve system has correspondingly short reaction times and precision.
  • the injector Due to the valve system being inside the injector housing and close to the nozzle, the injector has a short reaction time such that high precision can be achieved for injection timing and time length, the latter translating into volume for injection. Due to the high timing precision and the fast reaction time, the lubricant injection in a single injection- cycle can be done with multiple partial injections. As the injector as described above only has a short and rigid flow channel from the valve system to the nozzle, for example including an outlet-valve system, uncertainties and imprecisions of the injection amount and the timing are minimized in that minute compression and expansion of the oil in the relatively long conduits are avoided as well as expansion of the conduits themselves.
  • a double injection can be made so that two types of lubricant may be mixed in the cylinder, especially when using the SIP principle.
  • the system may only need a single lubricant line to the injectors for lubricant, as there is no need for a return line, which minimizes costs and efforts for installation and minimizes the risk for faults. This is especially so because the engines are large and would require return lines of several meters length. Also, imprecision in time a volume when closing the valve due to dead volume in a potentially return pipe for the lubricant is avoided.
  • the outlet-valve system comprises a non-return valve in or at the nozzle, and the non-return valve comprises a valve member, for example ball, which is spring pressed against a valve seat, a high degree of robustness against failure has been observed.
  • the valve seats tend to be self-cleaning and subject to little uneven wear, especially for valve members being balls, why a high and long-term reliability is provided. Accordingly, the injector is simple and reliable, quick and precise, and easy to construct from standard components with low production costs.
  • the specific valve system is acting fast due to its light-weight components. Furthermore, the components are relatively simple in construction and imply low production costs. In addition to these advantages, the valve system is reliable, robust, and has a low risk for clogging. As the components are subject to relatively small pressure load, the valve system also has a long lifetime.
  • the injectors comprise a nozzle with a nozzle aperture that has a diameter D if the nozzle is circular, or wherein the nozzle has an equivalent diameter D which is two times the square root of the nozzle aperture area divided by pi if the nozzle is not circular; wherein the diameter D is at least 0.1 mm, and are configured for ejecting a spray of atomized droplets, which is also called a mist of oil.
  • a spray of atomized droplets is important in spray lubrication.
  • Such spray of atomized droplets is in particular important in SIP lubrication, where the sprays of lubricant are repeatedly injected by the injectors into the scavenging air inside the cylinder prior to the piston passing the injectors in its movement towards the TDC.
  • the atomized droplets are diffused and distributed onto the cylinder wall, as they are transported in a direction towards the TDC due to a swirling motion of the scavenging air towards the TDC.
  • the atomization of the spray is due to highly pressurized lubricant in the lubricant injector at the nozzle.
  • the pressure is higher than 10 bar, typically between 25 bar and 100 bar for this high-pressure injection.
  • An example is an interval of between 30 and 80 bar, optionally between 35 and 60 bar.
  • the injection time is short, typically in the order of 5-30 milliseconds (msec). However, the injection time can be adjusted to 1 msec or even less than 1 msec, for example down to 0.1 msec. Therefore, imprecisions of only a few msec may alter the injection profile detrimentally, why high precision is required, as already mentioned above, for example a precision of 0.1 msec.
  • Lubricants used in marine engines typically, have a typical kinematic viscosity of about 220 cSt at 40°C and 20 cSt at 100°C, which translates into a dynamic viscosity of between 202 and 37 mPa-s.
  • An example of a useful lubricant is the high performance, marine diesel engine cylinder oil ExxonMobil® MobilgardTM 570VS (or 560VS which is being phased out).
  • Other lubricants useful for marine engines are other MobilgardTM oils as well as Castrol® Cyltech oils.
  • lubricants for marine engines have largely identical viscosity profiles in the range of 40-100°C and are all useful for atomization, for example when having a nozzle aperture diameter of 0.1-0.8 mm, and the lubricant has a pressure of 30-80 bar at the aperture and a temperature in the region of 30-100°C or 40-100°C. See also, the published article on this subject by Rathesan Ravendran, Peter Jensen, Jesper de Claville Christiansen, Benny Endelt, Erik Appel Jensen, (2017) "Rheological behaviour of lubrication oils used in two-stroke marine engines", Industrial Lubrication and Tribology, Vol. 69 Issue: 5, pp.750-753, https://doi.org/10.1108/ILT-03-2016-0075.
  • the movement of the oil droplets is governed by the relationship between the momentum of the droplets and the forces affecting the droplets.
  • the drops' momentum is controlled by their speed and mass, that is
  • buoyancy The two most important forces are buoyancy:
  • the momentum of the droplets must be affected. This can be done by changing either:
  • a pressure variation measured by the pressure gaugein the inj ector is used to calculate the volume flow through the nozzle in experimental tests.
  • the injected amount as a function of ramp time is approximately a straight line, making is easier to accurately dose the correct amount of oil together with the rise and fall times close to 1 ms. For the mass flow of the lubricant oil.
  • the Bosch rate of injection method is capable of predicting the delivered amount of an injection within approximately 5% of the weighted amount for almost the entire tested range of ramp times for the highly viscous fluid used called Hy- draWay HVXA15, which has similar properties to heated cylinder lubrication oil [Ravendran R, Jensen P, De Claville Christiansen J et al. Rheological behavior of lubrication oils used in two-stroke marine engines. Industrial Lubrication and Tribology 2017; 69(5): 750-753. DOL10.1108/ILT-03-2016-0075].
  • FIG. 1 is a sketch of part of a cylinder in a first embodiment of an engine according to the present invention
  • Fig. 2 is a drawing of an embodiment of the injector illustrated in Fig. 1
  • Fig. 3 is a graph illustrating experimental data, and comparison to literature
  • Fig. 4 is a sketch illustrating a further embodiment of a nozzle for the injector illustrated in Fig. 2,
  • Fig. 5 is a sketch corresponding to Fig. 1 of part of a cylinder in a further embodiment of an engine according to the present invention
  • Fig. 6 is a sketch of an embodiment of the injector illustrated in Fig. 5,
  • Fig. 7 is an enlarged section of the inlet-valve housing of the injector illustrated in Fig- 6,
  • Fig. 8 is a sketch corresponding to Fig. 1 of part of a cylinder in a further embodiment of an engine according to the present invention
  • Fig. 9 is a graph illustrating experimental data, and comparison to literature,
  • Fig. 10 is a graph illustrating the relation between time and mass flow
  • Fig. 11 illustrates a first initial droplet size distribution
  • Fig. 12 illustrates a second initial droplet size distribution
  • Fig. 13 illustrates a third initial droplet size distribution
  • Fig. 14 is an illustration of the of the droplets which do not reach the cylinder wall for the distribution illustrated in Fig. 13,
  • Fig. 15 is a partially sketch of a common rail system comprising a common rail, a high- pressure unit with a pump and a valve,
  • Fig. 16 is a sketch of a further embodiment of an injector to be used in a system according to the present invention and illustrated in closed position and
  • Fig. 17 is a sketch of the injector in Fig. 13, however illustrated in open position.
  • FIG. 1 illustrates one half of a cylinder 1 of a large slow-running two-stroke engine, for example marine diesel engine.
  • the cylinder 1 comprises a cylinder liner 2 on the inner side of the cylinder wall 3.
  • the injectors 4 are distributed along a circle with the same angular distance between adjacent injectors 4, although this is not strictly necessary. Also, the arrangement along a circle is not necessary, seeing that an arrangement with axially shifted injectors is also possible, for example every second injector shifted towards the piston’s top dead centre (TDC) relatively to a neighbouring injector.
  • TDC top dead centre
  • Each of the injectors 4 has a nozzle 5 with a nozzle aperture 5’ from which a fine atomized spray 8 with miniature droplets 7 is ejected under high pressure into the cylinder 1.
  • the nozzle aperture 5’ has a diameter of between 0.1 and 0.8 mm, such as between 0.2 and 0.5 mm, which at a pressure of 10-100 bar, for example 25 to 100 bar, optionally 30 to 80 bar or even 50 to 80 bar, atomizes the lubricant into a fine spray 8, which is in contrast to a compact jet of lubricant.
  • the swirl 14 of the scavenging air in the cylinder 1 transports and presses the spray 8 against the cylinder liner 2 such that an even distribution of lubrication oil on the cylinder liner 2 is achieved.
  • This lubrication system is known in the field as Swirl Injection Principle, SIP.
  • the cylinder liner 2 is provided with free outs 6 for providing adequate space for the spray 8 or jet from the injector 4.
  • a lubricant supply conduit 9 - being a common supply conduit - the injectors 4 are connected to the controller 11 by a pressure-control conduit 10.
  • the lubricant supply conduit 9 is used for providing lubricant for injection.
  • the pressure-control conduit 10 provides oil at high pressure to activate an internal pumping system inside the injector 4, which will be explained in more detail in the following.
  • the pressure in the pressure-control conduit 10 is higher than the pressure in the lubricant supply conduit 9.
  • the lubricant pressure in the lubricant supply conduit 9 is in the range of 1-15 bar, for example in the range of 5-15 bar
  • the oil pressure in the pressure-control conduit 10 is in the range 20-100 bar, for example in the range 30-80 bar, optionally 50-80 bar.
  • the controller 11 is connected to a supply conduit 12 for receiving lubricant from a lubricant supply 25, including an oil pump, and a return conduit 13 for return of lubricant, typically to an oil reservoir, optionally for recirculation of lubricant.
  • the lubricant pressure in the supply conduit 12 is higher than the pressure in the return conduit 13, for example at least two times higher.
  • the controller 11 supplies lubrication oil to the injectors 4 in precisely timed pulses, synchronised with the piston motion in the cylinder 1 of the engine.
  • the controller system 11 is electronically by wires or wireless connected to a computer 11’ which controls components in the controller 11 for the lubrication supply.
  • the computer 11’ is part of the controller 11, for example provided inside a single casing with the other components of the controller 11.
  • the computer monitors parameters for the actual state and motion of the engine, for example speed, load, and position of the crankshaft, the latter revealing the position of the pistons in the cylinders.
  • FIG. 2 illustrates an injector 4.
  • the injector 4 comprises an injector housing 4’ with an injector base 21 having a lubricant inlet port 4A for receiving lubricant from the lubricant supply conduit 9 and a pressure port 4B connected to the pressure-control conduit 10 for causing ejection of lubricant by the injector 4.
  • the flow chamber 16 is provided as a hollow rigid rod.
  • the flow chamber 16 is sealed against the injector base 21 by an Ciring 22 and held tightly against the injector base 21.
  • a conduit 16’ is provided as a hollow channel inside the flow chamber 16 from the rear to the front of the flow chamber 16.
  • the conduit 16’ communicates with the lubricant inlet port 4A and with the nozzle 5 through a rear chamber 16 A, a first intermediate chamber 16B, a second intermediate chamber 16C, and front chamber 16D.
  • the injector 4 also comprises an outlet-valve system 15 for regulating the lubricant that is dispensed through the nozzle aperture 5’. Only if the pressure exceeds a predetermined pressure at the outlet-valve system 15, the outlet-valve system 15 opens for ejection of the lubricant into the cylinder 1 of the engine.
  • the outlet-valve system 15 is exemplified as being part of the nozzle 5, although, this is not strictly necessary.
  • the outlet-valve system 15 comprises an outlet non-return outlet-valve 17.
  • an outlet-valve member 18 exemplified as a ball, is prestressed by a spring-load against an outlet-valve seat 19 by an outlet-valve spring 20.
  • the pre-stressed force of the outlet-valve spring 20 is counteracted by the lubricant pressure, and when the pressure gets higher than the spring force, the outlet-valve member 18 is displaced from its outlet-valve seat 19, and the outlet non-return outlet-valve 17 opens for injection of lubricant through the nozzle aperture 5’ into the cylinder 1.
  • the outlet-valve spring 20 acts on the valve member 18 in a direction away from the nozzle aperture 5’.
  • the configuration could be different with respect to the direction of the force of the outlet-valve spring 20 on the outlet-valve member 18 relatively to the nozzle aperture 5’, as long as the non-return outlet-valve 17 is closing for the supply of lubricant to the nozzle aperture 5’ when in an idle state between injection phases.
  • the closing of the non-return outlet-valve 17 in an idle state prevents unintended flow of lubricant from the front chamber 16D through the nozzle aperture 5’ into the cylinder 1 between injection phases.
  • the rear chamber 16A communicates with the inlet port 4 A for receiving lubricant from the lubricant supply conduit 9.
  • the rear chamber 16A communicates with the first intermediate chamber 16B through rear channel 23 A.
  • the first intermediate chamber 16B communicates with the second intermediate chamber 16C through intermediate channel 23B, which is a cylindrical opening around an actuator-member 28, which will be explained below.
  • the second intermediate chamber 16C communicates with the front chamber 16D through front channel 23 C.
  • forward motion is used for motion towards the nozzle aperture 5’ and the oppositely directed motion away from the nozzle aperture 5’ is called “rearward motion”.
  • the front chamber 16D is emptied through the nozzle aperture 5’ by forward motion of a reciprocal plunger-member 29, which is spring-loaded against the forward motion by a helical plunger spring 29B in the second intermediate chamber 16C.
  • the plungermember 29 comprises a channel inlet 24 that leads into front channel 23C, which is an internal channel in the plunger-member 29, for example centrally in the plunger-member 29, as indicated.
  • front channel 23C is closed by a non-retum plunger-valve 26.
  • the nonreturn plunger-valve 26 is exemplified as comprising a plunger-valve ball 26A in a plunger-valve seat 26B, against which the plunger-valve ball 26A is pre-stressed by a plunger-valve spring 26C.
  • Forward motion of the plunger-member 29 is achieved by forward motion of an actuator-member 28, which presses against the head 29A of the plunger-member 29.
  • the actuator-member 28 is pre-stressed in a rearward direction by a helical actuator-spring 28 A in the first intermediate chamber 16B.
  • the actuator-member 28 and the plungermember 29 are separate elements, however, they could also be combined as a single actuator-plunger, for example by having the actuator-member 28 at one end of the single element and the plunger-member 29 at the opposite end.
  • the pressure-control port 4B is provided with pressurized oil, for example in the pressure range of 20-100 bar, the pressurized oil expands the volume of the pressure chamber 27 by pushing on the rear part 28B of the actuator-member 28 and moving the actuatormember 28 forward.
  • the actuator-member 28 presses against the head 29A of the plunger-member 29, the plunger-member 29 moves forward together with the actuatormember 28 against the force of the actuator-spring 28 A and the plunger spring 29B.
  • the forward motion of the plunger-member acts on the lubricant in the front chamber 16D.
  • the lubricant in the front chamber 16D is pressurised to the predetermined pressure limit at which the outlet-valve-system system 15 with the non-return outlet-valve 17 opens for ejection of the lubricant from the front chamber 16D through the nozzle aperture 5’ into the cylinder 1.
  • the oil at the pressure-control port 4B is drained, which causes the actuator-spring 28A and the plunger spring 29B to press back the actuatormember 28 and the plunger-member 29 in a direction away from the nozzle 5.
  • the rearward motion of the plunger-member 29 reduces the pressure in the front chamber 16D, which, in turn, closes the non-return outlet-valve 17 and draws lubricant from the second intermediate chamber 16C through front channel 23 C into the front chamber 16D, as the plunger non-retum valve 26 is opened by the pressure reduction in the front chamber 16D.
  • the non-retum plunger-valve 26 acts as a suction valve because the pressure reduction in the front chamber 16D causes refilling of the front chamber 16D with lubricant by suction through the non-return plunger-valve 26.
  • lubricant in the second intermediate chamber 16C is replenished from the first intermediate chamber 16B, which is turn is filled by lubricant from the rear chamber 16A that received the lubricant through the lubricant inlet port 4A.
  • the lubricant inlet port 4a is provided with lubricant from the lubricant feed conduit 9 at a constant pressure
  • the pressure-control port 4B is provided with pressure-oil from the pressure-control conduit 10 intermittently for each injection-cycle. The pressure at the pressure-control port 4B is raised in the injection phase and reduced in the idle state between injection phases.
  • a full stroke of the plunger-member is achieved by intermittently changing the oil pressure at the pressure-control port 4B between a full pressure and a lower pressure, for example at the pressure of the lubricant in the lubricant supply conduit 9 or even lower.
  • the actuator-member 28 and the plunger-member 29 can be held offset from the most rearward position by adjusting the pressure at the pressure-control port 4B and in the pressure chamber 27 at an offset pressure level that creates a force on the actuator such that the springs 28A and 29B do not fully elongate during rearward motion of the actuator-member 28 and the plunger-member 29 but are kept slightly compressed.
  • the offset pressure level is smaller than the pressure level necessary to cause the non-return outlet-valve 17 to open for injection.
  • the injector 4 can be provided with lubricant at the inlet port 4 A from one lubricant source and with pressure-oil or other pressure-liquid from an entirely different source.
  • the pressure-oil at the pressure-control port 4B is provided from the same source as the lubricant at the inlet port 4A, however, with increased pressure, for example by use of a pressure intensifier.
  • the lubricant supply conduit 9 is communicating with the return line 13. This is also illustrated in FIG. 1 by the solid line 9” which in extension is connected to the supply conduit 9.
  • the controller 11 being an addon unit, the controller 11 would have at least 4 conduit connectors.
  • the controller 11 comprises a return exit line which is connected to the return conduit 13.
  • the return conduit 13 is directly communicating with the supply conduit 9’ and 9.
  • This embodiment is illustrated in FIG. 1 by the dotted alternative line 9’, which in extension is connected to the supply conduit 9.
  • the return conduit 13 in extension of the supply conduit 9 and 9’ provides lubricant directly to the lubricant inlet port 4A of the injectors 4 for injection into the cylinder, and the controller 11 is bypassed.
  • the pressure in the return conduit 13 and the supply conduit 9 is 10 bar.
  • the pressure in the supply conduit 12 is 40 bar.
  • the outlet-valve 15 opens at 37 bar, such that the lubricant is injected at 37 bar.
  • the springs 28A and 29B are configured for pressing the plunger-member 29 and the actuator-member 28 fully back to the rearmost position if the pressure at the pressure-control port 4B in the idle state between injection phases is 10 bar.
  • the pressure-valve is adjustable to a pressure of between 10 and 30 bar, for example 20 bar, well below the 37 bar injection pressure but high enough to provide high enough pressure in the pressure chamber 27 for the actuator-member 28 not returning fully to the most rearward position but keeping a distance from the most rearward.
  • the injection volume is controlled by a flowmeter inserted in the supply line
  • the flowmeter measures flow (mass and/or volume) and is then used for control that the inj ector(s) is/are properly working.
  • the injection system with the injector 4 as described above and the controller 11 are simple to install and replace. It is a relatively low-cost technical solution, albeit robust and stable. Especially, the injection volume is precisely adjustable. Also, the system does not comprise electrical wires to and from the injector 4, which makes it robust against heat, whereas electrical wires are likely to have an insulation layer that melts in heat.
  • the engine differs as it comprises a pressure gauge 35.
  • the pressure gauge may also be called a pressure sensor.
  • the pressure gauge 35 shall be used for measuring the pressure in the lubricant supply conduit 9 - the common rail for supplying lubricant to the injectors 4.
  • FIG. 2 a pressure gauge 35 for each injector is illustrated, however in some practical embodiments of the system fewer pressure gauges may be provided. In some embodiment only one pressure gauge is used for the lubricant supply conduit 9.
  • the signal from the pressure gauge for the actual pressure in the lubricant supply conduit 9 is then transmitted to the controller and used in calculation of a desired pressure depending on the load condition of the engine which pressure is obtained by controlling a high-pressure pump in the lubricant supply.
  • the high-pressure pump may not be adjustable and in this situation the desired pressure in the lubricant supply conduit 9 is obtained by controlling valves provided in connection with high-pressure pump and used for connecting the high-pressure pump to the lubricant supply conduit 9.
  • FIG. 5 illustrates one half of a cylinder 1 of a large slow-running two-stroke engine, for example marine diesel engine.
  • the cylinder 1 comprises a cylinder liner 2 on the inner side of the cylinder wall 3.
  • the injectors 4 are distributed along a circle with the same angular distance between adjacent injectors 4, although this is not strictly necessary. Also, the arrangement along a circle is not necessary, seeing that an arrangement with axially shifted injectors is also possible, for example every second injector shifted towards the piston’s top dead centre (TDC) relatively to a neighbouring injector.
  • TDC top dead centre
  • Each of the injectors 4 has a nozzle 5 with a nozzle aperture 5’ from which a fine atomized spray 8 is ejected under high pressure into the cylinder 1.
  • the nozzle aperture 5’ has a diameter of between 0.1 and 0.8 mm, such as between 0.2 and 0.5 mm, which at a pressure of 10-100 bar, for example 25 to 100 bar, optionally 30 to 80 bar or even 50 to 80 bar, atomizes the lubricant into a fine spray 8, which is in contrast to a compact jet of lubricant.
  • the swirl 14 of the scavenging air in the cylinder 1 transports and presses the spray 8 against the cylinder liner 2 such that an even distribution of lubrication oil on the cylinder liner 2 is achieved.
  • This lubrication system is known in the field as Swirl Injection Principle, SIP.
  • the cylinder liner 2 is provided with free outs 6 for providing adequate space for the spray 8 or jet from the injector 4.
  • the injectors 4 receive lubrication oil through a lubricant supply conduit 9 - being a common supply conduit, from a lubricant supply 25, including a lubricant pump that raises the pressure of the lubricant to an adequate level.
  • the pressure in the supply conduit 9 is in the range of 10 bar to 400 bar, preferably a range of 25 to 100 bar, optionally 30 to 80 bar, which is a typical range of pressure for spray injectors, e.g. SIP injectors.
  • the injectors 4 are provided with electrical connectors 110’ that are electrically communicating with a controller 11 through electrical cables 110. As mentioned earlier the injectors may alternatively be wireless communicating with the controller 11.
  • the controller 11 sends electrical control signals to the injectors 4 for controlling injection of lubricant by the injector 4 through the nozzle 5.
  • one cable 110 is provided for each injector 4, which allows individual control of injection by the respective injector.
  • one electrical cable 110 from the controller 11 to a subgroup of injectors, for example a subgroup of 2, 3, 4, 5 or 6 injectors, such that a first subgroup is controlled by the controller through a first cable 10 and a second subgroup is controlled through a second cable 110.
  • the number of cables and subgroups are selective dependent on preferred configurations.
  • the engine differs as it comprises a pressure gauge 35.
  • the pressure gauge may also be called a pressure sensor.
  • the pressure gauge 35 shall be used for measuring the pressure in the lubricant supply conduit 9 - the common rail for supplying lubricant to the injectors 4.
  • FIG. 5 a pressure gauge 35 for each injector is illustrated, however in some practical embodiments of the system fewer pressure gauges may be provided. In some embodiment only one pressure gauge is used for the lubricant supply conduit 9.
  • the signal from the pressure gauge for the actual pressure in the lubricant supply conduit 9 is then transmitted to the controller and used in calculation of a desired pressure depending on the load condition of the engine which pressure is obtained by controlling a high-pressure pump in the lubricant supply.
  • the electrical control signals from the controller 11 to the injectors 4 are provided in precisely timed pulses, synchronised with the piston motion in the cylinder 1 of the engine.
  • the controller system 11 comprises a computer 11’ or is electronically connected a computer 11’, by wires or wireless, where the computer 11 ’ monitors parameters for the actual state and motion of the engine, for example speed, load, and position of the crankshaft, where the latter reveals the position of the pistons in the cylinders.
  • Fig. 6 illustrates principal sketches of an injector 4.
  • Fig. 6 is an overview sketch with three different views of the exemplified injector, top view, end view and cross-sectional side view.
  • the injector 4 comprises a lubricant inlet port 112 for receiving lubricant from the lubricant supply conduit 9.
  • the inlet port 112 is provided in an inlet-valve housing 121 comprising an inlet-valve system 113 communicating with the inlet port 112 for regulating the amount of lubricant received from the lubricant supply conduit 9 during a lubrication phase.
  • the injector 4 also comprising an outlet-valve system 115 for regulating the lubricant that is dispensed through the nozzle aperture 5’ .
  • a rigid flow chamber 116 connects the inlet-valve system 113 with the outlet-valve system 115 for flow of lubricant to the nozzle 5.
  • the flow chamber 116 is provided as a hollow rigid rod.
  • the flow chamber 116 is sealed against the inlet-valve housing 121 of the inlet-valve system 113 by an O-ring 122 and held tightly against the inletvalve housing 121 by a flange 123 that is bolted by bolts 124 against the inlet-valve housing 121.
  • Fig. 7 is an enlarged portion of the inlet-valve system.
  • Fig. 7 illustrates the inlet-valve system 113 in greater detail.
  • a non-return inlet-valve 125 is provided with an inlet-valve member 126 that is pre-stressed against an inlet-valve seat 127 by an inlet-valve spring 128.
  • the inletvalve member 126 is exemplified as a ball, however, a different shape, for example oval, conical, plane, or cylindrical, would also work.
  • a push-member 131 In order to displace the inlet-valve member 126 (ball), a push-member 131, exemplified as a push-rod, is provided reciprocal in the channel 129.
  • the push-member 131 is not fastened to the inlet-valve member 126 but is fastened to a reciprocal solenoid-plunger 133 that is driven by a solenoid coil 132.
  • the solenoid-plunger 133 is retracted by a plunger spring 134 when in idle condition.
  • the solenoid-plunger 133 When the solenoid coil 132 is excited by electrical current, the solenoid-plunger 133 is moved forward against the force of the plunger spring 134 until it comes to a halt against a plunger stop 135. Due to the movement of the solenoid-plunger 133, the push-member (push-rod) 131 pushes the inletvalve member (ball) 126 away from the inlet-valve seat 127, allowing lubricant to flow through the inlet non-return valve 125 and into the flow chamber 116.
  • the push-member (push-rod) 131 is withdrawn a distance from the inlet-valve member (ball) 126 when in idle state, such that there is a free range distance in between the push-member 131 and the inlet-valve member 126.
  • the solenoid coil 132 When the solenoid coil 132 is excited, the push-member 131 is accelerated by the solenoid coil 132 over the free-range distance before it impacts the inlet-valve member 126 after initial acceleration. This results in the inlet-valve member 126 being displaced abruptly from the inlet-valve seat 127, as compared to a situation where the inlet-valve member 126 moves together with push-member 131 during the first part of the acceleration.
  • the quick displacement of the inlet-valve member 126 is advantageous for a precise timing of the start of the lubricant injection into the cylinder 1.
  • the free- range distance is adjustable by an adjustment screw 136 at the end of the solenoidplunger 133.
  • the lubricant supply from the inlet port 112 to the nozzle 5 is stopped by cutting the current to the solenoid coil 132, which results in the solenoidplunger 133 being pushed back by the plunger spring 134, and the inlet-valve member 126 returns to the tight inlet-valve seat 127 for an idle phase in the injection cycle.
  • Fig. 8 corresponds to Fig. 1 and illustrates a further embodiment of one half of a cylinder 1 of a large slow-running two-stroke engine, for example marine diesel engine.
  • This embodiment comprises oil injectors.
  • the injectors 4 may be HJ Smartlube 4.0 E-injec- tors.
  • the injectors 4 are connected with a cylinder-manifold with flowmeter 203.
  • the cylinder-manifold with flowmeter is connected with a controller 11 via a communication line 211 for flowmeter feedback signals.
  • the controller 11 may be a local cylinder controller which is connected with a central controller 208 via a communication line 210.
  • the cylinder-manifold with flowmeter 203 is connected with a pump unit 205.
  • the pump unit 205 is via the supply conduit 12 connected with the lubricant supply 25.
  • the pump unit 205 is via a pressurized oil feed line 214 connected to cylinder manifolds (common rail) for providing lubricant oil to the injectors 4.
  • An injector signal bus 212 connects the controller 11 with the injector for regulating the lubricant amount and to effect calibration of the injectors.
  • Fig. 15 shows a partially sketch of a common rail system comprising a common rail, a high-pressure unit with a pump and a valve.
  • the valve may be omitted in case the pump is variable.
  • the pump may be variable for regulating the rotation speed of the pump and thereby the output of high-pressure pump for obtaining the desired pressure in the lubricant supply conduit.
  • the pump is not variable. Instead, the valve arranged at the high-pressure pump and connecting the high- pressure pump with the lubricant supply conduit is used. In this situation the regulation of the valve is used for regulating the pressure in the lubricant supply conduit to the desired pressure.
  • the valve is connected to the pressure side and suction side of the high-pressure pump.
  • the valve may relieve the pressure as it is connection to the suction side of the high-pressure pump or to a return line to the lubricant supply.
  • the injector is preferably of a type generally described in WO 2012/126473. This injector is also known as Hans Jensen Lubricators E-sip injector.
  • the injector can be actuated electromechanically, for example in the form of a solenoid valve or piezo-mechanical element.
  • Fig. 16 and Fig. 17 show a further embodiment of an injector to be used in a system according to the present invention and illustrated in closed position and in open position respectively.
  • the injector illustrated in Figs. 16 and 17 is actuated electromechanically in the form of a solenoid valve.
  • the injector is made as a unit, that the opening/closing valve is an electromechanical valve integrated in the injector for dosing the lubricating oil.
  • the electromechanical opening/closing valve includes a spring-biased valve stem.
  • Dosing of lubricating oil is performed by activating the opening/closing valve in in the injector for dosing the lubricating oil.
  • the activation moves the valve stem of the opening/closing valve and the injection of the lubricating oil.
  • plunger-valve spring pre-stressing plunger-valve ball 26A against plunger-valve seat 26B 27 pressure chamber at rear part 28B
  • inlet non-return valve exemplified as inlet ball valve

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Lubrication Of Internal Combustion Engines (AREA)

Abstract

L'invention concerne un moteur de grande taille, en particulier un moteur marin ou un moteur pour centrales électriques, et un procédé de lubrification du moteur avec des injecteurs de pulvérisation, en particulier des injecteurs SIP. Selon le procédé, il est prévu un dispositif de commande conçu pour faire varier et commander la pression dans le conduit d'alimentation en lubrifiant à l'intérieur d'une plage de pression souhaitée et baser la pression souhaitée sur la charge de moteur et une mesure de la pression réelle dans le conduit d'alimentation en lubrifiant.
PCT/DK2024/050040 2023-06-11 2024-03-04 Procédé de lubrification d'un grand moteur à deux temps à l'aide de variations de pression contrôlées dans un rail commun Pending WO2024255975A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
KR1020267000197A KR20260022377A (ko) 2023-06-11 2024-03-04 공통 레일에서 제어된 압력 변화를 이용하는 대형 2행정 엔진 윤활 방법
CN202480037297.0A CN121263591A (zh) 2023-06-11 2024-03-04 一种利用共轨中受控压力变化来润滑大型二冲程发动机的方法

Applications Claiming Priority (2)

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DKPA202370282A DK181696B1 (en) 2023-06-11 2023-06-11 A method for lubricating a large two-stroke engine using controlled pressure variations in common rail
DKPA202370282 2023-06-11

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WO2024255975A1 true WO2024255975A1 (fr) 2024-12-19

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KR (1) KR20260022377A (fr)
CN (1) CN121263591A (fr)
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2025131193A1 (fr) * 2023-12-20 2025-06-26 Hans Jensen Lubricators A/S Procédé de lubrification de gros moteurs à deux temps par cavitation asymétrique dans la buse d'injecteur

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0049603A2 (fr) * 1980-10-04 1982-04-14 The British Petroleum Company p.l.c. Système de lubrification
DE10220015A1 (de) * 2001-05-07 2002-11-21 Man B & W Diesel As Kopenhagen Verfahren zum Einspritzen von Schmieröl in einen Zylinder eines Verbrennungsmotors
JP2004239157A (ja) * 2003-02-06 2004-08-26 Hitachi Zosen Corp ディーゼルエンジンにおける注油装置
US20080314686A1 (en) * 2007-06-20 2008-12-25 Crr Developments Pty Ltd System and method for engine lubrication
WO2013136961A1 (fr) * 2012-03-16 2013-09-19 三菱重工業株式会社 Dispositif de graissage de cylindre
EP3368751A1 (fr) * 2015-10-28 2018-09-05 Hans Jensen Lubricators A/S Grand moteur deux temps à bas régime avec injecteur de lubrifiant à sip
WO2018215645A1 (fr) * 2017-05-26 2018-11-29 Hans Jensen Lubricators A/S Procédé de lubrification de gros moteurs à deux temps par cavitation contrôlée dans la buse d'injecteur
WO2023088526A1 (fr) * 2021-11-17 2023-05-25 Hans Jensen Lubricators A/S Moteur de grande dimension à deux temps à déplacement lent, procédé de lubrification de ce dernier et utilisation du moteur et du procédé

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0049603A2 (fr) * 1980-10-04 1982-04-14 The British Petroleum Company p.l.c. Système de lubrification
DE10220015A1 (de) * 2001-05-07 2002-11-21 Man B & W Diesel As Kopenhagen Verfahren zum Einspritzen von Schmieröl in einen Zylinder eines Verbrennungsmotors
JP2004239157A (ja) * 2003-02-06 2004-08-26 Hitachi Zosen Corp ディーゼルエンジンにおける注油装置
US20080314686A1 (en) * 2007-06-20 2008-12-25 Crr Developments Pty Ltd System and method for engine lubrication
WO2013136961A1 (fr) * 2012-03-16 2013-09-19 三菱重工業株式会社 Dispositif de graissage de cylindre
EP3368751A1 (fr) * 2015-10-28 2018-09-05 Hans Jensen Lubricators A/S Grand moteur deux temps à bas régime avec injecteur de lubrifiant à sip
WO2018215645A1 (fr) * 2017-05-26 2018-11-29 Hans Jensen Lubricators A/S Procédé de lubrification de gros moteurs à deux temps par cavitation contrôlée dans la buse d'injecteur
WO2023088526A1 (fr) * 2021-11-17 2023-05-25 Hans Jensen Lubricators A/S Moteur de grande dimension à deux temps à déplacement lent, procédé de lubrification de ce dernier et utilisation du moteur et du procédé

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2025131193A1 (fr) * 2023-12-20 2025-06-26 Hans Jensen Lubricators A/S Procédé de lubrification de gros moteurs à deux temps par cavitation asymétrique dans la buse d'injecteur

Also Published As

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CN121263591A (zh) 2026-01-02
DK202370282A1 (en) 2024-09-27
KR20260022377A (ko) 2026-02-19
DK181696B1 (en) 2024-09-27

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