Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D13/00—Pumping installations or systems
  • F04D13/02—Units comprising pumps and their driving means
  • F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/06—Lubrication
  • F04D29/061—Lubrication especially adapted for liquid pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/08—Sealings
  • F04D29/10—Shaft sealings
  • F04D29/106—Shaft sealings especially adapted for liquid pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D7/00—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts
  • F04D7/02—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts of centrifugal type
  • F04D7/08—Pumps adapted for handling specific fluids, e.g. by selection of specific materials for pumps or pump parts of centrifugal type the fluids being radioactive
• • G—PHYSICS
  • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
  • G21C—NUCLEAR REACTORS
  • G21C15/00—Cooling arrangements within the pressure vessel containing the core; Selection of specific coolants
  • G21C15/24—Promoting flow of the coolant
  • G21C15/243—Promoting flow of the coolant for liquids

Definitions

• TITLE Rotating machine, primary motor-pump unit equipped with this rotating machine
• the invention relates to a rotating machine, as well as a motor-pump unit equipped with this rotating machine.
• the field of the invention generally relates to rotating machines requiring to be lubricated by oil. This is the case, for example, of water circulation pump motors installed in the primary circuit of a nuclear power plant; these circulation pumps and their respective motors will be referred to below as the primary pump motor unit.
• the fields of application can be extended to turbines, pumps, motors, alternators, and any gear or machine comprising a rotating shaft.
• a rotating machine 10 known in the state of the art comprises a casing 32, a rotary shaft 33 on bearings 22, 23, 24 for guiding, the casing 32 containing a volume 310 of lubricating oil to lubricate the bearings 22, 23, 24.
• the rotating machine 10 comprises a rotating part 360, integral in rotation with the rotating shaft 33.
• the rotating machine 10 comprises a device 35 for sealing oil, located between a rotating part 360 secured to the shaft 33 and an upper part 320 of the housing 32.
• sealing devices 35 are known, formed by a system 35 of baffles and labyrinth, located between the rotating part 360 and the upper part 320 of the housing 32, as shown in Figures 1 and 2.
• This device 35 is called in everyday language “sealing device” because it offers a function of limiting the leakage of the lubricant from the housing 32 to the outside of the latter.
• This limitation of leaks does not lead to total sealing, however it is a function of several parameters including, for example, and not limited to: the length of the baffles: the longer they are, the more the limitation of leaks is improved, the number of teeth arranged between the baffle and the rotating part: the more there are, the more the limitation of leaks is improved, the distance between the rotating part 360 and the end of the labyrinth teeth: the smaller it is, the more the limitation of leaks is improved, the pressure and speed fluctuations originating from the rotating members, the rotating shaft 33 of which -even, combined with the presence of a flywheel 36 in the case of a primary motor-pump unit: the weaker they are, the more the limitation of leaks is improved.
• a filtration device 100 oil-laden air coupled to a fan motor 101.
• Said filtration device 100 is intended to ensure the separation of the oil contained in the air, this oil is reinjected into the casing 32.
• Said fan motor 101 ensures a depression of the casing 32 with respect to the external pressure of the machine generating a flow of air coming from the outside of the machine and crossing the sealing device 35 which has the effect of limiting the ascents of oil mist 39 coming from the casing 32 through the sealing device 35.
• This known rotating machine 10 has the drawback of requiring a motorized fan/extractor 101 which must be supplied with electricity in order to operate (or even be driven mechanically).
• This type of motorized fan/extractor 101 has on the one hand a high cost of installation, particularly in a nuclear power station and this because of the numerous components to be installed such as the cells of the electrical outlets, the cables and the control-command.
• such an installation generates additional maintenance costs including periodic maintenance of the fan motor / extractor 101 (replacement of bearings, mechanical inspection). And finally, such an installation generates high operating costs due to the high electrical consumption of the fan motor.
• the aim of the invention is to obtain a rotating machine and a primary motor-pump unit equipped with this rotating machine, which solves the problem mentioned above and makes it possible to limit in a robust manner, or even to eliminate oil leaks through the sealing device between the shaft and the housing.
• a first object of the invention is a rotating machine, comprising a casing, at least one shaft rotating in a prescribed direction of rotation, at least one guide bearing, which is mounted in the casing and in which the rotary shaft is rotatably mounted, the casing delimiting a compartment intended to contain a volume of air and a volume of lubricating oil to lubricate the bearing, the rotary machine comprising a rotating part, integral in rotation with the rotary shaft and surrounded by an upper part of the casing transversely to the rotary shaft and at a distance from the bearing, an oil sealing device, located between the rotating part and the upper part of the casing, and a compartment air filtration device and for rejecting air to the outside of the compartment, characterized in that the oil sealing device comprises at least one groove for sucking in outside air in the direction of rotation of the shaft, the groove being located d in the rotating part and/or in the upper part of the casing, the rotating part being without contact with the upper part of the casing, the grooving
• the rotation of the shaft in the prescribed direction creates in the grooving a counter-current of air, which comes from the outside, passes from the upstream end to the downstream end in the device of seal between the crankcase and the rotating part towards the crankcase oil compartment, and penetrates from the downstream end into the crankcase oil compartment against the oil mist, having been generated in the crankcase by the rotation of the shaft.
• This causes the oil mist generated in the crankcase by the rotation of the shaft to be confined within the oil compartment of the crankcase.
• the air extractor fan motor is advantageously.
• the invention makes it possible to incorporate an autonomous device capable of setting in motion and diverting the air flows from the outside to the inside at the level of the sealing device.
• a contact seal radial or axial, for example a lip seal
• a mechanical seal which has the advantage of having a low level leak rate.
• the invention makes it possible to solve the problem mentioned below with a sufficient lifetime of the sealing device for a high peripheral speed of the shaft at the level of this sealing device, particularly in motor pump units. reactors of nuclear power plants.
• the rotary shaft is vertical
• the upstream air suction end is an upper air suction end
• the downstream air ejection end is a lower end of air ejection.
• the external air intake groove is inclined at a determined non-zero angle of inclination with respect to a plane transverse to the shaft and extends around a direction extension of the shaft, around which the shaft is able to rotate in the prescribed direction of rotation.
• the determined non-zero angle of inclination with respect to the transverse plane is greater than 0° and less than or equal to 60°.
• the determined non-zero angle of inclination with respect to the transverse plane is greater than or equal to 1° and less than or equal to 45°.
• the depth of the grooving in a plane transverse to the shaft is greater than 0 mm and less than or equal to 30 mm.
• the length of the groove along a direction of extension of the shaft, around which the shaft is capable of rotating in the prescribed direction of rotation is greater than 0 mm and less than or equal to 200 mm.
• the grooving comprises a number of grooves greater than or equal to 1 and less than or equal to 150 along a direction of extension of the shaft, around which the shaft is capable to rotate in the prescribed direction of rotation.
• the radial play between the outer diameter of the rotating part and the inner diameter of the upper part is greater than 0 mm and less than or equal to 6 mm.
• the external air intake groove is in the form of screwing from the upstream air intake end to the downstream air ejection end in the prescribed direction. rotation.
• the outside air intake groove is helical.
• the device for filtering air from the compartment and for rejecting air out of the compartment comprises an air inlet connected to an air outlet from the compartment, an outlet of filtered oil, connected to an oil inlet of the compartment, and a filtered air ejection outlet, vented to the outside of the compartment.
• the air filtration device of the compartment comprises an air inlet connected to an air outlet of the compartment, a filtered oil outlet, connected to an oil inlet of the compartment, and a filtered air ejection outlet, connected to an air suction inlet of a fan motor for extracting air to the outside of the compartment.
• the filtered oil outlet is connected to the oil inlet of the compartment via at least one oil pipe comprising at least one gooseneck oriented towards the down.
• a second object of the invention is a primary motor-pump unit, intended to be mounted in at least one primary pressurized water circuit of a nuclear power plant for the production of electricity, the primary motor-pump unit comprising a primary pump with a water pumping wheel and a rotating machine as described above, the rotating shaft of which is fixed to the pumping wheel of the primary pump for its rotational drive.
• a third object of the invention is a primary motor-pump unit as described above, characterized in that the primary motor-pump unit comprises a flywheel fixed to the rotating shaft, the rotating part is a wall ring integral with the flywheel and extending around the rotary shaft.
• Figure 1 shows a schematic view in vertical section of a known rotating machine.
• Figure 2 shows an enlarged schematic view in vertical section of the known rotating machine of Figure 1.
• Figure 3 shows a schematic perspective view of a primary circuit of a nuclear power plant in which the rotating machine is mounted according to one embodiment of the invention.
• FIG. 4 represents a schematic view in open perspective of a primary motor-pump unit of the primary circuit of FIG. 3, comprising the rotating machine according to one embodiment of the invention.
• FIG. 5 represents a schematic view in vertical section of part of the rotary machine of FIG. 4 according to the state of the art.
• FIG. 6 represents a schematic view in vertical section of part of the rotating machine according to one embodiment of the invention.
• FIG. 7 represents a schematic view in vertical section of part of the rotating machine according to another embodiment of the invention.
• FIG. 8 represents a schematic view in vertical section of part of the rotating machine according to another embodiment of the invention.
• Figure 9 shows a schematic view in enlarged vertical section of part of the rotating machine according to the embodiment of the invention of figure 6.
• Figure 10 shows a schematic view in enlarged vertical section of part of the rotating machine according to the embodiment of the invention of Figure 6.
• FIG. 11 represents a schematic view in vertical section of part of the rotating machine according to another embodiment of the invention.
• Figure 12 shows a schematic view in vertical section of part of the rotating machine of Figure 4 according to an embodiment of the invention.
• FIG. 13 represents a schematic view in vertical section of part of an air filtration device of the rotating machine according to one embodiment of the invention.
• the rotating machine 10 comprises a casing 32, at least one rotary shaft 33 in a prescribed direction S of rotation, at least one bearing 22, 23, 24 for guiding , which is mounted in the housing 32 and in which the rotary shaft 33 is rotatably mounted.
• the rotating machine 10 can function as a motor.
• the rotating machine 10 can operate as a generator.
• the casing 32 delimits a compartment 31 intended to contain a volume
• the rotating machine 10 comprises a rotating part 360, integral in rotation with the rotating shaft 33.
• the rotating part 360 surrounds the rotary shaft 33 and can be annular around the direction D of extension of the shaft 33 and for example circular cylindrical around this direction D.
• the rotating machine 10 comprises a crossing 50 of the shaft 33 in the casing 32. In this crossing 50, the rotating part 360 faces and is surrounded by an upper part 320 of the casing 32 transversely to the rotary shaft 33 and at a distance from the bearing 22, 23, 24.
• the upper part 320 of the casing 32 can be annular around the direction D of extension of the shaft 33 and can be circular cylindrical around this direction D.
• the rotating machine 10 comprises an oil sealing device 35, located between the rotating part 360 and the upper part 320 of the casing 32 , and a device 100 for filtering the air from the compartment 31, which is intended to separate the air from the oil.
• the oil seal 35 is located remote from the bearing 22, 23, 24.
• the shaft 33 passes through the housing 32 and the oil seal 35.
• the air filtration device 100 is configured to reinject oil, having been trapped in this filtration device 100, into the volume 310 of oil.
• an example of the use of the rotating machine 10 according to the invention is a primary motor-pump unit 2, mounted in the primary circuit 20 of a nuclear power plant for the production of electricity.
• the primary motor-pump unit 2 comprises a primary pump 28 with impeller 280 for pumping water and the rotating machine 10 according to the invention, operating as a motor.
• Rotating shaft 33 is attached to pump impeller 280 of primary pump 28 so that rotation of shaft 33 causes rotation of pump impeller 280.
• the rotating machine 10 according to the invention could be used elsewhere than in a primary motor-pump unit 2.
• Other examples of use are the sealing of turbine bearings, alternators, pumps, motors .
• the primary water circulation circuit 20 of the nuclear power plant for example a pressurized water reactor, comprises one or more primary water circulation loops 11a, 11b, 11c, which are connected to a water tank 1.
• each primary water circulation loop 11a, 11b, 11c there is a primary motor-pump unit 2, a steam generator 3 to send water successively from the tank 1 to the steam generator 3 (according to the water circulation direction S1), then from the steam generator 3 to an upstream water inlet pipe 29 of the primary motor-pump unit 2 (in the water circulation direction S2), and finally from a downstream pipe 30 for the water outlet of the primary motor-pump unit 2 (in the direction S3 of water circulation) to the tank 1.
• One of the primary loops 11a, 11b, 11c for example the primary loop 11a , includes a water pressurizer 4 intended to control the pressure in the entire primary circuit 20.
• FIG. 4 An example of a primary motor pump unit 2 comprising the rotating machine 10 operating as a motor is shown in more detail in FIG. 4 and comprises, from top to bottom:
• a primary pump 28 consisting of its volute, its pumping wheel 280, its diffuser, and its sealing device and its pivoting members.
• the lower bearing 26 has its own oil sump (different from the upper bearing 22,23,24) and its own oil and is therefore not affected by the leakage problems according to the invention (separate from that of the upper bearing) .
• an oil mist 39 is generated due to the rotation of the shaft 33 and the operation of the bearings 22, 23, 24, in particular the upper guide bearing 22, so and so although the air 34 located above the level 313 of oil 310 in the compartment 31 is loaded with a fine mist 39 of oil and oil vapour. More than 95% of the oil droplets in this fog 39 are between 0.15 and 1.0 ⁇ m in size.
• This mist 39 circulates along path B as shown in FIG. 5, said mist 39 spreading in two paths which separate, the first along an internal escape path F1, the second along an external escape path F passing through the seal. 35 and generating an overall external leak M loaded with oil that the present invention proposes to limit or eliminate thanks to the dynamic control of the leak F.
• the present invention aims to limit or even eliminate all of these drawbacks by proposing an installation providing dynamic sealing on rotating machines 10 in operation, by an installation incorporated from the manufacture and implementation of these rotating machines 10. aims to significantly reduce oil leaks M by spray/oil mist emitted into the atmosphere by the rotating machines 10 requiring lubrication of FIGS. 6 to 12, such as for example the motors of water circulation pumps operated in nuclear power plants according to Figures 3 to 5.
• the oil sealing device 35 comprises at least one groove 52 for sucking in outside air in the direction S of rotation of the shaft 33.
• the groove 52 is located in the rotating part 360 secured to the shaft 33.
• the groove 52 is located in the upper part 320 of the casing 32, surrounding the rotating part 360 integral with the shaft 33.
• This groove 52 in the static part 320 is typically well suited for upgrading existing machines, for example primary pump motors, due to the reduction in modifications to be made to the machine and the non-creation of mechanical imbalance.
• the groove 52 is located both in the rotating part 360 fixed to the shaft 33 and in the upper part 320 of the casing 32, surrounding the rotating part 360 integral with shaft 33.
• One or more grooves may be provided in groove 52.
• the rotating part 360 (or rotor) integral with the shaft 33 does not touch the upper part 320 (or stator) of the casing 32, the groove 52 being located between the rotating part 360 secured to the shaft 33 and the upper part 320 of the casing 32.
• the oil sealing device 35 is contactless in the passage 50 of the shaft 33 in the casing 32.
• the groove 52 extends from an upstream end 521 of the air intake of the rotating part 360 and/or of the upper part 320 of the casing 32 to a downstream end 522 for ejecting air from the rotating part 360 and/or from the upper part 320 of the casing 32.
• the upstream end 521 for air suction is located on the side of an opening 37, 370 of air communication of the rotating machine 10 with the exterior 60.
• the downstream end 522 of air ejection is in communication with the compartment 31 of the housing 32.
• the opening 370 of air communication with the exterior 60 is located between the rotating part 360 integral with the shaft 33 and the upper part 320 of the casing 32.
• the groove 52 for sucking in outside air is configured (oriented) to suck in air (arrows AA in FIGS. 6, 7, 8, 9 and 11) from the upstream end 521 to the downstream end 522, that is to say the opening 37, 370 of air communication to the compartment 31, when the shaft 33 rotates in the direction S prescribed rotation.
• the present invention improves the current state of the art represented by FIGS. 1 and 2, in that the installation according to the invention, as illustrated in FIGS. 6 to 12, makes it possible to discharge by air sucked AA the mist 39 of oil in the compartment 31, to move this mist 39 of oil away from the gap located between the rotating part 360 and the upper part 320 of the housing 32 and to push it towards the device 100 air filtration, and is combined with the incorporation of an autonomous device 35 during the rotation of the shaft 33 in the prescribed direction S to set in motion and push the flows 34 of oil-laden air 39 towards the air filtration device 100, thanks to one (or more) part 360 and/or 320 having one (or more) grooves 52 in place of the labyrinth of the prior art of FIGS. 1 and 2.
• the invention makes it possible to recover a greater quantity of oil droplets/vapors 39 and to return condensates of this recovered oil 39 to the zone to be sealed (bearing) or to the oil compartment 31 for reuse.
• the device 100 makes it possible to reprocess a greater quantity of incoming air to rid it of its oil 39 and to evacuate the clean air from the rotating machine 10.
• the invention uses the rotation of the shaft 33 in the direction S prescribed to create the barrier airflow AA.
• the sealing of the device 35 and the speeding up of the sucked air AA are carried out by a single piece 52 which replaces the labyrinths conventionally used on rotating machines 10.
• the sealing device 35 is autonomous : it is not necessary to power the system electrically or mechanically (interesting for isolated machines, significant reduction in installation and maintenance costs, no piping, no electrical outlet).
• the fact that the sealing device 35 is without contact between the stator part 320 and the rotor part 360 is advantageous, because there is therefore no mechanical wear, nor influence on the dynamic behavior of the line.
• venting system 100 makes it possible to guarantee complete sealing of the shaft bushing 50 by ensuring a minimum flow rate of incoming fluid AA. This minimum flow is a function of several parameters (play J between rotor and stator, speed of rotation, diameter to be sealed, etc.). According to one embodiment of the invention, for the primary pump motors 28, it is of the order of one hundred liters/minute.
• the invention makes it possible to solve the problems of oil leaks by spray from the bearings 22, 23, 24 of the primary pump motors 28 forming rotating machines 10.
• the undesirable presence of oil was detected on the primary pump motors (cover vents 38 of flywheel 36, drip trays oil, air coolers, primary pump motor support, etc.) and their environments (reactor building wall, heat insulation, grating, etc.).
• the need to be satisfied is non-pollution of the environment of the primary pump motor, in order to reduce maintenance and operating costs (cleaning, replacement of soiled components, waste management, dosimetry, these costs generated by leaks possibly be around 20 k € / year / unit and up to 80 k € if the main primary circuit insulation was polluted), in order to reduce the risk of chance linked to the migration of oil on sensitive components (sensors ,...), and in order to secure the installations: reduction of the risk of falling on the same level, reduction of the duration of human interventions in connection with these leaks.
• the improvement provided by the invention makes it possible to guarantee the confinement of the oil inside the casing 32 and the bearings of the engine by taking into account the following constraints (non-exhaustive) without adding any significant maintenance operation, nor modify the operating behavior of the machine: primary pump motor with vertical shaft, diameter of the shaft at the level of the bearing of approximately 440 mm, nominal speed of rotation of the shaft of 1485 revolutions/minute, fluid to be sealed: grade 46 mineral oil in the form of projection or steam at a temperature between 10 and 80° C, number of hours of operation of a primary pump motor of approximately 8,000 hours/year (continuous operation), duration between two general engine maintenance operations of more than 25 years, engine ambient condition (ambient of the reactor building): pressure of 1 ⁇ 0.2 bar absolute, relative humidity of 50%, radiation level of 0.5 Gy/h, normal ambient temperature between 10 and 45°C.
• the rotary shaft 33 is vertical and is capable of rotating in the prescribed direction S of rotation around the direction D of extension of the shaft 33, which is the vertical direction Z.
• the upstream end 521 of air suction is an upper end 521 of air suction.
• the downstream end 522 of air ejection is a lower end 522 of air ejection.
• the groove 52 for sucking in outside air is continuous from the upstream end 521 of air intake to the downstream end 522 of ejection. of air.
• the grooving 52 for sucking in outside air is inclined at a determined angle a that is non-zero with respect to a plane PT transverse (normal) to the shaft 33 and in the direction D and extends around the direction D of extension of the shaft 33, around which the shaft 33 is capable of rotating in the prescribed direction S of rotation.
• the plane PT is horizontal.
• the determined angle a with respect to the transverse plane PT is between 0 and 60°, in particular between 1° and 45°, for example between 1° and 25°.
• the number of grooves of the grooving 52 connecting one after the other along the direction D, their depth P in the transverse plane PT, their shape, their angle a with the normal to the direction D of extension, the length L of the sealing device 35 along the direction D of extension and the radial clearance J (in the direction of the transverse plane PT, starting from the direction D) between the outer diameter of the rotating part 360 and the inside diameter of the upper part 320 is a function of the geometry of the zone 50 to be sealed and of the functional parameters of the machine (vibration level, play in the bearings, etc.).
• the number of grooves is between 1 and 150
• the depth P of the grooves 52 is between 0 and 30 mm
• the angle a of the grooves with the normal in the direction D of extension is between 0 and 60°
• the length L of the sealing device along the direction D of extension is between 0 and 200 mm
• the radial clearance J between the outer diameter of the rotating part 360 and the inside diameter of the upper part 320 is between 0 and 6 mm.
• the grooving 52 for suction of outside air is in the form of screwing from the upstream end 521 of air suction to the downstream end 522 ejection of air in the prescribed direction of rotation S.
• This may be a particular implementation of the determined angle a, of the number of grooves (each groove in this case being a thread making a turn around the direction D and the grooves being connected to each other along the direction D), depth P, length L and clearance J.
• the groove 52 for sucking in outside air is helical. This may be a particular implementation of the determined angle a, of the number of grooves (each groove in this case being a thread making a turn around the direction D and the grooves being connected to each other along the direction D), depth P, length L and clearance J.
• the device 100 for filtering air from compartment 31 and rejecting air to the outside 60 from compartment 31 comprises an air inlet 112 connecting an air outlet 312 of compartment 31 to a filter 104, for example coalescent.
• the filter 104 filters the oil-laden air 34 arriving in the air inlet 112 to separate the oil 39 and the air and send the oil 39 thus recovered to its outlet 110 of filtered oil, then to the compartment 31 by an oil pipe 114 connecting the oil inlet 311 of the compartment 31 to this outlet 110 of filtered oil.
• the filter 104 sends the filtered air 120 to its filtered air ejection outlet 102, which is vented to the outside 60 of the compartment 31.
• the air filtration device 100 thus makes it possible to vent the oil compartment 31 310, to filter the air 34 contained in the oil compartment 31 310, to separate the air 34 from its oil droplets/vapors 39, to restore to the outside 60 of the housing 32 the air 120 stripped of its oil 39, and return the oil condensates 39 extracted from the air 34 to the volume 310 of liquid oil of the compartment 31 via the outlet 110 and the inlet 311.
• the air 34 laden with oil 39 and particles coming from the oil compartment 310 passes through the filter media 150 of the filter(s) 104.
• the oil droplets and vapor 39 are separated from the air through the filter media 150. A once separated, the oil droplets 39 agglomerate into larger oil drops and descend by gravity along the arrow G in the filter 104.
• the return of these oil condensates 39 to the compartment 31 of oil 310 by the oil return system 110, 311 is characterized in that it prevents air 34 laden with particles located in the casing 32 to be sealed from bypassing the filter or filters 104 of the filtration system 100 .
• the oil inlet 311 is located above the oil level 313 of the volume 310 of liquid oil in the compartment 31; thus the return of the oil condensates 39 via this inlet 311 takes place above this oil level 313, in order to reduce the possible leak points.
• the air 120 leaving the filtering element(s) 150 is cleaned of its oil 39 and is evacuated into the environment 60 of the rotating machine 10.
• the number of filters 104 fitted to the venting device 100 depends on several parameters, including in particular the performance of the sealing device 35, the level of particle and oil pollution 39 of the air 34 located in the compartment 31, the expected maintenance intervals, the characteristics of the filters 104 (pressure drop , oil separation efficiency, etc.).
• the device 100 for filtering the air from the compartment 31 and rejecting the air to the outside 60 of the compartment 31 comprises an air inlet 112 connecting to an air outlet 312 of the compartment 31 to a filter 104, for example coalescent.
• the filter 104 filters the oil-laden air arriving in the air inlet 113 to separate the oil and the air and to send the oil thus recovered to its outlet 110 of filtered oil, then to the compartment 31 by an oil pipe 114 connecting the oil inlet 311 of the compartment 31 to this outlet 110 of filtered oil.
• the filter 104 sends the filtered air to a motorized air extraction fan 101, the first filtered air ejection outlet 102 of the filter 104 being connected to an air intake 103 of the motorized air extraction fan 101, a second air ejection outlet 105 of which is vented to the outside 60 of the compartment 31.
• this embodiment can be combined with the different modes of realization of the grooving 52.
• the present innovation improves the most efficient state of the art at the present time, because the dynamic sealing system of the invention is , at equivalent pressure drop, more efficient in terms of oil leakage rate than the conventionally used labyrinth device.
• This can therefore make it possible to reduce the power of the motor-fan unit 101 and therefore to reduce the installation and operating costs, or to improve the rate of oil leakage from the shaft 33 for an iso-power design. of the fan motor 101.
• the sealing device 35 makes it possible to set in motion and create an air flow with sufficient pressure and flow characteristics, the implementation of the fan motor 101 will be useless, or even not necessary in the installation.
• This type of configuration could therefore be found, for example, for demanding conditions (very low level of pollution at the shaft outlet), or specific cases (for example, reducing installation and operating costs (with, for example, the reduction power or even the absence of the fan motor 101)).
• the sealing device 35 according to the invention could be installed wherever the peripheral speeds of shafts 33 are high and where oil leaks are detrimental.
• the filtered oil outlet 110 is connected to the oil inlet 311 of the oil compartment 31 310 via at least one pipe. 114 of oil comprising at least one gooseneck 1120 (or siphon 1120) facing downwards.
• the gooseneck 1120 or siphon 1120 has a lower part 1121 (or bottom 1121) filled with oil in the pipe 114, which prevents air from being sent to the inlet 311 of the compartment 31.
• This neck 1120 swan may for example be U-shaped, or otherwise.
• the gooseneck 1120 or siphon 1120 guarantees blockage of the air 34 contained in the oil compartment 31 thanks to the presence of oil in the bottom 1121 of the gooseneck 1120 or siphon 1120.
• the rotating part 360 is an annular wall secured to the flywheel 36 of inertia and extending around the rotary shaft 33.
• the flywheel 36 of inertia protrudes transversely to the direction D of extension of the shaft 33.
• the rotating part 360 can be formed by an annular part which can take the form of a crown fixed under the flywheel 36 of inertia.
• the upper part 320 of the casing 32 is located at a distance under the flywheel 36 of inertia.
• the sealing device 35 according to the invention is located at a distance under the flywheel 36 of inertia.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Plasma & Fusion (AREA)
• High Energy & Nuclear Physics (AREA)
• Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)
• Rotary Pumps (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=77411796

Family Applications (1)

Country Status (5)

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• 2021
  • 2021-05-27 FR FR2105496A patent/FR3123393B1/fr active Active
• 2022
  • 2022-05-11 WO PCT/EP2022/062725 patent/WO2022248220A1/fr not_active Ceased
  • 2022-05-11 CN CN202280052141.0A patent/CN117716132A/zh active Pending
  • 2022-05-11 US US18/563,220 patent/US12215706B2/en active Active
  • 2022-05-11 EP EP22728572.3A patent/EP4348052A1/de active Pending

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