WO2013167094A2 - Plate-forme robotique pour inspection interne de canalisations - Google Patents

Plate-forme robotique pour inspection interne de canalisations Download PDF

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Publication number
WO2013167094A2
WO2013167094A2 PCT/CO2013/000001 CO2013000001W WO2013167094A2 WO 2013167094 A2 WO2013167094 A2 WO 2013167094A2 CO 2013000001 W CO2013000001 W CO 2013000001W WO 2013167094 A2 WO2013167094 A2 WO 2013167094A2
Authority
WO
WIPO (PCT)
Prior art keywords
pipe
robot
fluid
tubular body
inspection
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CO2013/000001
Other languages
English (en)
Spanish (es)
Other versions
WO2013167094A3 (fr
Inventor
John Faber ARCHILA DÍAZ
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Industrial University of Santander
Original Assignee
Industrial University of Santander
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Industrial University of Santander filed Critical Industrial University of Santander
Publication of WO2013167094A2 publication Critical patent/WO2013167094A2/fr
Publication of WO2013167094A3 publication Critical patent/WO2013167094A3/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/26—Pigs or moles, i.e. devices movable in a pipe or conduit with or without self-contained propulsion means
    • F16L55/28—Constructional aspects
    • F16L55/30—Constructional aspects of the propulsion means, e.g. towed by cables
    • F16L55/38—Constructional aspects of the propulsion means, e.g. towed by cables driven by fluid pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/26—Pigs or moles, i.e. devices movable in a pipe or conduit with or without self-contained propulsion means
    • F16L55/28—Constructional aspects
    • F16L55/40—Constructional aspects of the body
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L2101/00—Uses or applications of pigs or moles
    • F16L2101/30—Inspecting, measuring or testing

Definitions

  • the present invention relates to robotic devices and more particularly, but not exclusively, to robotic devices adapted to travel through pipes or other types of tubular ducts of different diameters, propelled by the flow carried by said ducts. , to perform inspection, cleaning and other maintenance activities.
  • the integrity of pipelines for transporting liquids and gases is of the utmost importance for cities and industries.
  • the standard inspection tool corresponds to the PIG, its acronym in English Pipeline Inspection Gauge, used for maintenance and inspection.
  • the first is the maximum operating pressure of the pipe where the inspection will be carried out, due to the interaction between the fluid, the PIG and the pipe. It is possible to reach pressures above the operating pressure causing major damage to the pipe.
  • the second corresponds to the speed with which the inspection is carried out, since high speeds or accelerations in the path reduce the efficiency of the inspection and increase the possibility of damage to the PIG and the pipeline.
  • the third corresponds to generating pressures below the vapor pressure. In the case of working with liquids, this pressure generates the known phenomenon of cavitation generating damage to the pipe.
  • US Pat. No. 864,544 discloses a method for fluid-driven pipe cleaning without considering the effects that said activity generates on the integrity of the pipe and the inspection option.
  • US Patent 1,547,440 like the previous patent used for cleaning, does not consider its interaction with the pipeline and the possibility of inspection.
  • US Patent 3,292,197 unlike the previous ones, used a Magnetic cleaning system even without taking into account the PIG - pipe interaction.
  • US Patent 3,755,908 discloses a PIG that inspects the pipe wall for deviations in its internal diameter by recording the data mechanically. This patent includes the inspection function without considering the influence of the robot with the pipe.
  • the US patent 6,370,721 B 1, granted in 2002, is composed of a series of passages each with a venturi-like configuration, which allow the fluid to flow through the robot body.
  • the size and shape of the passages may change to vary the pressure drop in the PIG body, varying the speed of the PIG in the pipe.
  • This patent obstructs in a greater percentage the passage of the fluid and does not consider the effect of the robot in the variation of fluid pressure; It also does not have a locomotion system operated by the capture of energy from the fluid, and does not control the contact force of the wheels with the pipe or adapt its shape to it.
  • US Patent 5,208,936, issued in 1993 discloses a PIG for pipelines and contains a series of holes in the robot body with the intention of allowing the passage of gas through the PIG body. The speed is controlled with a turntable that obstructs or allows the passage of gas through the body of the PIG.
  • This patent obstructs the passage area of the fluid to a greater extent and is only for gas.
  • the disclosed PIG cannot interact in different fluids (liquids or gases), nor does it have a locomotion mechanism nor does it consider the robot's influence on the gas flow and its pressure. Finally, it does not control the contact force with the pipe or adapt its shape to it.
  • Patent GB 2,305,407 granted in 2005, discloses a locomotion system and obtains the energy for its locomotion from the energy of the fluid. Said energy is taken by means of a turbine composed of a stator and a rotor, and is taken to a screw cam system which transforms the turbine's rotation movement into a cyclic translation movement which acts on brushes that they lean on the walls of the pipe generating their own locomotion.
  • the turbine is located in the center of the pipe and has a Kaplan type configuration. It does not take into account the influence of the PIG in the variation of fluid pressure inside the pipe and does not control the contact force with the pipe or adapt its shape to it.
  • US Patent 7,182,025 B2, granted in 2007, discloses a robot for pipes from 2 to 6 inches in diameter, presents a power take-off system by means of a turbine, passages in the robot body and a helical movement mechanism.
  • the PIG is limited for operation in pipes up to 6 inches. Nor does it consider the robot's influence on the pressure of the fluid in the pipe, and does not control the contact force of the wheels with the pipe or adapt its shape to it.
  • Figure 1 is a sectional view of the Robot.
  • Figure 2 is a turbine for harnessing the energy of the fluid.
  • Figure 3A is a normal force generation system.
  • Figure 3B is the detail of the normal force generation mechanism.
  • Figure 4 is the front view of the power generation system and adaptation of various geometries for 4 contact points or supports.
  • Figure 5 is the front view of the power generation system and adaptation of various geometries for 3 contact points or supports.
  • Figure 6 shows the steering system for the robot.
  • Figure 7 shows the robot control scheme for inspection.
  • Figure 8 shows the complete assembly of the robot for inspection. 4. Brief description of the invention
  • the present invention consists of an inspection robot for pipes that carry different types of fluids (liquids or gases).
  • the robot considers the interaction between the fluid, the pipe and the robot, in order to avoid overpressures in the pipe above the maximum operating pressures and the pressure drops below the vapor pressure, thus preventing the Cavitation in the case of liquids.
  • the robot takes the energy from the fluid and with it generates its own locomotion also controlling its speed so that it can move at a constant speed eliminating the speed variations typical of fluid transport.
  • the robot of the present invention allows the incorporation of different inspection techniques making it flexible to the use of different types of instrumentation.
  • the constant and reconfigurable speed is achieved through the control system which is responsible for maintaining the speed at a reference value and assessing the interaction between the robot, the pipe and the fluid in order to maintain safe operating conditions (avoid overpressures, vapor pressures or sudden changes in speed).
  • the robot of the present invention consists of 5 main systems:
  • the tubular body of the robot is described.
  • the tubular body of the robot is placed inside the pipe where the inspection will be carried out so that the axis of the tubular body is parallel to the longitudinal axis of fluid flow.
  • the robot of the present invention is contemplated for pipes that carry different types of fluids (liquids or gases) inside.
  • the tubular body consists of at least two modular sections joined through a smaller diametral section (8), where a system for taking energy from the fluid flow is located. Each section has a series of clamping mechanisms that allow the union between said sections.
  • the tubular body has essentially conical sections found which together adopt a venturi-like shape. This configuration is determined by the input contraction (1), a throat section (2) and an output expansion (3). This configuration of sections harness the energy of the fluid generating a venturi effect.
  • the body shape of the venturi-type robot allows the flow energy to be exchanged for kinetic energy of the fluid, increasing the same in the throat section (2) of the system, where a system is located to take energy from the flow of the fluid coupled to the tubular body.
  • This system for taking the kinetic energy of the flow to convert it into rotational mechanical energy in the preferred mode is a turbine (9) (illustrated in Figure 2).
  • the shape of the tubular body of the robot also intervenes in the thrust force generated by the fluid and allows a flow to the outlet with decrease of the possible vortices generated by the internal geometry of the robot body.
  • the turbine (9) and the normal and steering force generation system are integral, so that when the flow of fluid passes through the robot, the turbine (9) moves harmoniously at the same time as the mentioned systems and these in turn drive the entire tubular body of the robot.
  • the cylindrical configuration of the tubular body of the robot shown in Figure 1 and the venturi-like configuration in the inner part of the tubular body allows to house an inspection system (5).
  • the inspection system (5) can perform the inspection of the pipe according to need; It can be geometric, visual, pipe thickness, corrosion, coating thickness, etc.
  • the instrumentation equipment can be located in the inspection area (5) around the pipe.
  • MFL Magnetic Flux Lekage
  • Any type of instrumentation necessary to make these measurements is adapted in the robot body, specifically in the inspection system chamber (5).
  • the inspection is geometric, probes or inductive sensors are used. Therefore, the present invention acts as a platform for different inspection techniques.
  • the tubular body of the robot has a plurality of discs (6) that facilitate the movement of the robot through the pipe.
  • These disks (6) usually they have the same diameter to the nominal diameter of the pipe where they are going to move, this with the purpose of generating a radial interference and a pressure force between the disks and the pipe and thus allow the axial alignment of the robot inside the pipe.
  • the discs (6) generate a force opposite to the direction of movement as a function of the radial interference between the discs and the pipe. Said force is compensated by the normal force generation system and the helical locomotion system, contemplated by the robot's motion control system.
  • a system is described, to take the energy from the fluid flow in order to convert it into mechanical energy, which consists of a turbine (9).
  • the turbine (9) is responsible for taking the flow energy from the throat section (2) (see Figure 1) to convert it into rotational mechanical energy.
  • the angle of the blades (11), its shape and the diameter of the turbine is variable depending on the fluid through which it is transported and the diameter of the pipe in order to obtain the speed of rotation appropriate to the needs of the inspection To make. For example, for a pipe that carries water, Kaplan turbine blades are used; For gas transport, the blades have the shape of gas turbines while retaining a similar geometry.
  • the normal force generation system is responsible for generating the contact force between the robot and the pipe to allow helical locomotion. Said locomotion depends on the generation of normal force on the pipe and the angle (16) of the selective friction points which gives the advance and translation speed.
  • the selective direction points can be formed by any element that allows the bearing between the robot and the pipe walls, which in preferred embodiments of the present invention are addressable wheels (7). For example, so that the robot can reach a speed of 5m / s, the angle ⁇ can vary between [-45 to 45] degrees, where said angle is a function of the desired inspection speed.
  • the normal force generation system consists of a set of articulated bars (13) driven by a motor that governs a gear system (17) and cogwheel (18).
  • This gear system which is part of the normal force generation system, is responsible for transmitting the force to the articulated bars (13) which in turn generate the force on the walls of the pipe.
  • the gears (17) can be conical, straight or helical, with the straight gears being the preferred embodiment of the present invention.
  • a screw (14), shown in Figure 3B is integral to the gear (17) and nut (15), which are responsible for opening and closing the mechanism of articulated bars (13) increasing the contact force between the robot and the pipe also adapting it to geometric variations present in pipes of the same commercial standard diameter.
  • the force generation system is integral to the turbine (9) rotating with it, taking advantage of the flow energy, as shown in Figure 1 (9) and (7).
  • the normal force generation system can be driven by a stepper motor or a servomotor that acts on the gearwheel (18) that transmits movement to the gear system (17) that rotates the screws (14) inside the nut (15) which is free and moves on the axis of the screw, moving the articulated bars (13) acting on the wheels (7) which adjust the value of the normal force to a value that can range from 0 to 30,000 N depending on the boundary conditions of the pipe to be inspected.
  • the force generation system can have at least 3 points of contact with the pipe as shown in Figure 4 where four points of contact (19a), (19b), (19c), (19d) and Figure 5 are presented which shows three points of contact (20a), (20b), (20c).
  • Variations in the force generated by the normal force generation system can increase or decrease its contact diameter by 5%.
  • the person versed in the matter would understand that other designs can be seen that allow to generate normal force on the internal surface of the pipe, such as springs, pneumatic, hydraulic systems, auger.
  • the steering system for the robot is described.
  • the robot's steering system works in conjunction with the normal force system, but for purposes of understanding the figure, it does not include the sprocket (18) shown in Figure 3 ⁇ , which would go around on the front face, opposite to the cogwheel (22) that is on the back side and that makes contact with the gears (21), which is responsible for rotating the gears (17) and modifying the force of the wheels on the pipe.
  • the steering system shown in Figures 1, 3, 6 and 8, is responsible for changing the orientation of the wheels (7) of the robot forming an angle of attack ⁇ (16) (see Figures 3 and 6), defined as the angle (16) between the wheels of the robot and the pipe, generating a helical movement which transforms the rotational movement of the turbine into longitudinal movement along the pipe, something similar to how a screw and a nut would.
  • the angle of attack (16) changes depending on the desired speed of movement of the robot.
  • the steering system is initially driven by a conductive cogwheel (22) (see Figure 6) driven by a servomotor or stepper motor. When turning, the cogwheel (22) drives the driven gear system (23), which by means of a cardan (24) transmits the angular movement to the addressable wheels (7) of the robot.
  • the robot control system is responsible for maintaining the speed at a reference value Vd (t) taking into account the interaction between the fluid, the pipe and the robot.
  • the control system is a system based on the thrust force necessary to maintain the translation in the reference value and the monitoring of the interaction between the robot, the pipe and the fluid so as not to reach unwanted pressure values.
  • the control system takes the speed reference value Vd (t), then through a comparator (29) generates the error signal E (t) which is transformed to normal force and angle of the addressable wheels F (t ) by means of the gain (30) by changing the movement of the robot, whose dynamic equation (3) is in the RIT (31) (acronym for Robot for Pipe Inspection).
  • This movement generates a pressure signal P (x, t) that modifies the pressure conditions P (x, t) and fluid velocity V (x, t) preset in the control, reflected in (32). Due to the interaction of the plant (Fluid Pipe Interaction) + RIT (Pipe Inspection Robot) (32), the thrust force on the RIT robot (33) is changed generating a new angle of the addressable wheels and normal force F (t) and therefore its speed.
  • Figure 8 shows the configuration of the inspection robot in its preferred mode with all its systems, tubular body (27), contact discs (6), turbine (9) and helical locomotion system (26).
  • the robot's electronic system is divided into two parts: the electronics for the control and the electronics for instrumentation or electronics used in the inspection, the latter depends on the service that is requested, for example if it is corrosion detection it is necessary to use an MFL system (Magnetic field leakage), if it is a geometric detection, you need probes or inductive sensors, these systems are located in the body of the robot in the area of the inspection system (5) according to the requested need.
  • the control electronics consist of an odometer or encoder that gives the robot speed information.
  • the controller can be of any technology such as DSP, FPGA, microcontroller, etc.
  • the controller can be of any technology such as DSP, FPGA, microcontroller, etc.
  • the second servomotor acts on the helical transmission system (see Figure 6) by controlling the angle (16) of incidence of the addressable wheels (7) of the robot with the pipe by changing the travel speed of the robot.
  • the controller analyzes the influence of the robot on the pressures and velocities of the fluid, since it generates changes in the flow behavior and this in turn generates changes in the drag force that acts on the robot influencing its speed.
  • the robot performs an inspection on a pipeline that carries oil.
  • the first step is to make a route through the pipeline to be inspected in order to obtain the plani-altimetric information of the route, inferring the position from equation (4):

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Manipulator (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Abstract

La présente invention concerne un robot d'inspection de canalisations transportant différents types de fluides (liquides ou gaz). Ce robot prend en compte l'interaction entre le fluide, la canalisation et le robot, dans le but d'éviter les surpressions dans la canalisation au-delà des pressions maximales de fonctionnement et les chutes de pression en-dessous de la pression de vapeur, et de prévenir ainsi la cavitation dans le cas des liquides. Le robot prélève l'énergie du fluide pour générer sa propre locomotion en régulant sa vitesse de manière à pouvoir se déplacer à vitesse constante, en supprimant les variations de vitesses caractéristiques du transport de fluides. Cette vitesse constante et reconfigurable est réalisée au moyen d'un système de commande chargé de maintenir la vitesse à une valeur de référence et d'évaluer l'interaction entre le robot, la canalisation et le fluide afin de maintenir des conditions de fonctionnement sûres.
PCT/CO2013/000001 2012-05-11 2013-05-14 Plate-forme robotique pour inspection interne de canalisations Ceased WO2013167094A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CO12078006 2012-05-11
CO12078006A CO6790240A1 (es) 2012-05-11 2012-05-11 Plataforma robótica para inspección interna de tuberias

Publications (2)

Publication Number Publication Date
WO2013167094A2 true WO2013167094A2 (fr) 2013-11-14
WO2013167094A3 WO2013167094A3 (fr) 2014-02-20

Family

ID=49551384

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CO2013/000001 Ceased WO2013167094A2 (fr) 2012-05-11 2013-05-14 Plate-forme robotique pour inspection interne de canalisations

Country Status (2)

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CO (1) CO6790240A1 (fr)
WO (1) WO2013167094A2 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3057052A1 (fr) * 2016-10-04 2018-04-06 Commissariat A L'energie Atomique Et Aux Energies Alternatives Dispositif robotique mobile avec mecanisme de propulsion a vis d'archimede ameliore
EP3671204A1 (fr) * 2018-12-19 2020-06-24 Cokebusters Limited Racleur d'inspection d'un objet tubulaire
WO2023007299A3 (fr) * 2021-07-30 2023-03-09 Ptt Exploration And Production Public Company Limited Dispositif pour se déplacer dans une canalisation

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4055315A (en) * 1976-04-14 1977-10-25 Gvelesiani Konstantin Shalvovi Device for pipeline transportation of loads by fluid flow
GB9617115D0 (en) * 1996-08-15 1996-09-25 Astec Dev Ltd Pipeline traction system
US6370721B1 (en) * 2000-10-03 2002-04-16 Tuboscope I/P, Inc. Variable speed pig for pipeline applications
CA2440344C (fr) * 2001-03-07 2007-06-26 Carnegie Mellon University Systeme de controle robotique de conduites de gaz
GB0206246D0 (en) * 2002-03-15 2002-05-01 Weatherford Lamb Tractors for movement along a pipepline within a fluid flow
US8650694B2 (en) * 2008-07-03 2014-02-18 Tdw Delaware, Inc Speed regulated pipeline pig
CA2732387C (fr) * 2008-07-31 2019-01-15 On Stream Technologies Inc. Racleur pour tuyau et procede de nettoyage de tuyau
GB2469058A (en) * 2009-03-31 2010-10-06 Ind Brushware Ltd Pipe cleaning apparatus
KR101103805B1 (ko) * 2009-08-06 2012-01-06 한전케이피에스 주식회사 착탈가능한 탐촉자를 구비한 검사장치

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3057052A1 (fr) * 2016-10-04 2018-04-06 Commissariat A L'energie Atomique Et Aux Energies Alternatives Dispositif robotique mobile avec mecanisme de propulsion a vis d'archimede ameliore
WO2018065710A1 (fr) * 2016-10-04 2018-04-12 Commissariat A L'energie Atomique Et Aux Energies Alternatives Dispositif robotique mobile avec mécanisme de propulsion à vis d'archimède amélioré
EP3671204A1 (fr) * 2018-12-19 2020-06-24 Cokebusters Limited Racleur d'inspection d'un objet tubulaire
WO2023007299A3 (fr) * 2021-07-30 2023-03-09 Ptt Exploration And Production Public Company Limited Dispositif pour se déplacer dans une canalisation

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Publication number Publication date
WO2013167094A3 (fr) 2014-02-20
CO6790240A1 (es) 2013-11-14

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