Tbm main drive visualized lubrication apparatus and method of use thereof
By designing a visual lubrication device for the TBM main drive, the problems of difficulty in observing the amount of lubricating oil and inconvenience in replacing it were solved. This achieved efficient storage and heat dissipation of the lubricating fluid, improving the service life of the TBM drive components and the digging efficiency.
Patent Information
- Application Number
- CN202310833763.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-10
- Publication Date
- 2025-12-05
- Estimated Expiration
- 2043-07-10
AI Technical Summary
Existing TBM drive lubrication systems cannot monitor the lubricating oil level at all times, leading to insufficient lubrication, component wear, and inconvenient replacement, which affects digging efficiency.
A TBM main drive visualization lubrication device was designed. A sealed space is formed by a sealed shell and a support mechanism. The lubricant content can be observed through a transparent tube. The lubricant is continuously injected through an injection pipe, and the liquid volume is controlled by a drain pipe. A coupling connects to a motor drive gear to achieve efficient storage and heat dissipation of the lubricant.
It achieves efficient lubrication and heat dissipation of TBM drive components, avoids wear, facilitates the disassembly and maintenance of functional components, and improves digging efficiency.
Smart Images

Figure CN117108903B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of construction equipment technology, specifically a TBM main drive visual lubrication device and its usage method. Background Technology
[0002] TBM stands for Tunnel Boring Machine, which is widely used in industries such as railway tunnels, water conservancy tunnels, and urban subways. However, in recent years, new types of TBMs such as inclined shaft TBMs, vertical shaft TBMs, micro TBMs, ultra-large diameter TBMs, composite TBMs, and irregular cross-section TBMs have begun to be developed and applied. They are making great progress in application fields and will be vigorously promoted after the technology matures.
[0003] However, in existing technologies, most TBM drive lubrication is spray-type, and only a small amount of lubricating oil remains inside the existing TBM drive. Furthermore, lubrication is only performed on the rotating parts of the existing TBM drive during the tunneling process. In actual tunneling, it is impossible to actively and continuously observe the oil level inside the existing TBM drive. This can easily lead to excessive wear of the internal functional components of the existing TBM drive when the oil level is too low. Since the structure of the existing lubrication functional components is relatively fixed, it is not easy to replace the worn functional components, resulting in poor actual equipment performance and significantly affecting the overall excavation efficiency. Summary of the Invention
[0004] The purpose of this invention is to provide a TBM main drive visual lubrication device and its usage method that can fully lubricate and dissipate heat from existing TBM drive functional parts, allow for real-time and intuitive observation of lubricating oil levels, and facilitate the maintenance and replacement of existing TBM drive functional parts.
[0005] The technical solution adopted in this invention is as follows: A TBM main drive visual lubrication device, comprising: a functional mechanism, the functional mechanism including a first sealing shell, a second sealing shell, and a limiting component; one end of the second sealing shell extends into the interior of the first sealing shell; a liquid measuring frame is fixedly connected to one outer surface of the first sealing shell; a liquid guide tube, a liquid injection tube, and a liquid drain tube penetrate one outer surface of the first sealing shell; one end of the liquid guide tube is connected to a transparent tube; one end of the transparent tube extends into the interior of the liquid measuring frame; a turntable is rotatably connected to one inner wall of the first sealing shell; a sealing ring is fixedly connected to one outer surface of the turntable; a connecting plate is sleeved on the outer surface of the sealing ring; a retaining ring is fixedly connected to one outer surface of the connecting plate; and the limiting component is disposed on the turntable; and
[0006] A support mechanism is provided on the first sealing shell. The support mechanism is provided in multiple sets. Each set of the support mechanism includes a connecting rod. A limit ring is threadedly connected to the outer surface of the connecting rod. An extension tube is slidably sleeved on the outer surface of the connecting rod. An elastic block is rotatably connected to one end of the extension tube.
[0007] The injection pipe is connected to an injection check valve at one end, and the drainage pipe is connected to a control valve at one end.
[0008] The second sealing shell and the first sealing shell are fixedly connected by bolts. Multiple connecting pipes are fixedly connected at equal intervals on the outer surface of the first sealing shell, and each connecting pipe is threadedly connected to a corresponding connecting rod.
[0009] The limiting component includes a mounting frame, with a threaded tube rotatably connected between the inner walls of the two sides of the mounting frame. A movable threaded rod is threadedly connected inside the threaded tube, and a worm gear is sleeved on the outer surface of the threaded tube. A worm is rotatably connected to the inner wall of one side of the mounting frame, and the worm and the worm wheel mesh. A connecting gear is sleeved on the outer surface of the worm.
[0010] The mounting frame is fixedly connected to a hydraulic cylinder at its bottom. The output end of the hydraulic cylinder extends into the mounting frame, and a rack is fixedly connected to the output end of the hydraulic cylinder. The rack meshes with a connecting gear.
[0011] The movable threaded rod is fixedly connected to a locking block at one end, and the bottom of the locking block slides through the sealing ring and the connecting plate.
[0012] The first sealing shell has multiple rotating shafts equidistantly connected to the inner wall of one side along the edge. Each rotating shaft has a coupling fixedly connected to the outer surface of one side, and multiple tension rings are sequentially fitted onto the outer surface of each rotating shaft.
[0013] Among them, multiple abutment plates are equidistantly rotatably connected to the inner surface wall of one side of the second sealing shell along the edge direction.
[0014] The second sealing shell has a leak-proof ring threaded onto one side of its outer surface.
[0015] A method for using a TBM main drive visual lubrication device includes the following steps:
[0016] S1. Installation and splicing: The first and second sealing shells can be fitted onto the outside of the existing TBM drive. By rotating the limiting ring, the position of the extension tube can be moved and adjusted under the support of the connecting rod. This allows the extension tube to be pressed against the inner wall of the existing TBM equipment with the help of the elastic block. Then, according to the specifications of the existing TBM drive's internal drive gear and gear ring, an extension ring of appropriate diameter is selected. The drive gear of the existing TBM drive is then fitted onto the outer surface of the corresponding extension ring. At the same time, the gear ring of the existing TBM drive is fitted onto the outer surface of the connecting plate. The connecting plate is then securely connected to one end of the existing TBM cutter head.
[0017] S2. Adjustment: A coupling securely connects the rotating shaft to the output of the existing TBM-driven motor. This allows the existing TBM-driven motor to rotate via the coupling, rotating shaft, and extension ring, driving the drive gear. The drive gear then drives the gear ring, which in turn rotates the connecting disc, which in turn rotates the cutterhead. This enables the existing TBM to perform normal excavation operations. Simultaneously, the compression and bonding of the sealing ring and the seepage-proof ring... The sealing ring and connecting plate create a sealed space inside the first and second sealing shells, allowing the equipment to effectively store lubricating fluid. Simultaneously, lubricating fluid can be continuously injected into the sealed space through the injection pipe. With the continuous injection, the lubricating fluid content in the existing TBM drive section can be easily and intuitively observed through a transparent tube. Furthermore, the lubricating fluid content within the sealed space can be dynamically maintained through the drain and injection pipes, enabling efficient heat dissipation and lubrication of the existing TBM drive components, thus preventing wear on these components.
[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:
[0019] In this invention, during use, the first and second sealing shells can be fitted onto the outside of the existing TBM drive. By rotating the limiting ring, the position of the extension tube can be effectively moved and adjusted under the support of the connecting rod. This allows the extension tube to be pressed against the inner wall of the existing TBM equipment with the help of the elastic pad, enabling convenient and stable installation. Then, based on the specifications of the existing TBM drive's internal drive gear and gear ring, an appropriate diameter torque ring is selected. The existing TBM drive's drive gear is then fitted onto the outer surface of the corresponding torque ring, while the existing TBM drive's gear ring is fitted onto the outer surface of the connecting plate. The connecting plate is then securely connected to one end of the existing TBM's cutter head. Simultaneously, a coupling securely connects the rotating shaft to the output end of the existing TBM drive's motor. This allows the existing TBM drive's motor to drive the existing TBM drive's drive gear through the coupling, rotating shaft, and torque ring, thus enabling the existing TBM drive's gear ring to drive the existing TBM drive's gear ring. The rotating ring allows the existing TBM drive gear ring to effectively drive the connecting disc to rotate, which in turn drives the existing TBM cutterhead to rotate, enabling the existing TBM to perform normal excavation. Simultaneously, the compression and bonding of the sealing ring and the anti-seepage ring, along with the obstruction of the sealing ring and the connecting disc, create an effective sealed space within the first and second sealing shells. This allows the equipment to effectively store lubricating fluid, and lubricating fluid can be continuously injected into the sealed space through the injection pipe. As the lubricating fluid is continuously injected, the lubricating fluid content in the existing TBM drive section can be easily and intuitively observed through a transparent tube. The drainage and injection pipes dynamically maintain the lubricating fluid content within the sealed space, enabling efficient heat dissipation and lubrication of the existing TBM drive components, effectively preventing wear. Furthermore, the equipment can be easily disassembled and reassembled based on actual wear conditions, allowing the equipment to efficiently perform its intended functions. Attached Figure Description
[0020] Figure 1 This is a frontal perspective view of the present invention;
[0021] Figure 2 This is a rear perspective view of the present invention;
[0022] Figure 3 This is a frontal sectional perspective view of the present invention;
[0023] Figure 4 This is a frontal sectional view of the functional mechanism of the present invention.
[0024] Figure 5 For the present invention Figure 4 Enlarged view of section A in the middle;
[0025] Figure 6 This is a rear sectional view of the functional components of the present invention.
[0026] Figure 7 This is a frontal sectional view of the support mechanism of the present invention.
[0027] The diagram shows the following markings: 1. Functional Mechanism; 101. First Sealing Shell; 102. Connecting Pipe; 103. Liquid Guide Pipe; 104. Transparent Pipe; 105. Liquid Measuring Frame; 106. Injection Pipe; 107. Drainage Pipe; 108. Rotating Shaft; 109. Turntable; 110. Sealing Ring; 111. Connecting Plate; 112. Adhesive Ring; 113. Mounting Frame; 114. Threaded Pipe; 115. Moving Threaded Rod; 116. Locking Block; 117. Worm Gear; 118. Rack; 119. Hydraulic Cylinder; 120. Second Sealing Shell; 121. Support Plate; 122. Leak-proof Ring; 123. Coupling; 2. Support Mechanism; 201. Connecting Rod; 202. Limiting Ring; 203. Extension Pipe; 204. Elastic Adhesive Block. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0029] Example 1
[0030] Reference Figures 1-7A TBM main drive visual lubrication device includes a functional mechanism 1 and a support mechanism 2. The functional mechanism 1 includes a first sealing shell 101, a second sealing shell 120, and a limiting component. The first sealing shell 101, together with the second sealing shell 120, provides a mounting base for other functional components of the device. It also forms an effective storage space with the sealing ring 110, connecting plate 111, adhesive ring 112, and anti-leakage ring 122. One end of the second sealing shell 120 extends into the interior of the first sealing shell 101. A liquid measuring frame is fixedly connected to the outer surface of one side of the first sealing shell 101. The liquid measuring frame 105 effectively prevents the lubricating fluid from expanding due to heat. A liquid guide pipe 103, an injection pipe 106, and a drain pipe 107 penetrate one side of the outer surface of the first sealing shell 101. The liquid guide pipe 103 facilitates the installation of the transparent tube 104. The injection pipe 106, in conjunction with the drain pipe 107, allows for the cyclical injection of a suitable amount of lubricating fluid into the existing TBM drive. One end of the liquid guide pipe 103 is connected to the transparent tube 104, which facilitates direct observation of the lubricating fluid content inside the existing TBM drive. One end of 104 extends into the interior of the volumetric liquid frame 105. A turntable 109 is rotatably connected to the inner wall of one side of the first sealing shell 101. The turntable 109 facilitates the installation of other functional components of the equipment. A sealing ring 110 is fixedly connected to the outer surface of one side of the turntable 109. A connecting plate 111 is fitted onto the outer surface of the sealing ring 110. The connecting plate 111 facilitates a stable connection with the existing cutter head of the TBM. A retaining ring 112 is fixedly connected to the outer surface of one side of the connecting plate 111. A limiting component is provided on the turntable 109, and a support mechanism 2 is provided on the first sealing shell 101. The support mechanism 2 is provided in multiple sets. Each set of support mechanism 2 includes a connecting rod 201. The connection rod 201 facilitates the installation of other functional components of the equipment. The outer surface of the connecting rod 201 is threaded with a limit ring 202. The limit ring 202 can effectively move and adjust the position of the extension tube 203. The extension tube 203 is slidably sleeved on the outer surface of the connecting rod 201. The extension tube 203 can move and adjust the elastic block 204, thereby enabling the equipment to be installed stably. One end of the extension tube 203 is rotatably connected to the elastic block 204.
[0031] Reference Figures 3-7One end of the injection pipe 106 is connected to an injection check valve, which facilitates the injection of lubricating liquid into the equipment. One end of the drain pipe 107 is connected to a control valve, which facilitates the control of the discharge of lubricating liquid, thereby effectively controlling the lubricating liquid content inside the equipment. The second sealing shell 120 and the first sealing shell 101 are fixedly connected by bolts. Multiple connecting pipes 102 are fixedly connected at equal intervals on the outer surface of the first sealing shell 101. The connection pipes 102 facilitate the installation of connecting rods 201. Each connecting pipe 102 and the corresponding connecting rod 201 are threadedly connected. The limiting component includes a mounting frame 113, which facilitates the installation of the connecting rods 201. For the installation and setup of other functional components of the equipment, a threaded tube 114 is rotatably connected between the inner walls of both sides of the mounting frame 113. The threaded tube 114 facilitates the rotational adjustment of the movable threaded rod 115. The movable threaded rod 115 is threadedly connected inside the threaded tube 114, and the movable threaded rod 115 can effectively move the position of the adjustment block 116. A worm gear is fitted on the outer surface of the threaded tube 114, and the worm gear allows the connecting gear to effectively drive the threaded tube 114 through the worm 117. A worm 117 is rotatably connected to the inner wall of one side of the mounting frame 113, and the worm 117 meshes with the worm gear. A connecting gear is fitted on the outer surface of the worm 117. A hydraulic cylinder 119 is fixedly connected to the bottom. The hydraulic cylinder 119 can effectively move and adjust the position of the rack 118, thereby enabling the rack 118 to drive the connecting gear to rotate. The output end of the hydraulic cylinder 119 extends into the mounting frame 113. The output end of the hydraulic cylinder 119 is fixedly connected to the rack 118, which meshes with the connecting gear. One end of the moving threaded rod 115 is fixedly connected to a locking block 116. The locking block 116 can effectively limit the installation position of the gear ring of the existing TBM drive. The bottom of the locking block 116 slides through the sealing ring 110 and the connecting plate 111. Multiple rotating shafts 108 are equidistantly connected to the inner surface wall of one side of the first sealing shell 101 along the edge. The installation of the rotating shaft 108 facilitates the installation of other functional components of the equipment. Each rotating shaft 108 has a coupling 123 fixedly connected to one side of its outer surface. The coupling 123 enables the output end of the existing TBM drive motor to be stably connected to the rotating shaft 108. Multiple tension rings are sequentially fitted onto the outer surface of each rotating shaft 108 to facilitate the installation of different specifications of drive gears of the existing TBM drive. Multiple abutments 121 are equidistantly rotatably connected to the inner wall of one side of the second sealing shell 120 along the edge direction. The abutments 121 can effectively limit the position of the tension rings. A leak-proof ring 122 is threadedly connected to the outer surface of one side of the second sealing shell 120.
[0032] The following provides a detailed description of the usage method of a TBM main drive visual lubrication device provided in the embodiments of the present invention, which includes the following steps:
[0033] Step 1, Installation and Assembly: The first sealing shell 101 and the second sealing shell 120 can be fitted onto the outside of the existing TBM drive. Then, by rotating the limiting ring 202, the position of the extension tube 203 can be effectively moved and adjusted under the support of the connecting rod 201. This allows the extension tube 203 to be pressed against the inner wall of the existing TBM equipment in conjunction with the elastic patch 204, so that the equipment can be installed and set up conveniently and stably. Then, according to the specifications of the drive gear and gear ring inside the existing TBM drive, an extension ring of appropriate diameter is selected. The drive gear of the existing TBM drive is then fitted onto the outer surface of the corresponding extension ring. At the same time, the gear ring of the existing TBM drive is fitted onto the outer surface of the connecting plate 111, and the connecting plate 111 is stably connected to one end of the cutter head of the existing TBM.
[0034] Step 2, Adjustment: The rotating shaft 108 is securely connected to the output end of the existing TBM-driven motor via coupling 123. This allows the existing TBM-driven motor to rotate the drive gear through coupling 123, rotating shaft 108, and the torque extender ring. The drive gear then rotates the gear ring, which in turn effectively drives the connecting disc 111. The connecting disc 111 then effectively rotates the cutterhead of the existing TBM, enabling normal excavation by the existing TBM. Simultaneously, the compression and bonding of the sealing ring 112 and the seepage-proof ring 122, along with the obstruction of the sealing ring 110 and the connecting disc 111, ensure that... The first sealing shell 101 and the second sealing shell 120 can form an effective sealed space, which enables the equipment to effectively store lubricating fluid. At the same time, lubricating fluid can be continuously injected into the sealed space through the injection pipe 106. With the continuous injection of lubricating fluid, the lubricating fluid content of the existing TBM drive part can be conveniently and intuitively observed through the transparent pipe 104. The lubricating fluid content inside the sealed space can be dynamically maintained through the drain pipe 107 and the injection pipe 106, so that the lubricating fluid can effectively perform efficient heat dissipation and lubrication treatment of the existing TBM drive part, effectively preventing wear of the existing TBM drive part. At the same time, the equipment can be easily disassembled and assembled according to the actual wear condition, so that the equipment can efficiently realize its intended functions.
[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A TBM main drive visualization lubrication apparatus, characterized by, Include: Functional mechanism (1), the functional mechanism (1) includes first sealed shell (101), second sealed shell (120) and limiting component, one end of the second sealed shell (120) extends to the inside of the first sealed shell (101), the outer surface of one side of the first sealed shell (101) is fixedly connected with the liquid measuring frame (105), the outer surface of one side of the first sealed shell (101) is penetrated by the liquid guide pipe (103), the liquid injection pipe (106) and the liquid discharge pipe (107), one end of the liquid guide pipe (103) is communicated with the transparent tube (104), one end of the transparent tube (104) extends to the inside of the liquid measuring frame (105), the inner wall of one side of the first sealed shell (101) is rotatably connected with the rotating disc (109), the outer surface of one side of the rotating disc (109) is fixedly connected with the sealing ring (110), the outer surface of the sealing ring (110) is sleeved with the connecting disc (111), the outer surface of one side of the connecting disc (111) is fixedly connected with the paste ring (112), and the limiting component is arranged on the rotating disc (109); and Support mechanism (2), the support mechanism (2) is arranged on the first sealed shell (101), a plurality of groups of the support mechanism (2) are arranged, each group of the support mechanism (2) comprises a connecting rod (201), the outer surface of the connecting rod (201) is threadedly connected with a limiting ring (202), the outer surface of the connecting rod (201) is slidably sleeved with an extension pipe (203), and one end of the extension pipe (203) is rotatably connected with an elastic paste block (204).
2. A TBM main drive visualized lubrication apparatus as claimed in claim 1, characterized in that: The liquid injection pipe (106) is provided with a liquid injection one-way valve at one end, and the liquid discharge pipe (107) is provided with a control valve at one end.
3. A TBM main drive visualized lubrication apparatus as claimed in claim 2, characterized in that: The second sealed shell (120) and the first sealed shell (101) are fixedly connected by bolts, and the outer surface of the first sealed shell (101) is equidistantly fixedly connected with a plurality of connecting pipes (102), each connecting pipe (102) and the corresponding connecting rod (201) are respectively threadedly connected.
4. A TBM main drive visualized lubrication apparatus as claimed in claim 3, characterized in that: The limiting component comprises a mounting frame (113), the inner walls of the opposite sides of the mounting frame (113) are rotatably connected with a threaded pipe (114), the threaded pipe (114) is internally threadedly connected with a movable threaded rod (115), the outer surface of the threaded pipe (114) is sleeved with a worm gear, the inner wall of one side of the mounting frame (113) is rotatably connected with a worm (117), the worm (117) is engaged with the worm gear, and the outer surface of the worm (117) is sleeved with a linkage gear.
5. A TBM main drive visualized lubrication apparatus as claimed in claim 4, characterized in that: The bottom of the mounting frame (113) is fixedly connected with an oil cylinder (119), the output end of the oil cylinder (119) extends to the inside of the mounting frame (113), and the output end of the oil cylinder (119) is fixedly connected with a rack (118), and the rack (118) is engaged with the linkage gear.
6. A TBM main drive visualized lubrication apparatus as claimed in claim 5, characterized in that: One end of the movable threaded rod (115) is fixedly connected with a clamping block (116), and the clamping block (116) is slidably penetrated through the sealing ring (110) and the connecting disc (111).
7. A TBM main drive visualized lubrication apparatus as claimed in claim 6, characterized in that: The inner wall of the first sealing shell (101) is rotatably connected with a plurality of rotating shafts (108) at equal intervals along the edge, and the outer surface of each rotating shaft (108) is fixedly connected with a shaft coupling (123), and the outer surface of each rotating shaft (108) is sequentially sleeved with a plurality of distance increasing rings.
8. A TBM main drive visualized lubrication apparatus as claimed in claim 7, characterized in that: The inner wall of the second sealing shell (120) is rotatably connected with a plurality of abutting discs (121) at equal intervals along the edge.
9. A TBM main drive visualized lubrication apparatus as claimed in claim 8, characterized in that: The outer surface of the second sealing shell (120) is threadedly connected with an anti-seepage ring (122).
10. A method of using a TBM main drive visualization lubrication apparatus, characterized by, The application is applied to the TBM main drive visualization lubrication equipment in claim 9, and includes the following steps: S1, installation splicing: the first sealing shell (101) and the second sealing shell (120) can be sleeved on the existing TBM drive outside, and then the use position of the extension pipe (203) can be moved and adjusted under the support of the rotating limiting ring (202) at the position of the connecting rod (201), so that the extension pipe (203) can be extruded and attached to the inner wall of the existing TBM device through the elastic attachment block (204), and then the appropriate diameter of the distance increasing ring is selected according to the specifications of the driving gear and the gear ring inside the actual existing TBM drive, and then the driving gear of the existing TBM drive is sleeved on the outer surface of the corresponding distance increasing ring, and the gear ring of the existing TBM drive is sleeved on the outer surface of the connecting disc (111), and the connecting disc (111) is stably connected with one end of the cutter head of the existing TBM; S2, use adjustment: the rotating shaft (108) can be stably connected with the output end of the motor equipment of the existing TBM drive through the shaft coupling (123), so that the motor equipment of the existing TBM drive can drive the driving gear of the existing TBM drive to rotate through the shaft coupling (123), the rotating shaft (108) and the distance increasing ring, so that the driving gear of the existing TBM drive can drive the gear ring of the existing TBM drive to rotate, so that the rotating gear ring of the existing TBM drive can drive the connecting disc (111) to rotate, so that the connecting disc (111) can drive the cutter head of the existing TBM to rotate, so that the existing TBM can be normally used for excavation, and at the same time, under the extrusion and attachment of the gasket (112) and the anti-seepage ring (122) and the blocking of the sealing ring (110) and the connecting disc (111), a sealed space can be formed in the first sealing shell (101) and the second sealing shell (120), so that the equipment can effectively store the lubricating liquid, and the lubricating liquid can be continuously injected into the sealed space through the liquid injection pipe (106), and the content of the lubricating liquid in the existing TBM drive part can be conveniently and intuitively observed through the transparent pipe (104), and the content of the lubricating liquid in the sealed space can be dynamically maintained through the liquid discharge pipe (107) and the liquid injection pipe (106), so that the lubricating liquid can effectively perform efficient heat dissipation and lubrication treatment on the existing TBM drive part, and wear of the existing TBM drive part is avoided.
Citation Information
Patent Citations
Heading machine and main drive lubricating system thereof
CN114060705A
A remote control installation for the pressure of the oil in the pipes conducted to the lubrication points of pressure lubrication appliances.
ES343571A1