CN216433423U - Oil pressure shock absorber leakproofness detection device - Google Patents

Abstract

The utility model discloses an oil hydraulic shock absorber leakproofness detection device. The utility model comprises a box body, a vacuum pump and an evacuation valve; the pumping hole of the vacuum pump is connected with the inner cavity of the box body through a pumping-out valve; in the working process, the inner cavity of the box body is sealed with the external environment; the tank can be loaded with the oil damper to be tested for tightness and the oil damper is in an environment below the standard atmospheric pressure. The utility model discloses can be for the vacuum leakproofness testing environment of oil damper to utilize oil damper's inside and outside pressure differential to realize oil damper seal reliability's short-term test. In addition, the utility model is provided with the tooling plate with an inclined placing position, when the oil pressure damper is placed on the tooling plate, the oil pressure damper is kept in an inclined downward posture; the inner side of the guide sealing part which is most easy to have the problem of sealing performance in the oil pressure shock absorber is completely soaked by oil, and the sealing detection effect is improved.

Description

Oil pressure shock absorber leakproofness detection device

Technical Field

The utility model belongs to the technical field of oil hydraulic shock absorber for rail locomotive vehicle. Specifically, the utility model relates to a leakproofness detection device for rail rolling stock oil damper.

Background

A typical prior art oil pressure shock absorber is shown in fig. 1, and comprises a reserve tube component, a piston rod and an outer casing, and the parts related to leakage are a guide sealing part 1 on the reserve tube component, a reserve tube cylinder 2, a reserve tube welding seam 3 and a reserve tube end cover 4. Before the shock absorber is assembled, the oil leakage defects caused on the oil storage cylinder barrel 2, the oil storage cylinder welding line 3 and the oil storage cylinder end cover 4 can be identified and controlled through nondestructive flaw detection and air tightness inspection, and after the shock absorber leaves a factory, the oil leakage faults at the parts are almost zero; the sealing function of the guide sealing part 1 is realized after the shock absorber is assembled, the oil leakage fault of the part is caused by the defects of the parts and the poor process in the assembling process, after the shock absorber leaves a factory, the shock absorber is vibrated in transportation and stored for a long time, and the oil leakage condition of the shock absorber occasionally occurs before loading; at present, a quick and effective inspection means is not available, and the shock absorber with the quality defect of sealing and high oil leakage risk is identified before leaving a factory.

Two common sealing part structures and leakage modes of the oil pressure damper are schematically shown in FIGS. 2a and 2 b; FIG. 2a illustrates a seal configuration of a wave oil seal + O-ring; figure 2b illustrates the seal configuration of the backbone oil seal + O-ring. In the sealing structure of fig. 2a, the corrugated oil seal is composed of a bottom plate 2-1, a corrugated part 2-2 and a main sealing sleeve 2-3; in the sealing structure of fig. 2b, the framework oil seal is composed of frameworks 2-4 and a main seal 2-5. The factors causing the oil leakage of the shock absorber are:

1. the O-shaped ring has unreasonable line diameter size, material shortage on the surface, unsmooth parting surface, dislocation of an upper die and a lower die and the like, and the O-shaped ring is sheared due to improper operation in the assembling process.

2. The corrugated oil seal has large inner diameter and small outer diameter of the main seal, damaged sealing edges, cracked corrugated parts and the like, a base plate deflects or is not pressed tightly during assembly, and a hoop is not installed on the outer diameter of the main seal.

3. The framework oil seal has the advantages that the size of a sealing edge is large, the sealing edge is damaged, and the like, and the sealing surface is damaged due to the fact that the sealing edge is not compressed or is not compressed properly in the axial direction during assembly.

The oil pressure damper of the rail locomotive is divided into two states: newly manufactured and overhauled. The sealing parts used by the newly manufactured shock absorber and the overhaul shock absorber are new parts, and the states of the sealing parts are completely the same; the greatest difference between them lies in: parts used for overhauling the shock absorber are already used, and the states of other parts are changed. Besides being related to sealing elements, the oil leakage of the overhauling shock absorber is also related to the states of other parts, such as scratches and roughness on the surface of a piston rod, local deformation of a storage cylinder and the like. After the product is assembled, the product is placed statically for a certain time, part of the product has oil leakage and can be identified and isolated, and the other part of the product does not show oil leakage faults before leaving the factory.

In order to reduce the problem of oil leakage of products before loading, partial enterprises take measures:

1. the electric heating leakage method is shown in figure 3, a certain number of assembled shock absorbers are placed in an oven or a tunnel furnace 5, an electric heating pipe 6 is arranged in a box body, the temperature of the box body is increased and heat is conducted to the shock absorbers 7 through a resistance heating method, the gas is stored in the shock absorbers and expands when heated, the internal pressure of the shock absorbers is increased, the internal pressure is higher than the external environment pressure, and oil liquid is forced to generate a leakage tendency through the pressure difference between the inside and the outside.

2. A mechanical temperature rise leakage method is shown in a schematic diagram, the device can be a crank-slider mechanism, a slider 9 is driven to do reciprocating linear motion through a crank 8, and other devices capable of achieving reciprocating linear motion can also be used.

In both of the two leakage methods, the temperature of the shock absorber is increased, so that the volume of the internal air is expanded, pressure higher than the outside is generated, pressure difference is established, the shock absorber is forced to generate leakage, once sealing fails, oil liquid leaks to the outside from the sealing part, and then whether the shock absorber leaks oil is judged through visual observation.

The problems existing in the prior art are as follows: (1) the electric heating leakage method takes about 3 hours from heating, heat preservation to cooling, and has long time and high energy consumption; (2) the mechanical temperature rise leakage method has the advantages that single-branch operation is carried out for about 5-7 minutes, efficiency is low, and in the operation process, if centering is not good during installation of the shock absorber, the risk that a piston rod is damaged by pulling or bending exists, and part of the shock absorber is damaged.

Disclosure of Invention

An object of the utility model is to provide an oil pressure shock absorber leakproofness detection device.

The utility model comprises a box body, a vacuum pump and an evacuation valve; the air suction port of the vacuum pump is connected with the inner cavity of the box body through an evacuation valve; in the working process, the inner cavity of the box body is sealed with the external environment; the tank can be loaded with the oil damper to be tested for tightness and the oil damper is in an environment below the standard atmospheric pressure.

Preferably, the utility model also comprises a tooling plate; the tooling plate can be arranged in the box body; the top of the tooling plate is provided with an inclined placing position; the inclined placement positions are used for placing the oil pressure shock absorbers, so that the shock absorbers are kept in an inclined state in the detection process.

Preferably, the box body is provided with a box door; the door can be opened or closed under powered element or manual control.

Preferably, the door is sealed with a side opening of the cabinet by a rubber seal in a closed state.

Preferably, the bottom of the inner cavity of the box body is provided with a roller slideway taking the box door as a starting point; the bottom of the tooling plate is provided with a sliding plate; the tooling plate can slide into or out of the box body along the roller slideway.

Preferably, a roller slide connected to the door of the cabinet is provided at an outer side of the cabinet.

Preferably, the door has a double-layer or multi-layer structure.

Preferably, the utility model also comprises a pressure sensor and a vacuum gauge; the detection ports of the pressure sensor and the vacuum gauge are connected with the inner cavity of the box body.

Preferably, the utility model also comprises an air break valve; and the air outlet of the air break valve is connected with the inner cavity of the box body.

The utility model has the advantages that:

the utility model discloses can be for the vacuum leakproofness testing environment of oil damper to utilize oil damper's inside and outside pressure differential to realize oil damper seal reliability's short-term test. In addition, the utility model is provided with a tooling plate with an inclined placing position, when the oil pressure shock absorber is placed on the tooling plate, the oil pressure shock absorber is kept in an inclined downward posture; the inner side of the guide sealing part which is most easy to have the problem of tightness in the oil pressure shock absorber is completely soaked by oil, the sealing detection effect is improved, and the oil pressure shock absorber with the problem of tightness is prevented from being subjected to false detection or missed detection.

Drawings

FIG. 1 is a schematic diagram of an oil leakage portion of a typical conventional oil damper;

FIG. 2a is a schematic view of a first exemplary pilot seal arrangement and leakage path;

FIG. 2b is a schematic view of a second exemplary pilot seal configuration and leakage path;

FIG. 3 is a schematic view of a conventional testing apparatus for the leakage method by electric heating;

FIG. 4 is a schematic diagram of a testing apparatus used in a conventional mechanical elevated temperature leak method;

fig. 5 is a schematic structural diagram of the present invention.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

As shown in fig. 5, the device for detecting the sealing performance of the oil damper includes a box 101, a vacuum pump 102, an evacuation valve 103, a vacuum break valve 104, a pressure sensor 105, a vacuum gauge 106, a tooling plate 107, and a controller. The evacuation valve 103 is an electromagnetic on-off valve. The box body 101 is in a cuboid shape and is divided into an inner cavity and a shell, the inner cavity of the box body is required to be completely sealed, the air leakage phenomenon cannot occur at other parts except a pipeline, reinforcing ribs are additionally arranged in the inner cavity, and the box body cannot deform when being pressed; a box door is arranged at the side part of the box body; the box door can be opened or closed under the control of a power element or a person; the box door is sealed with the side opening of the box body through a rubber sealing strip in a closed state; the box door adopts a double-layer structure, and cannot deform when being pressed.

The box 101 is provided with an air pressure detection port, a vacuum detection port, an air inlet and a vacuum pumping port. The extraction opening of the vacuum pump 102 is connected with the vacuum extraction opening on the box body 101 through a metal pipeline; the metal pipeline is connected with an evacuation valve 103 in series; the pressure sensor 105, the vacuum gauge 106 and the vacuum breaking valve 104 are respectively connected with an air pressure detection port, a vacuum detection port and an air inlet which are arranged on the box body 101. The control interfaces of the evacuation valve 103 and the air breaking valve 104 are both connected with the controller; the motor in the vacuum pump 102 is connected to the controller through a motor driver. The signal output interfaces of the pressure sensor 105 and the vacuum gauge 106 are connected with the controller, so that the vacuum degree control in the box body 101 is realized by matching the vacuum pump 102 and the evacuation valve 103. The controller can be a PLC or other control module capable of realizing functions.

The tooling plate 107 is placed at the bottom of the interior cavity of the housing 101. The top of frock board 107 is provided with the slope and puts the position, can place or the individual layer is folded, and a plurality of oil pressure shock absorbers can be placed to a plurality of positions of putting on every layer. The oil pressure shock absorber is placed on the inclined placing position, one end of the piston rod is inclined downwards, and the tail end of the cylinder body is inclined upwards. When the tested oil pressure damper is placed on the inclined placement position, oil of the oil pressure damper completely infiltrates the inner side of the guide sealing part of the oil pressure damper, so that the oil pressure damper with quality problems can be ensured to leak the oil.

A roller slideway taking a box door as a starting point is arranged at the bottom of the inner cavity of the box body 101; the bottom of the tooling plate 107 is provided with a sliding plate matched with the roller slideway; the tooling plate 107 provided with the oil pressure vibration absorber can slide into or out of the box body 101 along the roller slideway; the box body is also provided with a roller slideway outside for receiving the tool plate sliding out of the box body 101, thereby facilitating the loading and unloading of the measured oil pressure vibration damper.

The working principle of the utility model is as follows:

first, the dampers 108 to be measured are placed on the inclined placement positions of the tooling plate 107 in such a manner that one end of the piston rod is inclined downward and the rear end of the cylinder is inclined upward.

Then, the tool plate 107 provided with the tested vibration damper 108 is pushed into the inner cavity of the box body 101 along the roller slideway and fixed; and (3) closing the box door, starting the vacuum pump 102, and opening the evacuation valve to ensure that a pipeline between the vacuum pump 102 and the inner cavity of the box body is smooth. The box body is kept in a vacuum state, after the air pressure outside the tested shock absorber 8 is obviously reduced under the vacuum pumping action, the air pressure inside the tested shock absorber 8 is higher than the air pressure inside the box body 101, the pressure difference forces the oil inside the tested shock absorber 8 to generate a leakage tendency, and if the sealing of the guide sealing part fails, the oil leaks out from the inside of the shock absorber.

Finally, the air pressure in the box body 101 is recovered, the box door is opened, and the tooling plate 107 is pulled out; taking out the tested damper 108 on the tooling plate 107; and visually checking whether oil seeps out from the guide sealing part of the shock absorber 8 one by one, and judging whether the tested shock absorber 108 is qualified. The utility model discloses at test process energy resource consumption few, only just consume the electric energy at vacuum pump 102 during operation, utilize to find time valve 103 pressurize when hardly consuming the electric energy, the energy consumption cost that the event detected is lower.

Claims (9)

1. A device for detecting the sealing performance of an oil pressure shock absorber comprises a box body (101); the method is characterized in that: further comprises a vacuum pump (102) and an evacuation valve (103); the extraction opening of the vacuum pump (102) is connected with the inner cavity of the box body (101) through an evacuation valve (103); in the working process, the inner cavity of the box body is sealed with the external environment; the tank (101) can house an oil damper whose sealing performance is to be detected, and the oil damper is placed in an environment lower than a standard atmospheric pressure.

2. The device for detecting the sealability of an oil pressure shock absorber according to claim 1, wherein: further comprising a tooling plate (107); the tooling plate (107) can be arranged in the box body (101); the top of the tooling plate (107) is provided with an inclined placing position; the inclined placement positions are used for placing the oil pressure shock absorbers, so that the shock absorbers are kept in an inclined state in the detection process.

3. The device for detecting the sealing performance of the oil damper according to claim 2, characterized in that: the box body is provided with a box door; the door can be opened or closed under powered element or manual control.

4. The device for detecting the sealability of an oil pressure shock absorber according to claim 3, wherein: and the box door is sealed with the side opening of the box body through a rubber sealing strip in a closed state.

5. The device for detecting the sealability of an oil pressure shock absorber according to claim 3 or 4, wherein: the bottom of the inner cavity of the box body (101) is provided with a roller slideway taking a box door as a starting point; the bottom of the tooling plate (107) is provided with a sliding plate; the tooling plate (107) can slide into or out of the box (101) along the roller slide.

6. The device for detecting the sealability of an oil pressure shock absorber according to claim 5, wherein: the outer side of the box body (101) is provided with a roller slideway connected to a box door.

7. The device for detecting the sealing performance of the oil hydraulic shock absorber according to claim 3 or 4, wherein: the box door adopts a double-layer or multi-layer structure.

8. The device for detecting the sealability of an oil pressure shock absorber according to claim 1, 2, 3 or 4, wherein: further comprising a pressure sensor (105) and a vacuum gauge (106); the detection ports of the pressure sensor (105) and the vacuum gauge (106) are connected with the inner cavity of the box body (101).

9. The device for detecting the sealability of an oil pressure shock absorber according to claim 1, 2, 3 or 4, wherein: also includes a vacuum breaker (104); and the air outlet of the air breaking valve (104) is connected with the inner cavity of the box body (101).

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