End face sealing liquid leakage rate testing equipment

Abstract

The invention relates to end face sealing liquid leakage rate testing equipment in the field of mechanical sealing, and the end face sealing liquid leakage rate testing equipment consists of a test oil inlet device, a hydraulic control center, a self-design sealing test piece, a tested piece positioning clamp, a pneumatic pressure applying device and a high-precision electronic scale, the measured piece positioning clamp is composed of a profile frame, a positioning clamp and a fixed back plate, and the positioning clamp is fastened on the back plate through a bolt; the pneumatic pressure applying device mainly depends on an electromagnetic valve connecting cylinder to control a telescopic rod to press a sealing test piece so as to meet the required stress requirement, the high-precision electronic scale is used for measuring the weight of the tested piece so as to measure the oil leakage condition of the sealing test piece, and a series of test operations such as cylinder pressure applying and oil conveying are generally controlled by the hydraulic control center in the test process. The invention aims to measure the influence of different sealing end surface appearances on the oil leakage condition of the sealing element.

Description

Technical Field

[0001] This invention relates to the field of mechanical seals, specifically to a device for testing the leakage of liquid from an end face seal. Background Technology

[0002] Oil seals are the "silent guardians" that maintain the normal operation of modern industrial systems. Their applications are extremely wide-ranging, from the engines, transmissions, and wheel hubs of cars we drive every day, to the hydraulic systems of excavators and cranes on construction sites; from the landing gear and engines of airplanes soaring in the sky, to the propellers and steering gears of giant ships sailing the seas; even precision machine tool spindles, household washing machine drums, and demanding petrochemical pumps and valves—almost any situation involving liquid, grease, or gaseous media and accompanied by relatively moving mechanical structures relies on oil seals. Their core significance lies in effectively preventing the leakage of working media and the intrusion of external contaminants, thereby ensuring the reliability, safety, and efficiency of equipment operation. A reliable seal not only significantly reduces energy and material waste, lowers maintenance costs, and extends equipment lifespan, but it is also directly related to production safety and environmental protection—whether it's preventing the leakage of flammable and explosive chemical raw materials, ensuring the hydraulic stability of automotive braking systems, or avoiding soil and water pollution caused by lubricating oil leaks in mechanical equipment, oil seals play an indispensable and crucial role, serving as a solid and unseen cornerstone of modern industrial civilization.

[0003] The morphology and roughness of the sealing end face are the most direct and microscopic key factors determining the sealing performance of oil. Ideally, we want the sealing end face to be an absolutely smooth plane, but in reality, all machined end faces have microscopic peaks (protrusions) and valleys (recesses). These tiny geometric features together constitute the "morphology" of the sealing end face. When two sealing end faces are pressed together under pressure, the actual contact only occurs on these microscopic protrusions, while the recessed grooves form intricate microscopic leakage channels that penetrate the inner and outer diameters. The roughness value is a quantitative representation of the height difference between these microscopic peaks and valleys; the larger the roughness value, the deeper and wider these leakage channels are, and the smaller the resistance encountered by the fluid (oil) as it passes through the end face, resulting in a significant increase in leakage. Conversely, if the roughness value is too low and the surface is too smooth, a lubricating film may not be formed, leading to dry friction, high temperature, and adhesive wear on the end face, which will also compromise the long-term stability of the seal. Therefore, the profound significance of this invention, which considers the influence of the morphology and roughness differences of the sealing end face on oil leakage, lies in the fact that through precise control of this microscopic world, we can directly improve the reliability, safety, and energy efficiency of the entire mechanical system. This means lower downtime risk, longer equipment life, less oil consumption and environmental pollution, ultimately promoting technological progress and safety assurance in high-end equipment from aerospace engines to the automotive industry and even nuclear power plant main pumps. Summary of the Invention

[0004] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a test device for the leakage of liquid from a sealed end face, which solves the problem of measuring the leakage of oil from sealed end faces with different morphologies.

[0005] To achieve the above experimental objectives, the present invention is implemented through the following technical solution:

[0006] A device for testing the leakage of end-face seal liquid includes: a test oil inlet device, a hydraulic control center, a self-designed sealing test piece, a positioning fixture for the oil-absorbing part under test, a pneumatic pressure device, and a high-precision electronic scale. The device is controlled by the hydraulic control center, which uses the pneumatic pressure device to press the sealing test piece. The upper and lower cover plates of the test piece clamp the oil-absorbing part under test. The hydraulic station pumps oil, and finally, the leakage is measured on the high-precision electronic scale.

[0007] The test oil inlet device mainly consists of a test bench body, a hydraulic station, an oil pressure control valve, and oil pipes. A heat dissipation vent is opened on the rear side of the test bench body to prevent the hydraulic station motor from overheating and stopping. One of the two oil pipes is connected to the oil port of the hydraulic station pump, and the other is connected to the oil inlet of the sealing test piece. The two oil pipes are connected by an oil pressure control valve fixed on the outside of the test bench body to ensure the controllability of the pump oil pressure.

[0008] The self-designed sealing test piece mainly consists of two parts: the sealing strip is located on the upper end face of the lower plate. The morphological characteristics and roughness that affect the leakage are studied on the sealing strip. The oil inlet is located on the side of the lower plate. The upper and lower plates are aligned and positioned by the positioning pin holes between the plates. Pressure sensors can also be installed between the two plates to study the effect of different pressure stresses on the oil leakage.

[0009] The pneumatic pressure device mainly consists of a test bench, a positioning base, a cylinder, and a solenoid valve. The base is fixed to the test bench by positioning at the four corners. The cylinder is fastened to the upper cover plate by bolts. The solenoid valve is installed on the rear bracket. A vent pipe is connected between the cylinder and the solenoid valve. The sealing test piece is tightened to the upper end face of the test bench base by bolts.

[0010] The advantage of this invention is that the pressure application device uses pneumatic pressure application. Compared with traditional pressure application methods, pneumatic pressure application is simple and lightweight in structure, has low component cost, is flexible in installation and debugging, and the compressibility of air gives it a natural overload buffering capacity, making it safer to operate.

[0011] The positioning fixture for the test piece is framed by aluminum profiles. The four profiles are fixed together by three fixing plates in pairs. Three support frames are installed between the profiles. The support frames on both sides are tightened with bolts to clamp the test piece's jaws.

[0012] Furthermore, as a preferred option, the material selected for the test piece is a polyurethane-based oil-absorbing material;

[0013] Furthermore, before the test piece is placed on the upper and lower flat end faces of the sealing test piece, a rectangular through hole of the size of the sealing strip is opened in the test piece to ensure that the test piece covers the outer end face of the sealing strip.

[0014] Furthermore, after the oil has been pumped through and the sample has been left to stand, the sample to be tested is placed on a high-precision electronic scale to observe the measured data and determine the leakage amount.

[0015] As a supplement to this invention application, all air pipe connections in this device must be sealed with rubber interfaces to prevent air pressure leakage and reduce measurement errors. Attached Figure Description

[0016] Figure 1 A schematic diagram of the overall structure of the end-face seal liquid leakage testing equipment;

[0017] Figure 2 A schematic diagram of the test oil inlet device for a test equipment for testing the leakage of liquid from an end-face seal.

[0018] Figure 3 A schematic diagram of the hydraulic control center structure for a test device for end-face seal liquid leakage.

[0019] Figure 4 A schematic diagram of the positioning fixture and pneumatic pressure device for a test piece in an end-face sealing liquid leakage testing device;

[0020] Figure 5 A schematic diagram of a self-designed sealing test piece for an end-face sealing liquid leakage testing device;

[0021] Specific labeling in the diagram: 1—Test oil inlet device; 101—Test bench body; 102—Pump hydraulic station; 103—Oil pipe 1; 104—Hydraulic control valve; 105—Oil pipe 2; 2—Hydraulic control center; 201—Main control emergency switch; 202—Hydraulic station start button; 203—Hydraulic station stop button; 204—Solenoid valve air inlet control button; 205—Solenoid valve air outlet control button; 206—Hydraulic gauge; 3—Test piece positioning fixture; 301—Profile bracket; 302—Test piece mounting fixture 303—Profile fixing plate; 304—Profile support frame; 4—Self-designed sealing test piece; 401—Seal upper cover plate; 402—Sealing ring; 403—Lower base of sealing element; 404—Oil inlet of sealing element; 405—Oil guide pipe; 406—End face morphology of sealing ring; 5—Pneumatic pressure device; 501—Two-position two-way solenoid valve; 502—Ventilation pipe 1; 503—Ventilation pipe 2; 504—Cylinder; 505—Pressure device test bench; 506—Positioning base plate; 6—High-precision electronic scale; Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention. Other embodiments obtained by those skilled in the art without inventive effort are all within the scope of protection of this invention.

[0023] Please read the attached document. Figure 1 The overall structure of this invention is as follows: an end-face sealing liquid leakage test device consists of a test oil inlet device 1, a hydraulic control center 2, a test piece positioning fixture 3, a self-designed sealing test piece 4, a pneumatic pressure device, and a high-precision electronic scale 6.

[0024] As attached Figure 2 The structure of the pneumatic pressurization device is as follows: the hydraulic station 102 is installed in the test bench body 101, wherein a strip-shaped heat dissipation hole is opened on the rear side of the test bench body 101 to prevent the hydraulic station from overload and overheating, and a pipe hole is opened on the side of the test bench body 101 to facilitate the connection of the oil pipe between the hydraulic station 102 and the seal 4. One end of the oil pipe 103 is connected to the pump oil port of the hydraulic station 102 and the other end is connected to the oil inlet of the hydraulic control valve 104. One end of the oil pipe 105 is connected to the oil outlet of the hydraulic control valve 104 and the other end is connected to the oil inlet 404 of the seal.

[0025] As attached Figure 3 The hydraulic control center has the following structure: The control panel above the hydraulic control center platform has the following components arranged from left to right: main control emergency switch 201, hydraulic station start button 202, hydraulic station stop button 203, solenoid valve air intake control button 204, solenoid valve exhaust control button 205, and an oil pressure gauge 206 installed in front of the platform to control and detect oil pressure, and also to add reference influencing factors to the experimental process.

[0026] As attached Figure 4 The structure of the test piece positioning fixture and the pneumatic pressure device is as follows: The test piece positioning fixture consists of four aluminum profiles 301 forming a positioning fixture frame fixed on the positioning base plate 506. Three profile fixing plates 303 are bolted to the upper end of the profile frame 301 for stability. Three profile support frames 304 are installed between each pair of profile frames 301. The test piece fixing claw 302 is bolted to the support frames 304 on both sides of the profile frame. The pneumatic pressure device is fixed to the positioning base plate 506 by positioning at the four corners of the test bench 505. The cylinder 504 is installed on the plate on the bench 505. The solenoid valve 501 and the cylinder 504 are connected by the air pipe 502 and the air pipe 503. The pressure effect is achieved on the sealed test piece 4 by the telescopic rod of the cylinder 504 in the pneumatic pressure device.

[0027] The two-way solenoid valve 501 receives air through its inlet port and pressurizes the cylinder 504 through its outlet port via pipe 502. It then discharges pressure from the cylinder 504 outlet port through pipe 503 to the solenoid valve 501 outlet port, using air pressure circulation to achieve the effect of pushing the telescopic rod of cylinder 403 to extend and retract.

[0028] As attached Figure 5 The structure of the gas-designed sealing test piece is as follows: the upper cover plate 401 and the lower base 403 of the sealing piece are aligned and fixed by positioning pins, the sealing strip is located on the upper end face of the lower base 403, and different roughness textures 406 are attached to the sealing ring. The test piece is clamped between the upper cover plate 401 and the lower base 403. A rectangular through hole of the same size as the sealing strip is cut in the middle of the test piece to ensure that the test piece can uniformly absorb the oil in the sealing gap. One end of the oil guide pipe is connected to the oil inlet 404 of the sealing piece and the other end is connected to the oil passage pipe 105.

[0029] In this scheme, when the test starts, after fixing the lower base 403 of the seal, the test piece is laid flat, the upper cover plate 401 of the seal is installed with the positioning pin, and the test piece is clamped by the test piece fixing claw 302. The hydraulic control center 2 controls the cylinder to extend the telescopic rod to press the seal through the solenoid valve air intake control button 204. The hydraulic station start button 202 of the hydraulic control center 2 starts pumping oil. During this period, the hydraulic pressure change on the hydraulic gauge 206 is observed. The pumping time is fixed at 15 minutes. After the end, the oil intake is stopped by the hydraulic station stop button 203, the solenoid valve exhaust control button 205 controls the solenoid valve 501 to exhaust, the telescopic rod of the cylinder 504 retracts, the test piece is taken out, and the value is observed and recorded on the high-precision electronic scale 6. By changing different lower bases of the seal and disposable test pieces, the test process is repeated. The influence of different end face morphologies on the leakage rate is summarized by the recorded data.

[0030] For those skilled in the art, any changes, modifications, substitutions, and variations made to the embodiments without departing from the principles and spirit of the present invention, based on the teachings of the present invention, still fall within the protection scope of the present invention.

Claims

1. A face seal liquid leakage test apparatus, characterized by, The utility model relates to a kind of test oil inlet device (1), for providing controllable hydraulic oil source;Hydraulic control center (2) is used to control the hydraulic and pneumatic system of whole equipment;Self-design sealing test piece (4) is used to install the oil absorption piece measured and form sealing end face;The oil absorption piece positioning fixture (3) is used to fix the oil absorption piece measured;Pneumatic pressing device (5) is used to press the sealing test piece;High-precision electronic scale (6) is used to measure the mass of leakage liquid;Wherein, the hydraulic control center (2) controls pneumatic pressing device (5) to press the self-design sealing test piece (4), test oil inlet device (1) supplies oil to sealing test piece, and leakage liquid is weighed by high-precision electronic scale (6) after being absorbed by the oil absorption piece measured. The test oil inlet device (1) includes a test bench body (101), a hydraulic station (102), an oil pressure control valve (104), and oil pipes (103, 105). The test bench body (101) is provided with a heat dissipation opening at the back side. The hydraulic station (102) is connected with the oil pressure control valve (104) through the oil pipes to control the oil pressure of the pump.

2. The end face seal liquid leakage amount testing apparatus according to claim 1, characterized by, The self-design sealing test piece (4) includes an upper cover plate (401) and a lower base (403), which are aligned and fixed by positioning pins. The lower base (403) is provided with a sealing band on the upper end face. The sealing band has different roughness topographic features (406). The lower base is provided with an oil inlet (404) on the side face.

3. The end face seal liquid leakage amount testing apparatus according to claim 1, characterized by, The self-design sealing test piece (4) is further provided with a pressure sensor for measuring the sealing state under different pressure stresses.

4. The end face seal liquid leakage amount testing apparatus according to claim 3, characterized by, The pneumatic pressing device (5) includes a test bench (505), a positioning base (506), a pneumatic cylinder (504), and a solenoid valve (501). The pneumatic cylinder controls the air pressure through the solenoid valve to push a telescopic rod to apply pressure to the sealing test piece.

5. The end face seal liquid leakage amount testing apparatus according to claim 1, characterized by, The oil absorption piece positioning fixture (3) is composed of an aluminum profile (301) frame, including a profile fixing plate (303), a profile support frame (304), and a measured piece fixing jaw clamp (302) for clamping and positioning the oil absorption piece measured.

6. The end face seal liquid leakage amount testing apparatus according to claim 1, characterized by, The oil absorption piece measured is a polyurethane-based oil absorption material, with a rectangular through hole in the middle matching the size of the sealing band.

7. The end face seal liquid leakage amount testing apparatus according to claim 1 or 6, characterized by All air pipe connection ports in the pneumatic pressing device (5) are provided with rubber sealing interfaces.

8. The end face seal liquid leakage amount testing apparatus according to claim 1, characterized by, The hydraulic control center (2) includes an overall control emergency switch (201), hydraulic station start-stop buttons (202, 203), solenoid valve control buttons (204, 205), and an oil pressure gauge (206).

9. The end face seal liquid leakage amount testing apparatus according to claim 1, characterized by, During the test, the lower base (403) with different sealing band topographies and the oil absorption piece measured are replaced, and the test is repeated to obtain the influence data of different end surface topographies on leakage amount.

10. The end face seal liquid leakage amount testing apparatus according to claim 1, characterized by, ​

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