CN218765987U

CN218765987U - Special tool for accelerated aging test of radial rubber sealing ring

Info

Publication number: CN218765987U
Application number: CN202223047265.6U
Authority: CN
Inventors: 张春梅; 杜明欣; 牛鑫培; 王荣荣; 崔俞; 杜华太; 杨敬亭; 刘坤; 刘学通; 景玉龙; 王炎; 张斌; 张志刚
Original assignee: Shandong Non Metallic Material Research Institute
Current assignee: Shandong Non Metallic Material Research Institute
Priority date: 2022-11-16
Filing date: 2022-11-16
Publication date: 2023-03-28
Anticipated expiration: 2032-11-16

Abstract

The utility model discloses a special frock of radial rubber seal accelerated aging test belongs to rubber seal test technical field. The utility model discloses a special frock is including experimental frock and sample frock. The test tool can acquire the compression permanent deformation performance data and deduce the aging life of the batch seal ring aging test, thereby shortening the test time and improving the test efficiency; the perpendicularity of the middle shaft and the upper surface in the process of taking out the metal shaft can be guaranteed through the sampling tool, the damage to the sealing ring caused by collision of the tool due to eccentricity is avoided, the sampling efficiency can be improved, the recovery time for taking out a sample of the sealing ring is guaranteed to meet the standard requirement, and therefore the reliability of aging test data is guaranteed.

Description

Special tool for accelerated aging test of radial rubber sealing ring

Technical Field

The utility model belongs to the technical field of the rubber seal test, concretely relates to radial rubber seal compression aging test special frock with higher speed.

Background

According to the size of the groove of the O-shaped ring for hydraulic and pneumatic air of GB/T3452.3, the rubber sealing ring is divided into radial sealing and axial sealing according to the using state.

The compression ratio and the groove filling rate of main design parameters of the sealing ring during radial sealing are greatly different from those of axial sealing. In the process of using and storing the rubber sealing ring for static sealing, the performance of the rubber sealing ring for static sealing can be aged along with the increase of time, and even the service performance is lost. The accelerated aging test of the sealing ring is to calculate the performance of the sealing ring after long-term storage at room temperature by constructing a relationship between performance change and temperature-time, and judge the storage life of the sealing ring through critical examination. The rubber sealing ring is in a compression state in actual use, and the compression permanent deformation can better reflect the service performance of the sealing ring. In the estimation of the aging life of the rubber sealing material, the compression set is mostly selected as a performance change index, and a curve of the compression set changing with time is obtained through an accelerated aging test at a higher temperature, so that the service life of the sealing ring is calculated.

At present, the test process of predicting the aging life of the radial seal ring mainly adopts an actual sample piece for testing, and the accelerated aging test process generally comprises the following steps: determining test temperature, determining sampling time interval period, measuring initial performance, carrying out compression set performance data acquisition, processing data, calculating aging coefficient, calculating compression set under room temperature long-term storage and performing critical assessment. The process which consumes most time and manpower and material resources is a compression permanent deformation measuring process at different temperatures. The collection sample size of the compression set data is large, the number of sampling points is large, the workload of tool disassembly and installation is huge, and even the reliability of the test data is reduced because the parking time after the sample is taken out exceeds the standard requirement and certain test points of the compression set rate deviate from a rule curve, so that the confidence coefficient of the service life calculation result is low.

For some sample pieces which are difficult to disassemble or large in size and difficult to test in batches, a test tool needs to be designed for collecting the compression permanent deformation performance.

Patent 201910375804.2 discloses a rubber compression permanent deformation device with adjustable compression height, which utilizes the rotation of a threaded rod with forward and reverse threads at two ends to realize the approaching or separating of limiters at two sides, and further enables the compression height of a tested sample to be adjusted according to actual needs through the change of the vertical distance of an upper compression plate and a lower compression plate. Patent 201820928147.0 discloses a compression set clamp for rubber, which is also a test fixture for measuring compression set against axial compression. The common characteristics of these frocks are axial compression, and the adjustment of the compression ratio is realized by adjusting the height of the limiting block. When the compression permanent deformation is actually adopted to construct the relation of performance change-temperature-time, the relation of compression ratio-temperature-time is different when the sealing ring is compressed axially and radially. A radial seal test tool which can better reflect the use state of the radial seal rubber ring is adopted for carrying out an accelerated aging test. At present, no compression permanent deformation test tool designed for a radial seal aging test exists.

Disclosure of Invention

The utility model aims to solve the technical problem that a radial rubber seal ring accelerated aging test special frock is provided.

In order to solve the technical problem, the utility model discloses to the aging test of radial seal circle, for causing the damage in avoiding experimental, designed dedicated experimental frock and sample frock, can portably carry out batch seal circle aging test compression permanent deformation performance data acquisition and ageing life-span derivation high-efficiently to realize the purpose of the invention.

The utility model relates to a special tool for accelerated aging test of radial rubber sealing ring, which comprises a test tool and a sampling tool; the testing tool is used for providing compression deformation for the radial rubber sealing ring, and the shape, the structure and the size of the testing tool depend on the specification and the size of the radial rubber sealing ring to be tested; the sampling tool comprises a force application device, a movable device, a connecting mechanism and a fixing device, and is used for opening the test tool under the condition that the radial rubber sealing ring is not damaged, so that the sealing ring can be conveniently taken out; two sets of connecting mechanisms are symmetrically arranged; the force application device applies force to the movable device by means of the connecting mechanism to enable the movable device to move in the vertical direction; the fixing device of the sampling tool is fixed at the front end of the bottom of the movable device.

Preferably, the test tool comprises a tool plate and a sealing shaft; the tooling plate is provided with a step hole matched with the specification and the size of the radial rubber sealing ring along the thickness direction and is composed of an upper cylindrical hole and a lower cylindrical hole which are coaxial; the sealing shaft consists of an insertion head and a step shaft, and the step shaft consists of an upper cylinder and a lower cylinder which are coaxial and are respectively matched with the two coaxial cylindrical holes of the step hole; the fixing device of the sampling tool is used for fixing the plug head.

Preferably, the force application device comprises a rocker, a support mechanism and a crank, wherein the front end of the rocker is connected with the crank, and the support mechanism is arranged below the rocker and used for providing fulcrum support for the rotation of the rocker; the movable device comprises an outer cylinder and a sliding inner cylinder which are connected in a sleeved mode, and the front ends of the bottoms of the outer cylinder and the sliding inner cylinder are provided with notches so as to avoid interference on the movement of the fixing device along the vertical direction; the connecting mechanism is used for connecting the crank and the sliding inner cylinder; the fixing device is an angle fork, and the front end of the fixing device is provided with an opening.

Preferably, the connecting mechanism comprises a fixed shaft, a cross rod positioning hole, a cross rod hanging ring and a cross rod; the fixed shaft is fixedly connected with the crank; the cross rod positioning hole is a through hole formed in the wall of the outer barrel; the cross rod is fixed on the outer wall of the sliding inner cylinder; the cross rod is placed in the cross rod positioning hole in a mode of moving up and down, and the upper end and the lower end of the cross rod lifting ring are respectively connected with the fixed shaft and the cross rod.

Preferably, the cross rod hanging ring is of a rigid structure, and the upper end and the lower end of the cross rod hanging ring are fixedly connected with the fixed shaft and the cross rod respectively.

Further preferably, the supporting mechanism is composed of a rocker positioning shaft and a fixing support, the rocker positioning shaft is fixed on the rocker, a round hole is formed in the top end of the fixing support, the bottom end of the fixing support is fixed on the outer wall of the outer barrel, and the rocker positioning shaft is arranged in the round hole of the fixing support in a rotatable mode.

The utility model discloses a radial rubber seal ring aging test's special frock is including experimental frock and sample frock. The test tool can acquire compression permanent deformation performance data and deduce aging life of the batch seal ring aging test, so that test time is shortened, and test efficiency is improved; the sampling tool can guarantee the verticality of the middle shaft and the upper surface in the process of taking out the metal shaft, avoids the damage to the sealing ring caused by collision of the tool due to eccentricity, can improve the sampling efficiency, and guarantees that the recovery time of taking out a sample of the sealing ring meets the standard requirement, thereby ensuring the reliability of aging test data.

Drawings

FIG. 1 is a schematic structural view of a multi-specification radial sealing rubber ring aging test tool;

FIG. 2 isbase:Sub>A sectional view taken along line A-A of FIG. 1;

FIG. 3 is a sectional view taken along line B-B of FIG. 1;

FIG. 4 is a schematic view of a stepped bore configuration;

FIG. 5 is a schematic view of a stepped shaft structure;

FIG. 6 is a schematic view showing a positional relationship among a seal ring, a seal shaft, and a stepped hole in an aging test;

fig. 7 is a schematic structural view of a sampling tool.

The device comprises a tooling plate 1, a step hole 101, a sealing shaft 2, an inserting and pulling head 21, a step shaft 22, a rocker 3, a rocker positioning shaft 4, a crank 5, a fixed shaft 6, a cross rod positioning hole 7, a cross rod lifting ring 8, a cross rod 9, an outer cylinder 10, a sliding inner cylinder 11 and an angle fork 12.

Detailed Description

The present invention will be further described with reference to the following examples and drawings, but the present invention is not limited thereto.

Example one

The sealing ring of this embodiment is a nitrile rubber series sealing ring for a certain type of pressure reducing valve, and the sealing ring cross-section is O shape, and includes three sealing rings, and its specification is respectively phi 18.5mm × 2.5mm, phi 7.7mm × 2.5mm and phi 6.7mm × 1.9mm, and the sealing form of sealing ring is radial seal.

This embodiment series of sealing washer is ageing test special fixture with higher speed, including experimental frock and sample frock.

The test tool comprises a tool plate 1 and a sealing shaft 2; three specifications of through step holes 101 are formed in the tooling plate 1 along the thickness direction, the upper parts of the step holes 101 are cylindrical holes with the height D and the diameter phi B, and the lower parts of the step holes are concentric cylindrical holes with the height E and the diameter phi A; the upper edge of the upper cylindrical hole is provided with a chamfer F. The sealing shaft 2 consists of an inserting and pulling head 21 and a step shaft 22, the upper part of the step shaft 22 is a cylindrical shaft with the diameter phi B, the lower part of the step shaft 22 is a concentric cylindrical shaft with the height C and the diameter phi A, and the edge of the bottom surface of the lower cylindrical shaft is provided with a chamfer; the sealing shaft 2 has three specifications and is matched with the stepped holes 101 of the three specifications respectively. The difference between the height C of the cylindrical shaft below the seal shaft 2 and the height E of the cylindrical hole below the stepped hole 101 is the seal groove, as shown in fig. 1-6. Referring to the design standard of GB/T3452.3, the dimensions of the stepped hole 101 and the matched stepped shaft 22 are detailed in Table 1.

The sampling tool is a rocker sliding mechanism and comprises a rocker 3, a rocker positioning shaft 4, a supporting bracket, a crank 5, a fixed shaft 6, a cross rod positioning hole 7, a cross rod hanging ring 8, a cross rod 9, an outer barrel 10, a sliding inner barrel 11 and an angle fork 12, as shown in fig. 7. The support bracket comprises a vertical cylinder and two transverse cylinders, the rear ends of the two transverse cylinders are fixed below the vertical cylinder, and a through hole is formed in the top end of the vertical cylinder. A cross bar hanging ring 8 which is a belt. The outer cylinder 10 is of a cylindrical structure, a semi-cylindrical gap is formed in the cylinder wall at the front end of the lower portion of the outer cylinder, and the left and right side cylinder walls are provided with a cross rod positioning hole 7 and a long circular through hole structure which are communicated with each other. The sliding inner cylinder 11 is of a cylinder structure, a semi-cylindrical notch is arranged on the cylinder wall at the front end below the sliding inner cylinder, a cylindrical cross rod 9 is arranged in the cylinder along the radial direction, and two ends of the cylindrical cross rod extend out of two sides of the cylinder wall. The angle fork 12 is of U-shaped structure. The front end of a rocker 3 of the sampling tool is connected with a crank 5, and a rocker positioning shaft 4 is arranged at the joint of the crank and the crank; the through hole at the upper end of the supporting bracket is rotatably connected with the rocker positioning shaft 4, and the two transverse cylinders at the lower part are fixed on the outer wall surface at the rear end of the outer barrel 10; the angle fork 12 is positioned in the inner cavity of the sliding inner cylinder 11, is fixed on the inner wall surface of the bottom end of the cylinder wall at the rear part of the sliding inner cylinder 11, and has two branches facing forwards; the sliding inner cylinder 11 is sleeved in the inner cavity of the outer cylinder 10, and the extending tail ends of the two cross rods 9 are respectively positioned in the cross rod positioning holes 7; the top end of the cross rod hanging ring 8 is connected with the fixed shaft 6, and the bottom end of the cross rod hanging ring is connected with the middle position of the cross rod 9.

TABLE 1 size of aging test tool for multi-specification radial sealing rubber ring

When the special tool of the embodiment is used for carrying out an aging test on the radial sealing nitrile rubber O-shaped ring according to the GB/T92.1 method, the specific steps are as follows:

1. and determining the aging test temperature and the sampling period according to the type of the rubber material, wherein 5 test temperatures are selected, namely 70 ℃, 80 ℃, 90 ℃, 100 ℃ and 110 ℃, so that 5 sets of corresponding test tools are needed, and only one set of sampling tool is needed.

2. The radial section size of the sealing ring is measured by a caliper or an optical measuring instrument, and the specification of the sealing ring and the batch of the sealing ring which are matched with the tooling plate 1 and the sealing shaft 2 are numbered for avoiding confusion because of large sample size.

3. In order to facilitate the installation, lubricating grease is coated on the outer wall surface below the sealing shaft 2, and then the matched rubber sealing ring is sleeved into the sealing shaft 2 from the lower part to the sealing groove. And finally, the sealing shaft 2 provided with the sealing ring is arranged in the corresponding stepped hole 101 from top to bottom, and the position of the sealing ring is shown in fig. 7. The same procedure is used to install all the seals.

4. And (4) placing the test tools with different aging temperatures into an aging box for aging, and taking out the test tools when a specified sampling period is reached.

5. And (3) placing the angle fork 12 of the sampling tool below the plug head 21 of the sealing shaft 2, pressing the rocker 3 downwards, driving the crank 5, the sliding inner cylinder 11 and the angle fork 12 to move upwards, finally taking the sealing shaft 2 out of the step hole 101, recovering for 30min, and measuring the cross section size of the sealing ring. And testing the compression set of the sealing ring after meeting the requirement of the parking time according to an aging scheme established by referring to a GB/T7759.1 test method, and calculating the compression set rate at each temperature.

6. And (5) repeating the steps 3-5 until all compression set rate data of all the sealing rings at different temperatures in all sampling periods are obtained.

7. According to the GB/T92.2 statistical method, the compression permanent deformation retention rate performance-time relation at a certain aging temperature is supposed to accord with P = Ae-Kt ^α And (3) a model, after taking logarithm of the model, establishing a rubber aging characteristic equation Y = a + bX, and solving a performance change rate constant and a linear correlation coefficient by a least square method. In the test, the phi is 18.5mm multiplied by 2.5mm under each test temperaturea、b、rAnd rate constant of change of propertiesKSee table 2.

TABLE 2 compressibility of 25% at the respective test temperaturesa、b、rAnd rate constant of change of performanceK

As shown in Table 2, the confidence is 99%, r > r, and the compression ratio is 25%, X and Y are in linear relation, assuming that the model is true.

In the same way, the sealing rings with other two specifications can be solved at each test temperaturea、b、rAnd rate constant of change of performanceK。

8. The performance change rate constants and the temperature reciprocals at different temperatures accord with Gibbs free energy functions, logarithms are taken from the formula, related parameters are solved by adopting a least square method, the linear correlation of the two parameters at a certain confidence coefficient is judged, and if the linear correlation is obtained, the performance change rate constants and the upper limit value of the performance change rate constants at normal temperature or storage temperature are calculated.

9. Critical assessment: respectively calculating the time required to be aged at the high temperature and the corresponding aging time of the lower limit value of the performance when the glass is stored at normal temperature for 12 years, 16 years and 21 years or the required service life is X years. And (4) assembling the rubber sealing ring in the tool, aging according to corresponding time, finishing at fixed time, and performing critical examination. If the examination is passed, the sealing ring can be stored for X years at normal temperature.

Example two

The sampling tool of the embodiment is a rocker sliding mechanism, and comprises a rocker 3, a rocker positioning shaft 4, a support bracket, a crank 5, a fixed shaft 6, a cross rod positioning hole 7, a cross rod hanging ring 8, a cross rod 9, an outer cylinder 10, a sliding inner cylinder 11 and an angle fork 12, as shown in fig. 7. The supporting bracket consists of a vertical cylinder and two transverse cylinders, the rear ends of the two transverse cylinders are fixed below the vertical cylinder, and the top end of the vertical cylinder is provided with a through hole. And the cross bar hanging ring 8 is made of stainless steel. The outer cylinder 10 is of a regular hexagon cylindrical structure, the wall surface of the most front cylinder is provided with a notch from bottom to top, and the left and right side cylinder walls are provided with a cross rod positioning hole 7 and a long circular through hole structure which are communicated with each other. The sliding inner barrel 11 is of a regular hexagon tubular structure, a notch is arranged on the barrel wall surface at the forefront from bottom to top, and two cylindrical cross rods 9 are symmetrically arranged on the outer side of the barrel wall. The angle fork 12, a C-shaped structure, with the opening facing forward.

The front end of a rocker 3 of the sampling tool is connected with a crank 5, and a rocker positioning shaft 4 is arranged at the joint of the crank and the rocker 3; the through hole at the upper end of the support bracket is rotatably connected with the rocker positioning shaft 4, and the two transverse cylinders at the lower part are fixed on the outer wall surface at the rear end of the outer cylinder 10; the angle fork 12 is positioned in the inner cavity of the sliding inner cylinder 11 and is fixed on the inner wall surface at the bottom end of the rear cylinder wall of the sliding inner cylinder 11; the sliding inner cylinder 11 is sleeved in the inner cavity of the outer cylinder 10, and the two cross rods 9 respectively extend out of the cross rod positioning holes 7 on the two sides; and two cross bar hoisting rings 8 are respectively connected with a cross bar 9 positioned on the same side and a fixed shaft 6 fixed on the crank 5.

The sample frock of this embodiment, its horizontal pole rings 8 are rigid structure, and after accomplishing the sample, can resume below position with angle fork 12 through removing rocker 3, make things convenient for next use.

Claims

1. The utility model provides a special frock of radial rubber seal accelerated ageing tests, includes experimental frock and sample frock, its characterized in that: the testing tool is used for providing compression deformation for the radial rubber sealing ring, and the shape, the structure and the size of the testing tool depend on the specification and the size of the radial rubber sealing ring to be tested; the sampling tool comprises a force application device, a movable device, a connecting mechanism and a fixing device, and is used for opening the test tool under the condition that the radial rubber sealing ring is not damaged, so that the sealing ring can be conveniently taken out; two sets of connecting mechanisms are symmetrically arranged; the force application device applies force to the movable device by means of the connecting mechanism so as to enable the movable device to move in the vertical direction; the fixing device of the sampling tool is fixed at the front end of the bottom of the movable device.

2. The special tool for the accelerated aging test of the radial rubber sealing ring according to claim 1, characterized in that: the test tool comprises a tool plate (1) and a seal shaft (2); the tool plate (1) is provided with a step hole (101) matched with the radial rubber sealing ring in specification and size along the thickness direction and is composed of an upper cylindrical hole and a lower cylindrical hole which are coaxial; the sealing shaft (2) is composed of an insertion head (21) and a step shaft (22), the step shaft (22) is composed of an upper cylinder and a lower cylinder which are coaxial, and the upper cylinder and the lower cylinder are respectively matched with two coaxial cylindrical holes of the step hole (101); the fixing device of the sampling tool is used for fixing the plug head (21).

3. The special tool for the accelerated aging test of the radial rubber sealing ring according to claim 1, characterized in that: the force application device comprises a rocker (3), a supporting mechanism and a crank (5), the front end of the rocker (3) is connected with the crank (5), and the supporting mechanism is arranged below the rocker (3) and used for providing fulcrum support for the rotation of the rocker (3); the movable device comprises an outer cylinder (10) and a sliding inner cylinder (11) which are connected in a sleeved mode, and the front ends of the bottoms of the outer cylinder and the sliding inner cylinder are provided with notches so as to avoid interference on the movement of the fixing device in the vertical direction; the connecting mechanism is used for connecting the crank (5) and the sliding inner cylinder (11); the fixing device is an angle fork (12), and the front end is provided with an opening.

4. The special tool for the accelerated aging test of the radial rubber sealing ring according to claim 3, characterized in that: the connecting mechanism comprises a fixed shaft (6), a cross rod positioning hole (7), a cross rod hanging ring (8) and a cross rod (9); the fixed shaft (6) is fixedly connected with the crank (5); the cross rod positioning hole (7) is a through hole formed in the wall of the outer barrel (10); the cross rod (9) is fixed on the outer wall of the sliding inner cylinder (11); the cross rod (9) is placed in the cross rod positioning hole (7) in a mode of moving up and down, and the upper end and the lower end of the cross rod hanging ring (8) are respectively connected with the fixed shaft (6) and the cross rod (9).

5. The special tool for the accelerated aging test of the radial rubber sealing ring according to claim 4, characterized in that: the cross rod hoisting ring (8) is of a rigid structure, and the upper end and the lower end of the cross rod hoisting ring are respectively and fixedly connected with the fixed shaft (6) and the cross rod (9).

6. The special tool for the accelerated aging test of the radial rubber sealing ring according to claim 3, characterized in that: the supporting mechanism is composed of a rocker positioning shaft (4) and a fixing support, the rocker positioning shaft (4) is fixed on a rocker (3), a round hole is formed in the top end of the fixing support, the bottom end of the fixing support is fixed on the outer wall of an outer barrel (10), and the rocker positioning shaft (4) is arranged in the round hole of the fixing support in a rotatable mode.