HG/T 3612-1999 Rubber seals for automotive hydraulic disc brake cylinders
Some standard content:
ICS83.140.50
Chemical Industry Standard of the People's Republic of China
HG/T 3088—1999
HG/T3612—1999
Rubber sealing strips and sealing rings for automobiles
Published on April 20, 1999
Implementation on April 1, 2000
Published by the State Administration of Petroleum and Chemical Industry
Registration No.: 2815—1999
HG/T 3612—1999
This standard is not equivalent to the Japanese Industrial Standard JIS D2609-93 "Rubber sealing rings for automotive disc brake cylinders for non-petroleum-based brake fluids".
The main difference between this standard and JISD2609 is that because it is basically a pure rubber product, some repeated contents in the physical performance requirements of vulcanized rubber and the physical performance requirements of seals, such as hardness, hot air aging, and liquid resistance, are only required in the physical performance requirements of vulcanized rubber, and omitted in the physical performance requirements of seals:
The "storage corrosion" requirement and its test method in the physical performance requirements of seals are deleted; inspection rules, marking, packaging, transportation and storage regulations are added. Appendix A of this standard is the standard appendix.
Appendix B of this standard is the reminder appendix.
This standard was proposed by the Technical Supervision Department of the former Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Sealing Products Sub-Technical Committee of the National Technical Committee for Standardization of Rubber and Rubber Products. The drafting units of this standard are: Northwest Rubber and Plastic Research and Design Institute of the Ministry of Chemical Industry, Guizhou Dazhong Image Rubber Co., Ltd., and Tieling Rubber Seals Factory.
The main drafters of this standard are: Hao Fusen, Wang Jingmin, Gao Jingru, and Li Zhongshe. Chemical Industry Standard of the People's Republic of China
Rubber seals used for automobile hydraulic disc brake cylinders1 Scope
HG/T3612-1999
This standard specifies the classification, requirements, test methods, inspection rules and marking, packaging, transportation and storage of rubber seals used for automobile disc brake cylinders using non-petroleum-based brake fluid (hereinafter referred to as seals). This standard applies to rubber seals used for automobile disc brake cylinders using non-petroleum-based brake fluid. 2 Referenced Standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. G/T528—1998 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber (eqYISO37:1994) GB/T531—1999 Rubber pocket hardness test method for indentation hardness (idtISO76191986) GB/T1690—92 Test method for liquid resistance of vulcanized rubber (neqISO1817:1985) GB/T2828—87 Batch inspection counting sampling procedure and sampling table (applicable to inspection of continuous batches) GB 2941-91 Standard temperature, humidity and time for environmental conditioning and testing of rubber specimens (eqvISO471:1983) GB/T3512-83 (89) Rubber hot air aging test method (neqIS01881976) GB/T5721-93 General provisions for marking, packaging, transportation and storage of rubber sealing products GB/T5723-93 Determination of dimensions of specimens and products for testing vulcanized rubber or thermoplastic rubber (eqvISO4648:1991) CB/T6031-199 8 Determination of hardness of vulcanized rubber or thermoplastic rubber (10~100IRHD) (idtISO48:1994) GB/T7535-96 Classification of vulcanized rubber Classification system description (eqvISO4632.1:1982) GB/T7759-1996 Determination of compression set of vulcanized rubber and thermoplastic rubber at room temperature, high temperature and low temperature (egvIS0815-1991)
Vulcanized rubber or thermoplastic rubber Samples and test specimens Part 1: Physical tests GB/T9865.1 -:1996
(idtISO46611：1993)
GB10830—89 Technical conditions for the use of automotive brake fluid 3 Classification
The sealing ring materials specified in this standard are divided into two categories, A and B, according to the use temperature: Class A materials are used under normal working temperature conditions, with a maximum use temperature of 120°C; Class B materials are used under high temperature working conditions, with a maximum use temperature of 150°C. 4 Requirements
4.1 Materials and processes
All raw materials and manufacturing processes shall comply with the requirements of relevant technical specifications. Approved by the State Administration of Petroleum and Chemical Industry on April 20, 1999 and implemented on April 1, 2000
Www.bzsOso.cOm4.2 The physical properties of vulcanized rubber are shown in Table 1. 4.3 The physical properties of the sealing group are shown in Table 2. HG/T3612--1999
Table 1 Physical property requirements of vulcanized rubber
Hardness, IRHB or Buer A, degree
Tensile strength, minimum, MPa
Elongation at break, minimum, %
Compression set, Type B specimen
Class A 120℃×24 h
Class B 150UX24h
Hot air aging
Class A 120X72h
Class B 13×72 h
Change of hardness IRHD or part A, degree
Change of tensile strength, maximum, %
Change of elongation at break, maximum, %
State after aging
Liquid resistance
Class A 120℃x70h
Class B 150℃X70h
Change of hardness, IRHD Or Shore A, degree
Tensile strength change rate, maximum, %
Elongation change rate, maximum, head
Volume change, device
Post-test state
70±5 or 75±5
No abnormal appearance such as electric charge, shape, gas, etc. is allowed-15～0
No abnormal appearance such as turtle, shape, gas pool, stickiness and carbon black precipitation is allowed
Table 2 Physical performance requirements of sealing ring
120CX70H
Class B 150C×70h
Precipitation volume ratio, maximum, %
Metal corrosion
100C X120 h
Mass change of tin iron sheet, maximum, mg/cm*Mass change of steel plate, maximum, mg/cm
Mass change of aluminum sheet, maximum, nug/cm
Mass change of group sheet, maximum, mg/cm2
Mass change of copper sheet, maximum, mg/cm2
Mass change of copper sheet, maximum, mg/cm*
Mass change of zinc sheet, maximum, ag/cm
Change of metal test piece
Appearance of sealing tunnel
Health, 4
No visible corrosion caused by wetness or surface roughness is allowed, but discoloration is allowed
No significant change is allowed in shape and surface stateW Serial number
Plug resistance
40℃×22 h
Low temperature bending test
Low temperature sealing
40℃x120h
Normal working durability
Temperature 4 ~ 35 C
Gain pressure (7±0.3)MPa
Frequency (17±1)min 1
Working times 5×10%
Commercial temperature working durability
Class A mixing
120Cx70 h
Class B overflow 150℃×70h
Sugar pressure (7heart3)MPa
Frequency (17±1)min-1
Working times 5× 105
4.4 Appearance quality
HG/T3612—1999
Table 2 (end)
No cracks are allowed, and the original state should be basically restored within 1 min. No leakage is allowed
1) During the test, no pressure drop due to leakage of the sealing group is allowed; 2) No leakage from the sealing opening is allowed
3) The sealing pattern should be free of harmful deformation, wear and other defects; 4) The piston and the inside of the cylinder that contacts the sealing ring and its surrounding parts are not allowed to have visible corrosion; but slight stains or discoloration are allowed. 1) During the test, no pressure drop due to leakage of the sealing ring is allowed; 2) No leakage from the sealing ring is allowed; 3) The sealing ring should be free of harmful deformation,Wear and other defects 14) The parts of the piston and cylinder that are in contact with the seal ring and the parts near it shall not have visible corrosion: but slight stains or discoloration are allowed. The surface of the seal ring should be well processed and should be free of harmful bubbles, cracks, burrs, foreign matter, etc. 4.5 Dimensions and dimensional tolerances
The dimensions and dimensional tolerances of the seal ring shall comply with the requirements of the drawings. 5 Test methods
5.1 Sample preparation and environmental adjustment
5.1.1 The sample shall be prepared in accordance with GB/T 9865. 1. 5.1.2 The sample environment shall be adjusted in accordance with GB 2941. 5.1.3 The brake fluid used in the test shall be the JG3 brake fluid required in GB10830 or the brake fluid agreed upon by the supplier and the buyer. 5.2 Physical property test of vulcanized rubber
5.2.1 Hardness shall be tested in accordance with GB/T531 and GB/T6031. The method specified in GB/T6031 is the arbitration method. 5.2.2 The tensile strength and elongation at break shall be tested in accordance with GB/T528, and 5.2.3 The compression set shall be tested in accordance with GB/T7759. 5.2.4 The hot air aging shall be tested in accordance with GB/T3512. 5.2.5 The liquid resistance shall be tested in accordance with GB/T1690. 5.3 Physical property test of sealing diagram
WHG/T 3612—1999
5.3.1 The precipitation shall be tested in accordance with A1 in Appendix A. 5.3.2 The metal corrosion shall be tested in accordance with A2 in Appendix A. 5.3.3 The plugging resistance shall be tested in accordance with A3 in Appendix A. 5.3.4 The low temperature sealing shall be tested in accordance with A4 in Appendix A: 5.3.5 The normal temperature working durability shall be tested in accordance with A5 in Appendix A. 5.3.6 The durability of high temperature operation shall be tested in accordance with the provisions of A6 in Appendix A. 5.3.7 The appearance quality of the seal shall be checked visually or with a measuring tool with an accuracy of 0.02 mm. 5.3.8 The size of the sealing ring shall be measured with a measuring tool with an accuracy of 0.02 mm. 6 Inspection rules
6.1 Rubber
6.1.1 The same type of rubber produced by the same shift and the same machine is a batch. 6.1.2 Hardness, tensile strength and elongation at break tests shall be carried out batch by batch. Compression permanent deformation test, hot air aging test and liquid resistance test shall be carried out at least once a month.
6-1.3 When the inspection result is unqualified, double samples shall be taken for re-inspection of the unqualified items. If the re-inspection is unqualified, the rubber is allowed to be refined once. After refining, all performance tests must be carried out. If one of them is still unqualified, the batch of rubber is unqualified. 6.2 Sealing rings
6.2.1 Sealing rings of the same specification shall be batched in batches of no more than 10,000 pieces. 6.2.2 The appearance quality of the products shall be inspected piece by piece. 6.2.3 The dimensions of the products shall be sampled in accordance with GB/T2828, and the inspection level S-2 qualified quality level (AQL) shall be 4.0. 6.2.4 Cold resistance test, precipitation test and metal corrosion test shall be conducted at least once every quarter. If the test results are unqualified, the unqualified items shall be re-tested. If one sealing ring is still unqualified after the re-test, the batch of products shall be unqualified. 6.3 Type inspection
When any of the following situations occurs, all items specified in this standard shall be subject to type inspection: When a new product is finalized or the product is transferred to another factory for production: "After formal production, if there are major changes in materials and processes that may affect product performance: When there is a significant difference between the factory inspection results and the previous type inspection results: - When the national quality supervision agency proposes a type inspection requirement; - When it is used to match a new model.
7 Marking, packaging, transportation and storage
Marking, packaging, transportation and storage shall be carried out in accordance with the provisions of GB/T5721. If there are special requirements, they shall be resolved through consultation between the supply and demand parties.A1 Sedimentation test
A1. 1 Test device
HG/T 3612-1999
Appendix A
(Appendix to the standard)
Test method for physical properties of sealed ketone
a) Sample bottle: volume of about 350ml, wide-mouth frosted stopper colorless glass bottle, bottom diameter 70~80mm (or the test device shown in Appendix B Figure B1).
b) Conical scale high-center test tube: volume 20ml, tube mouth diameter 20~24mm, length 100~120mm. c) Electric centrifuge: can continuously adjust the speed, and can make the centrifuge tube reach 600~700 times the gravity acceleration at the center of gravity. The centrifuge speed can be determined according to formula (A1):
N30 /n/r
Where: N-centrifuge speed, r/min
Pregnancy—gravitational acceleration multiple:
The vertical distance from the center of gravity of a centrifuge tube to the center line of the rotating shaft. III. Example n=659 r=0. 15 m Then: N=2000 r/min(A1)
d) Oven: Electric blast constant temperature drying oven. The oven temperature can be adjusted according to the test method requirements [Class A sample (1.20±2)C: Class B sample (150±2)1.
A1.2 Sample
Take any two sealing rings from the sample, cut two roughly identical whole sections according to the central angle, as a group of samples, with a total weight of (4±0.2). Take two groups of samples in total. Clean with 95% ethanol. A1.3 Test steps
Take three sample bottles, add 75ml of brake fluid to each, put a group of samples in each of the two sample bottles, and use the other for a blank test. Cover the bottle stoppers tightly and put them in an oven that has been adjusted to the specified temperature [Class A (120±2)C, Class B (150±2)℃. After (70±1)h, take out the sample bottles from the oven and cool them at room temperature for 24 h. For each sample bottle, clamp the sample with a forge, shake it thoroughly, then take out the sample, shake the brake fluid in the sample bottle, and immediately inject it into a centrifuge test tube to the 20ml mark, put it into the centrifuge, start the centrifuge, and reach the specified speed. After 10 minutes, stop the machine and let the centrifuge stop by inertia. Take out the centrifuge test tube and read the sediment volume value. Put it in the centrifuge and rotate it for 10 minutes again to check whether there is any difference in the sediment volume before and after. If there is a difference, it should be placed in the machine for another 10 minutes, and the sediment volume at the end of the drink is used as the reading value. Perform two groups of sample tests and blank tests at the same time. Calculate the sediment volume ratio of each group of samples, and take the arithmetic mean of the sediment volume ratios of the two groups of samples as the test result.
A1.4 The sediment volume ratio is calculated according to formula (A2): Sediment volume ratio (%) = (V,-V2)/20×100% In the formula; V,---the sediment volume of the sample test, ml, V--the sediment volume of the blank test, ml.
A2 Metal glass corrosion test
A2.1 Test equipment
a) Analytical balance, weighing accuracy 0.1 mg: (A2)
b) Sample bottle: wide-mouth frosted stopper colorless glass bottle with a volume of 350~400ml and a bottom diameter of 70~80mm (see Appendix B Figure B2)
HG/T3612—1999
c) Oven: electric heating blast constant temperature drying oven. The temperature is adjusted to (100±2)℃. A2.2 Samples
a) Sealing ring: take two sealing ring samples at random, and clean them with 95% ethanol. b) Metal test pieces: two groups, the variety, brand and size of each dimension are shown in Table A1 and Figure A1. Table A1 Gold-filled test piece
Key iron sheet
YB314-64
0. 3~- 0. 5
LY12-CZ
HT20-40
A2.3 Test method
Take two groups of sealing rings and metal test pieces for parallel tests. For each metal test piece (except the plated pot iron sheet), use 200 sandpaper to wipe off the scratches and pits on the surface of the test piece, and then polish it with 00 sandpaper. Each type of gold test piece should use a new piece of sandpaper. Then use cotton wool to fumigate 95% ethanol to decontaminate all metal test pieces, and then wipe them with clean cotton wool until the cotton wool is no longer contaminated. The polished metal test piece should be clamped with a clean forge to prevent finger contact. Place the metal test piece in a dryer for 1 hour. Weigh each metal test piece (accurate to 0.1Img), and put it on with a 4mm diameter bolt in the order of tin, steel, aluminum, cast iron, brass, and zinc, and tighten the nuts to make the test pieces directly contact. With the cast iron test piece as the center, open the other metal test pieces to both sides, with the free ends separated by about 10mm (see Figure A2). After the assembled metal test pieces are washed with 95% ethanol, blow dry with a hair dryer, and then keep them in a desiccator for more than 1 hour. Tin-plated skin
Take the sealing ring sample and place it flat on the bottom of the sample bottle. Mix 760ml of brake fluid with 40ml of water to make a mixed brake fluid. Add 350ml of mixed brake fluid to the sample bottle. Then put the assembled metal test piece in so that its connecting end is above the sealing window and the free end is facing up.Keep it immersed until the upper end is about 1 mm from the liquid surface (see Figure B2), cover the bottle tightly, put the sample bottle into the HG/T 3612-1999
oven adjusted to (100±2)°C, take out the sample bottle from the oven after (120±2)h, cool it at room temperature for 60-90min, clamp the gold test piece group with a clamp, and let the test piece group shake fully in the brake fluid in the bottle to remove the sediment adhering to the test piece. Disassemble the metal test piece group, clean it with 95% ethanol, and then clean the test piece with absorbent cotton and ethanol, check the corrosion and spots on the surface of each test piece, and then place each test piece in a desiccator for 1h. Weigh each piece (accurate to 0.1mg). The mass change of each metal test piece is calculated according to formula (A3): Where, W,——mass before corrosion, mg,
W, mass after corrosion, mg;
Mass change (mg/cm*) = (Wz—W,)/sS——surface area of test piece (including side area), cm. The results of parallel tests show that the mass change of metal test pieces of the same type should not differ by more than 0.05 mg/cm. (A3)
Hold the sealing ring with tweezers, wash the sediment adhering to it into the test liquid and take it out, clean the sealing ring with 95% ethanol, and then dry it with a hair dryer, and check the appearance of the sealing ring for stickiness, cracks and damage. A3 Cyst resistance test
A3.1 Test device
Cryogenic box: Constant temperature to (-40±2)℃
A3.2 Test steps
Put the sealing ring in a cryogenic box at (-40±2)℃ and leave it for (22±1)h. Bend the sealing ring with your fingers until it contacts the inner wall (as shown in Figure A3). Then release your fingers immediately. Check the process of the seal returning to its original shape within 1min to see if there is any deformation. Then, remove the seal from the cryogenic box and check if there are any cracks. When performing the bending test, please wear nylon or fine cloth gloves. Figure A3 Sealing ring bending method
A4 Low temperature sealing test
A4.1 Test device and test specimen
a) Brake caliper assembly: The brake mechanism and brake device are assembled with normal parts using conventional methods. Appropriate adjustments can be made when necessary. b) Pressurizing device: The pressurizing device is a manual pressurizing device, as shown in Figure B3. The pressurizing device should be fixed at a position 300~600mm higher than the brake caliper assembly.
c) Assembly fixture: When not specified, the assembly fixture can fix the position and installation angle of the brake caliper assembly in an installation state equivalent to that of the actual vehicle (Figure A4).
Ww.bzsoso：comHG/T3612—1999
Figure A4 Assembly fixture
Brake caliper assembly
Installation components
d) Constant temperature tank: A device that can keep the brake caliper assembly in an atmosphere of (-40±2)°C. e) Lining: The lining is prepared in new, half-worn, two-thirds-worn and fully-worn states according to the thickness requirements. Or by pulling out the shims in sequence, the piston position can be moved to a position equivalent to the wear state of the above-mentioned lining. A4.2 Test steps
a) Fix the brake caliper assembly on the assembly fixture with a new pad. Expel air thoroughly. 6) Place in a low-temperature atmosphere of (-40±2)°C for 72 hours. c) Apply pressure 6 times at (1±0.07)MPa and then at (4±0.3)MPa. The hydraulic pressure interval is 60s and maintained for 5s. d) Replace the liner in a semi-worn state and use the minimum hydraulic pressure that can move the piston to move the piston to a position equivalent to the semi-worn state of the pad.
e) After the piston moves for 30 minutes, observe and record the leakage. Then place in a low-temperature nitrogen environment for 24 hours and perform c). f) Replace the liner in a two-thirds worn state and use the minimum hydraulic pressure that can move the piston to move the piston to a position equivalent to the two-thirds worn state of the pad. Www.bzxZ.net
g) Perform e).
h) Replace the fully worn pad and use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the fully worn state of the pad.
i) After the piston moves for 30 minutes, observe and record the leakage. A5 Normal temperature working durability test
A5.1 Test device and test specimen
a) Brake caliper assembly: the same as a) in A4.1. b) Pressurizing device: a dynamic pressurizing device, as shown in Figure B4, which can automatically repeat the pressurization of the brake caliper assembly with a frequency of (17+1)min-[or (1000±100)h-gate, and can load a pressure of 14MPa on the brake caliper assembly in one working stroke. c) Assembly fixture: the same as c) in A4.1. d) Lining: Use semi-worn state according to thickness requirements. A5.2 Test steps
a) After the brake caliper is assembled, fix the brake caliper assembly on the assembly fixture. Expel air fully. b) According to the following test conditions, temperature 4~～35℃, hydraulic pressure (7 on 0.3)MPa or hydraulic pressure agreed by both parties, frequency (17±1)min-=[or (1000 on 100)h-\], working times 5×10° or times agreed by both parties, carry out normal temperature working durability test. During the test period, pay attention to observe whether there is pressure drop caused by leakage of sealing ring. c) Then, carry out the following leakage test: keep it at 0.7MPa hydraulic pressure for 5min, check for leakage; keep it at 0.01MPa hydraulic pressure for 24h, check for leakage, HG/T3612—1999
d) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe it dry with a cloth. Clean the seal ring with 95% ethanol, but the cleaning time shall not exceed 30s. Then use a hair dryer to dry the seal ring. e) Visually inspect the deformation, wear and defects of the seal ring. f) Visually inspect the corrosion of the cylinder wall and piston working surface. A6 High-temperature durability test
A6. 1 Test device and test specimen
a) Brake caliper assembly, the same as a) in A4.1. b) Pressurizing device: Use the device specified in b) of A5.1. c) Assembly fixture: Use the device specified in c) of A4.1. d) Lining: The thick seat is the same as d) in A5.1. e) Constant temperature bath: It can keep the brake caliper assembly in a nitrogen environment at 120±5)℃ and (150±5)℃. A6.2 Test specimen steps
a) After the brake caliper assembly is assembled, fix the brake caliper assembly on the assembly fixture. Fully exclude air. b) Carry out high temperature working durability test according to the following test conditions, i.e., temperature for Class A is (120±5)℃; for Class B is (150±5)℃, pressure is (7±0.3)MPa or hydraulic frequency (17±1)min- or (1000±100)h-11 agreed by both parties, working time is (70±1)h or time agreed by both parties. During the test, pay attention to observe whether there is pressure drop due to seal leakage.
c) After the test is completed, stop heating and working immediately, release the residual pressure, close the thermostatic tank door, and cool for 60min. Then remove it from the tank and cool it naturally for 24h,
d) Carry out leakage test according to the method specified in c) of A5.2. e) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol, wipe it dry with a cloth, and clean the seal ring with 95% ethanol, but the cleaning time shall not exceed 30s. Then use a hair dryer to dry the sealing ring. f) Visually inspect the deformation, wear and defects of the sealing ring. g) Visually inspect the corrosion of the cylinder wall and piston working surface. WB1 Sedimentation test capacity
B2 Metal corrosion test sample bottle
Pressure container
Weighing pan bottle
HG/T 3612—1999
Appendix B
(Suggestive appendix)
Test capacity
Silicone rubber bushing
Fine hole cut, 8±0, 1
Inner diameter about 75
Outer diameter about 82
Covered
Bin sample bottle
Gold thin test piece
Sealing diagram)/sS——surface area of the test piece (including the side area), cm. The mass change of the same type of metal test pieces should not differ by more than 0.05 mg/cm. (A3)
Hold the sealing ring with tweezers, wash the sediment adhering to it into the test solution and take it out, clean the sealing ring with 95% ethanol, and then blow it dry with a hair dryer, check the appearance of the sealing ring for stickiness, cracks and damage. A3 Cyst Resistance Test
A3.1 Test Equipment
Low Temperature Box: Constant Temperature to (-40±2)℃
A3.2 Test Steps
Put the sealing ring in a low temperature box at (-40±2)℃ and leave it for (22±1)h. Bend the sealing ring with your fingers in the low temperature box until it touches the inner wall (as shown in Figure A3), then immediately release your fingers. Check the process of the seal returning to its original shape within 1min to see if there is any deformation. Then, remove the low temperature box and check whether there are cracks on the seal ring. When performing the bending test, be careful to wear nylon or fine cloth gloves. Figure A3 Sealing ring bending method
A4 Low temperature sealing test
A4.1 Test device and test specimen
a) Brake caliper assembly: The brake mechanism and brake device are assembled with normal parts using conventional methods, and appropriate adjustments can be made when necessary. b) Pressurizing device: The pressurizing device is a manual pressurizing device, as shown in Figure B3. The pressurizing device should be fixed at a position 300~600mm higher than the brake caliper assembly.
c) Assembly fixture: When not specifically specified, the assembly fixture allows the position and installation angle of the brake caliper assembly to be fixed in an installation state equivalent to that of the actual vehicle (Figure A4).
Ww.bzsoso：comHG/T3612—1999
Figure A4 Assembly fixture
Brake caliper assembly
Installation components
d) Constant temperature bath: A device that can keep the brake caliper assembly in an atmosphere of (-40±2)°C. e) Pads: Pads are prepared in new, half-worn, two-thirds-worn and fully-worn states according to thickness requirements. Or by pulling out the shims in sequence, the piston position is moved to a position corresponding to the wear state of the above-mentioned pads. A4.2 Test steps
a) Fix the brake caliper assembly on the assembly fixture with a new pad. Exhaust air thoroughly. 6) Place in a low atmosphere of (-40±2)°C for 72 hours. c) Apply axillary pressure 6 times each under the conditions of (1±0.07)MPa and then (4±0.3)MPa. Hydraulic interval is 60s and maintained for 5s. d) Replace the liner in a half-worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the half-worn state of the liner
e) After the piston moves for 30 minutes, observe and record the leakage. Then place it in a low-temperature nitrogen environment for 24 hours and perform operation c). f) Replace the liner in a two-thirds worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the two-thirds worn state of the liner.
g) Perform operation e).
h) Replace the liner in a fully worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the fully worn state of the liner.
i) After the piston moves for 30 minutes, observe and record the leakage. A5 Normal temperature working durability test
A5.1 Test device and test specimen
a) Brake caliper assembly: the same as a) in A4.1. b) Pressurizing device: It is a dynamic pressurizing device, as shown in Figure B4, which can automatically and repeatedly pressurize the brake caliper assembly, with a frequency of (17+1)min-[or (1000±100)h-door, and can load 14MPa of pressure on the brake caliper assembly in one working stroke. c) Assembly fixture: The same as c) in A4.1. d) Lining: Use semi-worn state according to thickness requirements. A5.2 Test steps
a) After the brake caliper is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, namely temperature 4~～35℃, hydraulic pressure (7+0.3)MPa or hydraulic pressure agreed by both parties, frequency (17±1)min-=[or (1000+100)h-\], working times 5×10° or times agreed by both parties, implement normal temperature working durability test. During the test, pay attention to observe whether there is a pressure drop caused by leakage of the sealing ring. c) Then, perform the following leakage test: maintain 5 minutes under 0.7MPa hydraulic pressure and check for leakage; maintain 24 hours under 0.01MPa hydraulic pressure and check for leakage. HG/T3612—1999
d) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe dry with a cloth. Clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30s. Then use a hair dryer to dry the sealing ring. e) Visually inspect the deformation, wear and defects of the sealing ring. f) Visually inspect the corrosion of the cylinder wall and piston working surface. A6 High temperature working durability test
A6. 1 Test device and test specimen
a) Brake caliper assembly, the same as a) in A4.1. b) Pressurizing device: Use the device specified in b) of A5.1. c) Assembly fixture: Use the device specified in c) of A4.1. d) Lining: The same as d) of A5.1. e) Constant temperature bath: It can keep the brake caliper assembly in a nitrogen environment at 120±5)℃ and (150±5)℃. A6.2 Test procedure
a) After the brake caliper assembly is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, the temperature is (120±5)℃ for Class A and (150±5)℃ for Class B, the pressure is (7±0.3)MPa or the hydraulic frequency agreed by the supplier and the buyer (17±1)min- or (1000±100)h-11, and the working time is (70±1)h or the time agreed by the supplier and the buyer. During the test, pay attention to observe whether there is a pressure drop due to seal leakage.
c) After the test is completed, stop heating and working immediately, release the residual pressure, close the thermostatic chamber door, and cool for 60 minutes. Then remove it from the tank and cool it naturally for 24 hours.
d) Perform a leakage test according to the method specified in c) of A5.2. e) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe them dry with a cloth, and clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30 seconds. Then use a hair dryer to dry the sealing ring. f) Visually inspect the deformation, wear and defects of the sealing ring. g) Visually inspect the corrosion of the cylinder wall and piston working surface. WB1 Sedimentation test capacity
B2 Metal corrosion test sample bottle
Pressure container
Weighing pan bottle
HG/T 3612—1999
Appendix B
(Suggestive appendix)
Test capacity
Silicone rubber bushing
Fine hole cut, 8±0, 1
Inner diameter about 75
Outer diameter about 82
Covered
Bin sample bottle
Gold thin test piece
Sealing diagram)/sS——surface area of test piece (including side area), cm. The mass change of metal test pieces of the same type shall not differ by more than 0.05 mg/cm for the results of parallel tests. (A3)
Hold the sealing ring with tweezers, wash the sediment adhering to it into the test solution and take it out, clean the sealing ring with 95% ethanol, and then blow it dry with a hair dryer, and check the appearance of the sealing ring for stickiness, cracks and damage. A3 Cyst Resistance Test
A3.1 Test Apparatus
Low Temperature Box: Constant Temperature to (-40±2)℃
A3.2 Test Steps
Put the sealing ring in a low temperature box at (-40±2)℃ and leave it for (22±1)h. Bend the sealing ring with your fingers in the low temperature box until it touches the inner wall (as shown in Figure A3), and then immediately release your fingers. Check the process of the seal returning to its original shape within 1min to see if there is any deformation. Then, remove the low temperature box and check whether there are cracks on the seal ring. When performing the bending test, be careful to wear nylon or fine cloth gloves. Figure A3 Sealing ring bending method
A4 Low temperature sealing test
A4.1 Test device and test specimen
a) Brake caliper assembly: The brake mechanism and brake device are assembled with normal parts using conventional methods, and appropriate adjustments can be made when necessary. b) Pressurizing device: The pressurizing device is a manual pressurizing device, as shown in Figure B3. The pressurizing device should be fixed at a position 300~600mm higher than the brake caliper assembly.
c) Assembly fixture: When not specifically specified, the assembly fixture allows the position and installation angle of the brake caliper assembly to be fixed according to the installation state equivalent to the actual vehicle (Figure A4).
Ww.bzsoso：comHG/T3612—1999
Figure A4 Assembly fixture
Brake caliper assembly
Installation components
d) Constant temperature bath: A device that can keep the brake caliper assembly in an atmosphere of (-40±2)°C. e) Pads: Pads are prepared in new, half-worn, two-thirds-worn and fully-worn states according to thickness requirements. Or by pulling out the shims in sequence, the piston position is moved to a position corresponding to the wear state of the above-mentioned pads. A4.2 Test steps
a) Fix the brake caliper assembly on the assembly fixture with a new pad. Exhaust air thoroughly. 6) Place in a low atmosphere of (-40±2)°C for 72 hours. c) Apply axillary pressure 6 times each under the conditions of (1±0.07)MPa and then (4±0.3)MPa. Hydraulic interval is 60s and maintained for 5s. d) Replace the liner in a half-worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the half-worn state of the liner
e) After the piston moves for 30 minutes, observe and record the leakage. Then place it in a low-temperature nitrogen environment for 24 hours and perform c). f) Replace the liner in a two-thirds worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the two-thirds worn state of the liner.
g) Perform e).
h) Replace the liner in a fully worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the fully worn state of the liner.
i) After the piston moves for 30 minutes, observe and record the leakage. A5 Normal temperature working durability test
A5.1 Test device and test specimen
a) Brake caliper assembly: the same as a) in A4.1. b) Pressurizing device: It is a dynamic pressurizing device, as shown in Figure B4, which can automatically and repeatedly pressurize the brake caliper assembly, with a frequency of (17+1)min-[or (1000±100)h-door, and can load 14MPa of pressure on the brake caliper assembly in one working stroke. c) Assembly fixture: The same as c) in A4.1. d) Lining: Use semi-worn state according to thickness requirements. A5.2 Test steps
a) After the brake caliper is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, namely temperature 4~～35℃, hydraulic pressure (7+0.3)MPa or hydraulic pressure agreed by both parties, frequency (17±1)min-=[or (1000+100)h-\], working times 5×10° or times agreed by both parties, implement normal temperature working durability test. During the test, pay attention to observe whether there is a pressure drop caused by leakage of the sealing ring. c) Then, perform the following leakage test: maintain 5 minutes under 0.7MPa hydraulic pressure and check for leakage; maintain 24 hours under 0.01MPa hydraulic pressure and check for leakage. HG/T3612—1999
d) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe dry with a cloth. Clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30s. Then use a hair dryer to dry the sealing ring. e) Visually inspect the deformation, wear and defects of the sealing ring. f) Visually inspect the corrosion of the cylinder wall and piston working surface. A6 High temperature working durability test
A6. 1 Test device and test specimen
a) Brake caliper assembly, the same as a) in A4.1. b) Pressurizing device: Use the device specified in b) of A5.1. c) Assembly fixture: Use the device specified in c) of A4.1. d) Lining: The same as d) of A5.1. e) Constant temperature bath: It can keep the brake caliper assembly in a nitrogen environment at 120±5)℃ and (150±5)℃. A6.2 Test procedure
a) After the brake caliper assembly is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, the temperature is (120±5)℃ for Class A and (150±5)℃ for Class B, the pressure is (7±0.3)MPa or the hydraulic frequency agreed by the supplier and the buyer (17±1)min- or (1000±100)h-11, and the working time is (70±1)h or the time agreed by the supplier and the buyer. During the test, pay attention to observe whether there is a pressure drop due to seal leakage.
c) After the test is completed, stop heating and working immediately, release the residual pressure, close the thermostatic chamber door, and cool for 60 minutes. Then remove it from the tank and cool it naturally for 24 hours.
d) Perform a leakage test according to the method specified in c) of A5.2. e) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe them dry with a cloth, and clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30 seconds. Then use a hair dryer to dry the sealing ring. f) Visually inspect the deformation, wear and defects of the sealing ring. g) Visually inspect the corrosion of the cylinder wall and piston working surface. WB1 Sedimentation test capacity
B2 Metal corrosion test sample bottle
Pressure container
Weighing pan bottle
HG/T 3612—1999
Appendix B
(Suggestive appendix)
Test capacity
Silicone rubber bushing
Fine hole cut, 8±0, 1
Inner diameter about 75
Outer diameter about 82
Covered
Bin sample bottle
Gold thin test piece
Sealing diagrambzsoso：comHG/T3612—1999
Figure A4 Assembly fixture
Brake caliper assembly
Installation components
d) Constant temperature bath: A device that can keep the brake caliper assembly in an atmosphere of (-40±2)°C. e) Pads: The pads are prepared in new, half-worn, two-thirds-worn and fully-worn states according to the thickness requirements. Or by pulling out the shims in sequence, the piston position is moved to a position corresponding to the wear state of the above-mentioned pads. A4.2 Test steps
a) Fix the brake caliper assembly on the assembly fixture with a new pad. Exhaust air fully. 6) Place in a low atmosphere of (-40±2)°C for 72h. c) Apply axillary pressure 6 times each under the conditions of (1±0.07)MPa and then (4±0.3)MPa. Hydraulic interval is 60s and maintained for 5s. d) Replace the liner in a half-worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the half-worn state of the liner
e) After the piston moves for 30 minutes, observe and record the leakage. Then place it in a low-temperature nitrogen environment for 24 hours and perform operation c). f) Replace the liner in a two-thirds worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the two-thirds worn state of the liner.
g) Perform operation e).
h) Replace the liner in a fully worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the fully worn state of the liner.
i) After the piston moves for 30 minutes, observe and record the leakage. A5 Normal temperature working durability test
A5.1 Test device and test specimen
a) Brake caliper assembly: the same as a) in A4.1. b) Pressurizing device: It is a dynamic pressurizing device, as shown in Figure B4, which can automatically and repeatedly pressurize the brake caliper assembly, with a frequency of (17+1)min-[or (1000±100)h-door, and can load 14MPa of pressure on the brake caliper assembly in one working stroke. c) Assembly fixture: The same as c) in A4.1. d) Lining: Use semi-worn state according to thickness requirements. A5.2 Test steps
a) After the brake caliper is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, namely temperature 4~～35℃, hydraulic pressure (7+0.3)MPa or hydraulic pressure agreed by both parties, frequency (17±1)min-=[or (1000+100)h-\], working times 5×10° or times agreed by both parties, implement normal temperature working durability test. During the test, pay attention to observe whether there is a pressure drop caused by leakage of the sealing ring. c) Then, perform the following leakage test: maintain 5 minutes under 0.7MPa hydraulic pressure and check for leakage; maintain 24 hours under 0.01MPa hydraulic pressure and check for leakage. HG/T3612—1999
d) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe dry with a cloth. Clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30s. Then use a hair dryer to dry the sealing ring. e) Visually inspect the deformation, wear and defects of the sealing ring. f) Visually inspect the corrosion of the cylinder wall and piston working surface. A6 High temperature working durability test
A6. 1 Test device and test specimen
a) Brake caliper assembly, the same as a) in A4.1. b) Pressurizing device: Use the device specified in b) of A5.1. c) Assembly fixture: Use the device specified in c) of A4.1. d) Lining: The same as d) of A5.1. e) Constant temperature bath: It can keep the brake caliper assembly in a nitrogen environment at 120±5)℃ and (150±5)℃. A6.2 Test procedure
a) After the brake caliper assembly is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, the temperature is (120±5)℃ for Class A and (150±5)℃ for Class B, the pressure is (7±0.3)MPa or the hydraulic frequency agreed by the supplier and the buyer (17±1)min- or (1000±100)h-11, and the working time is (70±1)h or the time agreed by the supplier and the buyer. During the test, pay attention to observe whether there is a pressure drop due to seal leakage.
c) After the test is completed, stop heating and working immediately, release the residual pressure, close the thermostatic chamber door, and cool for 60 minutes. Then remove it from the tank and cool it naturally for 24 hours.
d) Perform a leakage test according to the method specified in c) of A5.2. e) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe them dry with a cloth, and clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30 seconds. Then use a hair dryer to dry the sealing ring. f) Visually inspect the deformation, wear and defects of the sealing ring. g) Visually inspect the corrosion of the cylinder wall and piston working surface. WB1 Sedimentation test capacity
B2 Metal corrosion test sample bottle
Pressure container
Weighing pan bottle
HG/T 3612—1999
Appendix B
(Suggestive appendix)
Test capacity
Silicone rubber bushing
Fine hole cut, 8±0, 1
Inner diameter about 75
Outer diameter about 82
Covered
Bin sample bottle
Gold thin test piece
Sealing diagrambzsoso：comHG/T3612—1999
Figure A4 Assembly fixture
Brake caliper assembly
Installation components
d) Constant temperature bath: A device that can keep the brake caliper assembly in an atmosphere of (-40±2)°C. e) Pads: The pads are prepared in new, half-worn, two-thirds-worn and fully-worn states according to the thickness requirements. Or by pulling out the shims in sequence, the piston position is moved to a position corresponding to the wear state of the above-mentioned pads. A4.2 Test steps
a) Fix the brake caliper assembly on the assembly fixture with a new pad. Exhaust air fully. 6) Place in a low atmosphere of (-40±2)°C for 72h. c) Apply axillary pressure 6 times each under the conditions of (1±0.07)MPa and then (4±0.3)MPa. Hydraulic interval is 60s and maintained for 5s. d) Replace the liner in a half-worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the half-worn state of the liner
e) After the piston moves for 30 minutes, observe and record the leakage. Then place it in a low-temperature nitrogen environment for 24 hours and perform operation c). f) Replace the liner in a two-thirds worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the two-thirds worn state of the liner.
g) Perform operation e).
h) Replace the liner in a fully worn state, use the minimum hydraulic pressure that can move the piston to move it to the position equivalent to the fully worn state of the liner.
i) After the piston moves for 30 minutes, observe and record the leakage. A5 Normal temperature working durability test
A5.1 Test device and test specimen
a) Brake caliper assembly: the same as a) in A4.1. b) Pressurizing device: It is a dynamic pressurizing device, as shown in Figure B4, which can automatically and repeatedly pressurize the brake caliper assembly, with a frequency of (17+1)min-[or (1000±100)h-door, and can load 14MPa of pressure on the brake caliper assembly in one working stroke. c) Assembly fixture: The same as c) in A4.1. d) Lining: Use semi-worn state according to thickness requirements. A5.2 Test steps
a) After the brake caliper is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, namely temperature 4~～35℃, hydraulic pressure (7+0.3)MPa or hydraulic pressure agreed by both parties, frequency (17±1)min-=[or (1000+100)h-\], working times 5×10° or times agreed by both parties, implement normal temperature working durability test. During the test, pay attention to observe whether there is a pressure drop caused by leakage of the sealing ring. c) Then, perform the following leakage test: maintain 5 minutes under 0.7MPa hydraulic pressure and check for leakage; maintain 24 hours under 0.01MPa hydraulic pressure and check for leakage. HG/T3612—1999
d) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe dry with a cloth. Clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30s. Then use a hair dryer to dry the sealing ring. e) Visually inspect the deformation, wear and defects of the sealing ring. f) Visually inspect the corrosion of the cylinder wall and piston working surface. A6 High temperature working durability test
A6. 1 Test device and test specimen
a) Brake caliper assembly, the same as a) in A4.1. b) Pressurizing device: Use the device specified in b) of A5.1. c) Assembly fixture: Use the device specified in c) of A4.1. d) Lining: The same as d) of A5.1. e) Constant temperature bath: It can keep the brake caliper assembly in a nitrogen environment at 120±5)℃ and (150±5)℃. A6.2 Test procedure
a) After the brake caliper assembly is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) According to the following test conditions, the temperature is (120±5)℃ for Class A and (150±5)℃ for Class B, the pressure is (7±0.3)MPa or the hydraulic frequency agreed by the supplier and the buyer (17±1)min- or (1000±100)h-11, and the working time is (70±1)h or the time agreed by the supplier and the buyer. During the test, pay attention to observe whether there is a pressure drop due to seal leakage.
c) After the test is completed, stop heating and working immediately, release the residual pressure, close the thermostatic chamber door, and cool for 60 minutes. Then remove it from the tank and cool it naturally for 24 hours.
d) Perform a leakage test according to the method specified in c) of A5.2. e) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe them dry with a cloth, and clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30 seconds. Then use a hair dryer to dry the sealing ring. f) Visually inspect the deformation, wear and defects of the sealing ring. g) Visually inspect the corrosion of the cylinder wall and piston working surface. WB1 Sedimentation test capacity
B2 Metal corrosion test sample bottle
Pressure container
Weighing pan bottle
HG/T 3612—1999
Appendix B
(Suggestive appendix)
Test capacity
Silicone rubber bushing
Fine hole cut, 8±0, 1
Inner diameter about 75
Outer diameter about 82
Covered
Bin sample bottle
Gold thin test piece
Sealing diagramUse the device specified in c) of A4.1. d) Lining: The same as d) of A5.1. e) Constant temperature bath: The brake caliper assembly can be kept in a nitrogen atmosphere at 120±5)℃ and (150±5)℃. A6.2 Test procedure
a) After the brake caliper assembly is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) Carry out high temperature working durability test according to the following test conditions, that is, the temperature is (120±5)℃ for Class A and (150±5)℃ for Class B, the pressure is (7±0.3)MPa or the hydraulic frequency agreed by the supplier and the buyer (17±1)min- or (1000±100)h-11, and the working time is (70±1)h or the time agreed by the supplier and the buyer. During the test, pay attention to observe whether there is a pressure drop caused by seal leakage.
c) After the test is completed, stop heating and working immediately, release the residual pressure, close the thermostatic chamber door, and cool for 60 minutes. Then remove it from the tank and cool it naturally for 24 hours.
d) Perform a leakage test according to the method specified in c) of A5.2. e) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe them dry with a cloth, and clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30 seconds. Then use a hair dryer to dry the sealing ring. f) Visually inspect the deformation, wear and defects of the sealing ring. g) Visually inspect the corrosion of the cylinder wall and piston working surface. WB1 Sedimentation test capacity
B2 Metal corrosion test sample bottle
Pressure container
Weighing pan bottle
HG/T 3612—1999
Appendix B
(Suggestive appendix)
Test capacity
Silicone rubber bushing
Fine hole cut, 8±0, 1
Inner diameter about 75
Outer diameter about 82
Covered
Bin sample bottle
Gold thin test piece
Sealing diagramUse the device specified in c) of A4.1. d) Lining: The same as d) of A5.1. e) Constant temperature bath: The brake caliper assembly can be kept in a nitrogen atmosphere at 120±5)℃ and (150±5)℃. A6.2 Test procedure
a) After the brake caliper assembly is assembled, fix the brake caliper assembly on the assembly fixture. Exhaust air fully. b) Carry out high temperature working durability test according to the following test conditions, that is, the temperature is (120±5)℃ for Class A and (150±5)℃ for Class B, the pressure is (7±0.3)MPa or the hydraulic frequency agreed by the supplier and the buyer (17±1)min- or (1000±100)h-11, and the working time is (70±1)h or the time agreed by the supplier and the buyer. During the test, pay attention to observe whether there is a pressure drop caused by seal leakage.
c) After the test is completed, stop heating and working immediately, release the residual pressure, close the thermostatic chamber door, and cool for 60 minutes. Then remove it from the tank and cool it naturally for 24 hours.
d) Perform a leakage test according to the method specified in c) of A5.2. e) Disassemble the brake caliper assembly. Then, clean the cylinder wall and piston working surface with 95% ethanol and wipe them dry with a cloth, and clean the sealing ring with 95% ethanol, but the cleaning time shall not exceed 30 seconds. Then use a hair dryer to dry the sealing ring. f) Visually inspect the deformation, wear and defects of the sealing ring. g) Visually inspect the corrosion of the cylinder wall and piston working surface. WB1 Sedimentation test capacity
B2 Metal corrosion test sample bottle
Pressure container
Weighing pan bottle
HG/T 3612—1999
Appendix B
(Suggestive appendix)
Test capacity
Silicone rubber bushing
Fine hole cut, 8±0, 1
Inner diameter about 75
Outer diameter about 82
Covered
Bin sample bottle
Gold thin test piece
Sealing diagram
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