Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
The complete text of this standard is mandatory.
This standard is developed in accordance with the rules given in GB/T 1.1-2009.
It replaces GB 5763-2008 Brake linings for automobiles. The following changes have been made with respect to GB 5763-2008:
——“The provisions are mandatory” is changed to “the complete text of this standard is mandatory” (see Foreword; Foreword of Edition 2008);
——Normative references are modified (see clause 2; clause 2 of Edition 2008);
——Terms and definitions are modified completely (see clause 3; clause 3 of Edition 2008);
——Classification is deleted (see clause 4 of Edition 2008);
——“Technical requirements” is changed to “Basic requirements related to health and safety” (see clause 4; clause 5 of 2008 edition);
——Technical requirements for “appearance quality”, “dimensional deviation”, “impact strength”, “thermal expansion rate” and “compression strain” and their corresponding test methods are deleted (5.1, 5.2, 5.5, 5.6 and 5.7 as well as 6.1, 6.2, 6.4, 6.5, 6.6 and 6.7 of Edition 2008);
——Requirements for “limit of harmful ingredients” and their test methods are added (see 4.1, 5.1 and 5.2);
——Requirements for friction performance are changed from “coefficient of friction, tolerance and friction rate of appointed coefficient of friction at each test temperature of constant speed friction test” to “coefficient of friction at the normal temperature and at the high temperature of small sample bench test for drum linings used in vehicles of Categories M1, M2, N1, O1 and O2” and “operational coefficient of friction deviation and the like of drag test for friction performance of drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 as well as for disk linings” and the test methods are changed correspondingly (see 4.2 and 5.3; 5.3 and 6.3 of Edition 2008);
——Requirements that "The shear strength of bonding rubber-based drum lining shall not be less than 1.0MPa at ambient temperature; lining area left on the shoe iron shall not be less than 70% after test” are added (see 4.3);
——Inspection rules are changed correspondingly (see clause 6; clause 7 of Edition 2008);
——Batching principle is changed from “the actually delivered linings of the same material and specification are regarded as a batch” to “the products are divided into three categories according to disc linings; drum linings used in vehicles of Categories M1, M2, N1, O1 and O2; and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4. The actually delivered linings produced according to the same formula and process and in the same month are regarded as a batch” (see 6.2; 7.2.1 of Edition 2008);
——“the non-working surface of lining shall be printed with manufacturer's name or trademark” is changed to “the non-working surface of lining shall be printed with manufacturer's name (abbreviation) or trademark (code)” (see 7.1.1; 8.1.1 of Edition 2008);
——“There shall be appointed coefficient of friction printed” on the packaging box is changed to “drum linings used in vehicles of Categories M1, M2, N1, O1 and O2 shall also be marked with class code of coefficient of friction; drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 and disc linings shall also be marked with appointed coefficient of friction” (see 7.1.2; 8.1.2 of Edition 2008).
This standard was proposed by and is under the jurisdiction of the Ministry of Industry and Information Technology of the People's Republic of China.
The previous editions of the standard are as follows:
——GB 5763-1986, GB 5763-1998 and GB 5763-2008.
Brake linings for automobiles
1 Scope
This standard specifies terms and definitions, basic requirements related to health and safety, test methods, inspection rules, marking, packaging, transportation and storage, etc. of brake linings for automobiles.
It is applicable to brake linings for automobiles (hereinafter referred to as linings).
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 5620 Road vehicles - braking of automotive vehicles and their trailers - Vocabulary
GB/T 15089 Classification of power-driven vehicles and trailers
GB/T 17469 Characteristics evaluation of brake linings for automobile - Small sample bench test method
GB/T 22309 Road vehicles - Brake linings - Shear test procedure for disc break pad and drum brake shoe assemblies
GB/T 23263 Determination of asbestos in products
GB/T 34007 Road vehicles - Brake lining friction materials - Drag test method for friction performance
JC/T 2268 Measurement of copper and other elements in brake friction materials
3 Terms and definitions
For the purposes of this standard, the terms and definitions specified in GB/T 5620 and GB/T 15089 as well as the following ones apply.
3.1
coefficient of friction
ratio of the tangential force (i.e. friction force) impeding the relative movement of two objects to the normal force acted on the object surface
3.2
coefficient of friction at the normal temperature
μnormal temperature
average of coefficient of friction at 4 temperatures, i.e. 93℃, 121℃, 149℃ and 204℃ in the second fade test of small sample bench test, see GB/T 17469 for details
3.3
coefficient of friction at the high temperature
μhigh temperature
average of coefficient of friction at 10 temperatures, i.e. 204℃ and 149℃ in the first recovery test, 232℃, 260℃, 288℃, 316℃ and 343℃ in the second fade test and 260℃, 204℃ and 149℃ in the second recovery test of small sample bench test, see GB/T 17469 for details
3.4
classification for coefficient of friction
coefficient of friction, divided into 6 classes, i.e. C, D, E, F, G and H, in an order from small to large in small sample bench test, see GB/T 17469 for details. For drum linings used in in vehicles of Categories M1, M2, N1, O1 and O2, their coefficients of friction are expressed in class code alphabets, in which the first one represents the coefficient of friction at the normal temperature and the second one represents the coefficient of friction at the high temperature
3.5
operational coefficient of friction
μoperational
when the disc linings used in vehicles of Categories M1, M2, N1, O1 and O2 are subjected to drag test for friction performance, the average of coefficient of friction measured in the first braking operation of each braking cycle with test serial number of 3 and 4 in constant pressure mode or the average of coefficient of friction measured in the first braking operation of each braking cycle with test serial number of 3, 5 and 7 in constant torque mode, see GB/T 34007 for details
3.6
operational 1 coefficient of friction
μoperational 1
when disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 are subjected to drag test for friction performance, the average of coefficient of friction measured in 5 braking operations with test serial number of 2 in constant pressure mode, see GB/T 34007 for details
3.7
operational 2 coefficient of friction
μoperational 2
when disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 are subjected to drag test for friction performance, the average of coefficient of friction measured in 10 braking operations with test serial number of 10 in constant pressure mode, see GB/T 34007 for details
3.8
appointed coefficient of friction
the value of operational coefficient of friction expressed in the drag test method for friction performance appointed by manufacturer of the lining, which depends on the formula and production process of the lining
Disc linings used in in vehicles of Categories M1, M2, N1, O1 and O2 are expressed as PA + appointed coefficient of friction in constant pressure mode test of original sample method, PS + appointed coefficient of friction in constant pressure mode test of sampling method, MA + appointed coefficient of friction in constant torque mode test of original sample method and MS + appointed coefficient of friction in constant torque mode test of original sampling method.
Disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 are expressed as PS + appointed operational 1 coefficient of friction/appointed operational 2 coefficient of friction
4 Basic requirements related to health and safety
4.1 Limit of harmful ingredients
4.1.1 Asbestos shall not be contained in the lining.
4.1.2 Other harmful elements in the lining shall not exceed the limits as specified in Table 1.
Table 1
Name of harmful element Limits (mass fraction) %
Cadmium ≤0.01
Hexavalent chromium ≤0.1
Lead ≤0.1
Mercury ≤0.1
4.2 Friction performance
4.2.1 Small sample bench test results of drum linings used in vehicles of Categories M1, M2, N1, O1 and O2 shall meet the following requirements:
a) μnormal temperature shall not be less than 0.25 and shall meet the specified class.
b) μhigh temperature shall not be less than 0.25 and shall meet the specified class.
c) The coefficient of friction at any point of temperature range of 93℃ to 288℃ in the second fade and temperature range of 149℃ to 93℃ in the second recovery of 5 tests is not less than 0.15; and difference between the coefficients of friction at each temperature point and average of the five tests is no more than 20%.
4.2.2 Test results of the drag test for friction performance of disc linings used in vehicles of Categories M1, M2, N1, O1 and O2 shall meet the following requirements:
a) μoperational is within ±15% of the appointed coefficient of friction;
b) after the test, the lining shall be free from delamination or falling off.
4.2.3 Test results of the drag test for friction performance of disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 shall meet the following requirements:
a) μoperational 1 and μoperational 2 are within ±15% of the appointed coefficient of friction respectively;
b) after the test, the lining shall be free from delamination or falling off.
4.3 Shear strength
4.3.1 The shear strength of bonding resin-based drum lining shall not be less than 1.5MPa at ambient temperature.
Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Basic requirements related to health and safety 5 Test methods 6 Inspection rules 7 Marking, packaging, transportation and storage
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
The complete text of this standard is mandatory.
This standard is developed in accordance with the rules given in GB/T 1.1-2009.
It replaces GB 5763-2008 Brake linings for automobiles. The following changes have been made with respect to GB 5763-2008:
——“The provisions are mandatory” is changed to “the complete text of this standard is mandatory” (see Foreword; Foreword of Edition 2008);
——Normative references are modified (see clause 2; clause 2 of Edition 2008);
——Terms and definitions are modified completely (see clause 3; clause 3 of Edition 2008);
——Classification is deleted (see clause 4 of Edition 2008);
——“Technical requirements” is changed to “Basic requirements related to health and safety” (see clause 4; clause 5 of 2008 edition);
——Technical requirements for “appearance quality”, “dimensional deviation”, “impact strength”, “thermal expansion rate” and “compression strain” and their corresponding test methods are deleted (5.1, 5.2, 5.5, 5.6 and 5.7 as well as 6.1, 6.2, 6.4, 6.5, 6.6 and 6.7 of Edition 2008);
——Requirements for “limit of harmful ingredients” and their test methods are added (see 4.1, 5.1 and 5.2);
——Requirements for friction performance are changed from “coefficient of friction, tolerance and friction rate of appointed coefficient of friction at each test temperature of constant speed friction test” to “coefficient of friction at the normal temperature and at the high temperature of small sample bench test for drum linings used in vehicles of Categories M1, M2, N1, O1 and O2” and “operational coefficient of friction deviation and the like of drag test for friction performance of drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 as well as for disk linings” and the test methods are changed correspondingly (see 4.2 and 5.3; 5.3 and 6.3 of Edition 2008);
——Requirements that "The shear strength of bonding rubber-based drum lining shall not be less than 1.0MPa at ambient temperature; lining area left on the shoe iron shall not be less than 70% after test” are added (see 4.3);
——Inspection rules are changed correspondingly (see clause 6; clause 7 of Edition 2008);
——Batching principle is changed from “the actually delivered linings of the same material and specification are regarded as a batch” to “the products are divided into three categories according to disc linings; drum linings used in vehicles of Categories M1, M2, N1, O1 and O2; and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4. The actually delivered linings produced according to the same formula and process and in the same month are regarded as a batch” (see 6.2; 7.2.1 of Edition 2008);
——“the non-working surface of lining shall be printed with manufacturer's name or trademark” is changed to “the non-working surface of lining shall be printed with manufacturer's name (abbreviation) or trademark (code)” (see 7.1.1; 8.1.1 of Edition 2008);
——“There shall be appointed coefficient of friction printed” on the packaging box is changed to “drum linings used in vehicles of Categories M1, M2, N1, O1 and O2 shall also be marked with class code of coefficient of friction; drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 and disc linings shall also be marked with appointed coefficient of friction” (see 7.1.2; 8.1.2 of Edition 2008).
This standard was proposed by and is under the jurisdiction of the Ministry of Industry and Information Technology of the People's Republic of China.
The previous editions of the standard are as follows:
——GB 5763-1986, GB 5763-1998 and GB 5763-2008.
Brake linings for automobiles
1 Scope
This standard specifies terms and definitions, basic requirements related to health and safety, test methods, inspection rules, marking, packaging, transportation and storage, etc. of brake linings for automobiles.
It is applicable to brake linings for automobiles (hereinafter referred to as linings).
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 5620 Road vehicles - braking of automotive vehicles and their trailers - Vocabulary
GB/T 15089 Classification of power-driven vehicles and trailers
GB/T 17469 Characteristics evaluation of brake linings for automobile - Small sample bench test method
GB/T 22309 Road vehicles - Brake linings - Shear test procedure for disc break pad and drum brake shoe assemblies
GB/T 23263 Determination of asbestos in products
GB/T 34007 Road vehicles - Brake lining friction materials - Drag test method for friction performance
JC/T 2268 Measurement of copper and other elements in brake friction materials
3 Terms and definitions
For the purposes of this standard, the terms and definitions specified in GB/T 5620 and GB/T 15089 as well as the following ones apply.
3.1
coefficient of friction
ratio of the tangential force (i.e. friction force) impeding the relative movement of two objects to the normal force acted on the object surface
3.2
coefficient of friction at the normal temperature
μnormal temperature
average of coefficient of friction at 4 temperatures, i.e. 93℃, 121℃, 149℃ and 204℃ in the second fade test of small sample bench test, see GB/T 17469 for details
3.3
coefficient of friction at the high temperature
μhigh temperature
average of coefficient of friction at 10 temperatures, i.e. 204℃ and 149℃ in the first recovery test, 232℃, 260℃, 288℃, 316℃ and 343℃ in the second fade test and 260℃, 204℃ and 149℃ in the second recovery test of small sample bench test, see GB/T 17469 for details
3.4
classification for coefficient of friction
coefficient of friction, divided into 6 classes, i.e. C, D, E, F, G and H, in an order from small to large in small sample bench test, see GB/T 17469 for details. For drum linings used in in vehicles of Categories M1, M2, N1, O1 and O2, their coefficients of friction are expressed in class code alphabets, in which the first one represents the coefficient of friction at the normal temperature and the second one represents the coefficient of friction at the high temperature
3.5
operational coefficient of friction
μoperational
when the disc linings used in vehicles of Categories M1, M2, N1, O1 and O2 are subjected to drag test for friction performance, the average of coefficient of friction measured in the first braking operation of each braking cycle with test serial number of 3 and 4 in constant pressure mode or the average of coefficient of friction measured in the first braking operation of each braking cycle with test serial number of 3, 5 and 7 in constant torque mode, see GB/T 34007 for details
3.6
operational 1 coefficient of friction
μoperational 1
when disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 are subjected to drag test for friction performance, the average of coefficient of friction measured in 5 braking operations with test serial number of 2 in constant pressure mode, see GB/T 34007 for details
3.7
operational 2 coefficient of friction
μoperational 2
when disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 are subjected to drag test for friction performance, the average of coefficient of friction measured in 10 braking operations with test serial number of 10 in constant pressure mode, see GB/T 34007 for details
3.8
appointed coefficient of friction
the value of operational coefficient of friction expressed in the drag test method for friction performance appointed by manufacturer of the lining, which depends on the formula and production process of the lining
Disc linings used in in vehicles of Categories M1, M2, N1, O1 and O2 are expressed as PA + appointed coefficient of friction in constant pressure mode test of original sample method, PS + appointed coefficient of friction in constant pressure mode test of sampling method, MA + appointed coefficient of friction in constant torque mode test of original sample method and MS + appointed coefficient of friction in constant torque mode test of original sampling method.
Disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 are expressed as PS + appointed operational 1 coefficient of friction/appointed operational 2 coefficient of friction
4 Basic requirements related to health and safety
4.1 Limit of harmful ingredients
4.1.1 Asbestos shall not be contained in the lining.
4.1.2 Other harmful elements in the lining shall not exceed the limits as specified in Table 1.
Table 1
Name of harmful element Limits (mass fraction) %
Cadmium ≤0.01
Hexavalent chromium ≤0.1
Lead ≤0.1
Mercury ≤0.1
4.2 Friction performance
4.2.1 Small sample bench test results of drum linings used in vehicles of Categories M1, M2, N1, O1 and O2 shall meet the following requirements:
a) μnormal temperature shall not be less than 0.25 and shall meet the specified class.
b) μhigh temperature shall not be less than 0.25 and shall meet the specified class.
c) The coefficient of friction at any point of temperature range of 93℃ to 288℃ in the second fade and temperature range of 149℃ to 93℃ in the second recovery of 5 tests is not less than 0.15; and difference between the coefficients of friction at each temperature point and average of the five tests is no more than 20%.
4.2.2 Test results of the drag test for friction performance of disc linings used in vehicles of Categories M1, M2, N1, O1 and O2 shall meet the following requirements:
a) μoperational is within ±15% of the appointed coefficient of friction;
b) after the test, the lining shall be free from delamination or falling off.
4.2.3 Test results of the drag test for friction performance of disc and drum linings used in vehicles of Categories M3, N2, N3, O3 and O4 shall meet the following requirements:
a) μoperational 1 and μoperational 2 are within ±15% of the appointed coefficient of friction respectively;
b) after the test, the lining shall be free from delamination or falling off.
4.3 Shear strength
4.3.1 The shear strength of bonding resin-based drum lining shall not be less than 1.5MPa at ambient temperature.
Contents of GB 5763-2018
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Basic requirements related to health and safety
5 Test methods
6 Inspection rules
7 Marking, packaging, transportation and storage
