Test method for inertia absorption durability of friction elements in wet automatic transmission
1 Scope
This document specifies the test equipment and preparation, test procedures, test data, precision and test report used for the test method for inertia absorption durability of friction elements in wet automatic transmission.
This document is applicable to the determination of inertia absorption durability of friction elements in wet automatic transmission for passenger cars and commercial vehicles. Other types of friction elements in automatic transmission may be used with reference to this document.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions 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 8170 Rules of rounding off for numerical values & expression and judgement of limiting values
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
friction characteristics
unique intrinsic properties of friction materials (friction elements) during friction process
Note: In this document, dynamic and static friction tests are adopted to evaluate the friction characteristics of friction elements in automatic transmission.
3.2
friction coefficient
ratio of the friction force to the force exerted on the friction element when there is or tends to be relative motion between the friction plate and the dual disc
Notes
1 The friction coefficient is classified as dynamic one and static one.
2 The dynamic and static friction coefficients are calculated using Equation (1), and the results are rounded to 3 decimals according to GB/T 8170.
(1)
where,
μ——the friction coefficient;
T——the friction torque, N.m;
n——the number of friction plates (n=3);
r——the radius of average effective friction, mm, taken as 57.4mm;
p——the surface pressure loaded on the friction surface of friction plate, kPa, taken as 785kPa;
A——the friction area of friction plate, mm2, taken as 4,434mm2.
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Test equipment and preparation
5 Test procedures
6 Test data
7 Precision
8 Test report
Annex A (Informative) Dimensions and requirements of friction plate and dual disc
Annex B (Informative) Example tables of the test report
Bibliography
Test method for inertia absorption durability of friction elements in wet automatic transmission
1 Scope
This document specifies the test equipment and preparation, test procedures, test data, precision and test report used for the test method for inertia absorption durability of friction elements in wet automatic transmission.
This document is applicable to the determination of inertia absorption durability of friction elements in wet automatic transmission for passenger cars and commercial vehicles. Other types of friction elements in automatic transmission may be used with reference to this document.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions 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 8170 Rules of rounding off for numerical values & expression and judgement of limiting values
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
friction characteristics
unique intrinsic properties of friction materials (friction elements) during friction process
Note: In this document, dynamic and static friction tests are adopted to evaluate the friction characteristics of friction elements in automatic transmission.
3.2
friction coefficient
ratio of the friction force to the force exerted on the friction element when there is or tends to be relative motion between the friction plate and the dual disc
Notes
1 The friction coefficient is classified as dynamic one and static one.
2 The dynamic and static friction coefficients are calculated using Equation (1), and the results are rounded to 3 decimals according to GB/T 8170.
(1)
where,
μ——the friction coefficient;
T——the friction torque, N.m;
n——the number of friction plates (n=3);
r——the radius of average effective friction, mm, taken as 57.4mm;
p——the surface pressure loaded on the friction surface of friction plate, kPa, taken as 785kPa;
A——the friction area of friction plate, mm2, taken as 4,434mm2.
Contents of GB/T 41607-2022
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Test equipment and preparation
5 Test procedures
6 Test data
7 Precision
8 Test report
Annex A (Informative) Dimensions and requirements of friction plate and dual disc
Annex B (Informative) Example tables of the test report
Bibliography
