1 Scope
This standard specifies the performance requirements and test methods for brake caliper assembly of limousine hydraulic disk brake.
This standard is applicable to the brake caliper assembly of limousine brake fluid system; the automobile with total mass below 3.5 tons may also comply with this standard.
2 Normative References
The following standards contain provisions which, through reference in this standard, constitute provisions of this standard. Where this standard is published, the editions indicated are valid. All standards are subject to revision, and parties to agreements based on this code are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below.
QCn 29008.13-1991 Automobile Quality Inspection—Cleanliness Evaluation Method
QC/T 316-1999 Bench Test Methods of Fatigue Strength for Automobile Service Brake
3 Definitions
This standard adopts the following definitions:
3.1 Required fluid volume
Brake fluid volume which need be injected to keep certain hydraulic pressure inside brake caliper.
3.2 Drag torque
Residual rotational resistance torque of brake disc after the hydraulic pressure of brake is released.
3.3 Wear condition of brake pad
The condition where the friction material of brake pad is worn down to only 2mm in thickness
4 Performance Requirements
4.1 The products shall meet the requirements of this standard and shall be manufactured according to the approved pattern and technical documents of established procedure.
4.2 Sealing performance
4.2.1 Low-pressure sealability
The brake caliper assembly shall be carried out with low-pressure sealability test according to 5.1.1; its pressure drop shall be less than or equal to 0.01MPa.
4.2.2 High-pressure sealability
The brake caliper assembly shall be carried out with high-pressure sealability test according to 5.1.2; its pressure drop shall be less than or equal to 0.2MPa.