The purpose of this SAE Recommended Practice is to establish a uniform laboratory procedure for securing and reporting the friction and wear characteristics of brake linings. The performance data obtained can be used for in-plant quality control by brake lining manufacturers and for the quality assessment of incoming shipments by the purchasers of brake linings.
The purpose of this SAE Recommended Practice is to establish a uniform laboratory procedure for securing and reporting the friction and wear characteristics of brake linings. The performance data obtained can be used for in-plant quality control by brake lining manufacturers and for the quality assessment of incoming shipments by the purchasers of brake linings.
The purpose of this SAE Recommended Practice is to establish a uniform laboratory procedure for securing and reporting the friction and wear characteristics of brake linings. The performance data obtained can be used for in-plant quality control by brake lining manufacturers and for the quality assessment of incoming shipments by the purchasers of brake linings.
Specific gravity is a nondestructive test used as a quality control check of the consistency of formulation and processing of brake lining. Specific gravity alone shows nothing about a lining’s ability to develop friction or to resist fade when used as a friction element in brakes. Specific gravity varies with the formulation of the lining. The specific gravity of sintered metal powder linings, particularly those which have steel backing members, is usually determined somewhat differently. Reference ASTM B 376 “Density of Sintered Metal Friction Material” (latest revision).1 The specific gravity and the range of specific gravity are peculiar to each formulation and, therefore, the acceptable values or range must be established for each formulation by the manufacturer.
This SAE Recommended Practice is intended to provide a uniform means of identification which may be used to describe the initial friction characteristics only of brake blocks (see SAE J660, Brake Linings) for use on commercial vehicles. NOTE: It is emphasized that this recommended practice does not establish friction requirements for brake blocks, nor does it designate other significant block characteristics which must also be considered in overall brake performance. The basis for determining the friction coefficients for brake blocks are tests conducted in accordance with SAE J661, Brake Lining Quality Control Test Procedures.
This SAE Recommended Practice is intended to provide a uniform means of identification which may be used to classify the friction coefficient of brake linings, based on data obtained from tests conducted in accordance with SAE J661.
This SAE Recommended Practice is intended to provide a uniform means of identification which may be used to classify the friction coefficient of brake linings, based on data obtained from tests conducted in accordance with SAE J661 Brake Lining Quality Test Procedure and SAE J2975 Measurement of Copper and other elements in Brake Friction Materials. NOTE: It is emphasized that this document does not establish friction requirements for brake linings, nor does it designate significant characteristics of brake linings which must be considered in overall brake performance. Due to other factors that include brake system design and operating environment, the friction codes obtained from this document cannot reliably be used to predict brake system performance.
This SAE Recommended Practice is intended to provide a uniform means of identification which may be used to classify the friction coefficient of brake linings, based on data obtained from tests conducted in accordance with SAE J661 Brake Lining Quality Test Procedure and SAE J2975 Measurement of Copper and other elements in Brake Friction Materials. NOTE: It is emphasized that this document does not establish friction requirements for brake linings, nor does it designate significant characteristics of brake linings which must be considered in overall brake performance. Due to other factors that include brake system design and operating environment, the friction codes obtained from this document cannot reliably be used to predict brake system performance.
Gogan hardness, a nondestructive (a penetrator causes shallow surface deformation) method of measuring compressibility, is used as a quality control check of the consistency of formulation and processing of brake lining. Gogan hardness alone shows nothing about a lining’s ability to develop friction or to resist fade when used as a friction element in brakes. Gogan hardness varies with formulation, contour, and thickness of the lining. The hardness of sintered powder metal lining is usually determined with Rockwell Superficial hardness equipment. Reference ASTM B 3471 (latest revision) “Standard Method of Test for Hardness of Sintered Metal Friction Materials.” The Gogan hardness and the range of Gogan hardness are peculiar to each formulation, thickness, and contour and, therefore, the acceptable values or range must be established for each formulation and part configuration by the manufacturer.
Gogan hardness, a nondestructive (a penetrator causes shallow surface deformation) method of measuring compressibility, is used as a quality control check of the consistency of formulation and processing of brake lining. Gogan hardness alone shows nothing about a lining's ability to develop friction or to resist fade when used as a friction element in brakes. Gogan hardness varies with formulation, contour, and thickness of the lining. The Gogan hardness and the range of Gogan hardness are peculiar to each formulation, thickness, and contour and, therefore, the acceptable values or range must be established for each formulation and part configuration by the manufacturer.
Gogan hardness, a nondestructive (a penetrator causes shallow surface deformation) method of measuring compressibility, is used as a quality control check of the consistency of formulation and processing of brake lining. Gogan hardness alone shows nothing about a lining’s ability to develop friction or to resist fade when used as a friction element in brakes. Gogan hardness varies with formulation, contour, and thickness of the lining. The Gogan hardness and the range of Gogan hardness are peculiar to each formulation, thickness, and contour and, therefore, the acceptable values or range must be established for each formulation and part configuration by the manufacturer.
Hardness measurements are used as a quality control check of the consistency of formulation and processing of brake linings. Gogan hardness is nondestructive (the penetrator causes shallow surface deformation.). Gogan hardness method alone does not show anything about a lining’s ability to develop friction or to resist fade when used as a friction element in brakes. The hardness and the range of hardness are peculiar to each formulation, thickness, and contour; therefore, the acceptable values and ranges must be established for each formulation and part configuration by the manufacturer.
Hardness measurements are used as a quality control check of the consistency of formulation and processing of brake linings. Gogan hardness is nondestructive (the penetrator causes shallow surface deformation.). Gogan hardness method alone does not show anything about a lining’s ability to develop friction or to resist fade when used as a friction element in brakes. The hardness and the range of hardness are peculiar to each formulation, thickness, and contour; therefore, the acceptable values and ranges must be established for each formulation and part configuration by the manufacturer.
Hardness measurements are used as a quality control check of the consistency of formulation and processing of brake linings. Gogan hardness is nondestructive (the penetrator causes shallow surface deformation.). Gogan hardness method alone does not show anything about a lining’s ability to develop friction or to resist fade when used as a friction element in brakes. The hardness and the range of hardness are peculiar to each formulation, thickness, and contour; therefore, the acceptable values and ranges must be established for each formulation and part configuration by the manufacturer.
Hardness measurements are used as a quality control check of the consistency of formulation and processing of brake linings. This hardness method is nondestructive. NOTE—This method is not a measure of friction level. The hardness and the range of hardness are characteristic of each formulation; therefore, the acceptable values and ranges must be established for each formulation and may be affected by processing. NOTE—The hardness of sintered powder metal lining is usually determined with Rockwell superficial hardness equipment. (See ASTM B 347)
Hardness measurements are used as a quality control check of the consistency of formulation and processing of brake linings. This hardness method is nondestructive. The hardness and the range of hardness are characteristic of each formulation; therefore, the acceptable values and ranges must be established for each formulation and may be affected by processing.
Hardness measurements are used as a quality control check of the consistency of formulation and processing of brake linings. This hardness method is nondestructive. The hardness and the range of hardness are characteristic of each formulation; therefore, the acceptable values and ranges must be established for each formulation and may be affected by processing.