Document OEkgdOM9kYpa072bO6K7D15Dp

DONT BE SOLD ... ON THE BASIS OF EDGE CODE H In 1966 several states enacted legislation requiring brake linings and thick blocks to be identified with markings on the edge of the material. These markings carry the manufacturers' identification, a numeric code, and alpha characters indicating the initial friction properties of the material, i.e. ABEX685 FF.Thls marking is commonly referred to as an "edge code". The alpha character code is determined in accordance with SAE Standard Recommended Practice J866a. This SAE Standard is the basis for friction coding of all brake linings and brake blocks. American Brakeblok feels that it is important that you understand the meaning of this coding and the following is a verbatim reproduction of SAE J866a. FRICTION IDENTIFICATION SYSTEM FOR BRAKE LININGS AND BRAKE BLOCKS FOR MOTOR VEHICLES -- SAE J866a SAE Recommended Practice Report of Brake Committee approved Marck 1964 and Uat revUcd September 1966. Editorial chance May 1967. S^ofr-Thit SAE Recommended Practice is intended to provide a uniform means of identification which may be used to describe the initial friction characteristics of brake linings and brake blocks for use on motor vehicles. NOTE: It Is emphasized (hat this recommended practice does not establish friction requirements for brake linings or brake blocks, nor docs it designate other significant characteristics of brake linings or brake blocks which must also be considered in overall brake perform ance. The basis for determining the friction coefficients for brake linings and brake blocks are tests conducted in accordance with SAE J661. Coding--The code will consist of two letters reflecting the friction coefficients as follows: Coefficient of Friction c Mo* owr 0.15 c0 Ov< 0.(5 bf aM M*r 0.25 (Kw 0.25 b<4 Ml oY+t OJj c9 Ovr 0.35 Ml ov*v 0.45 Ovr 0.43 but Ml ovar 0J5 M Ora* 0.5 S Z The first letter will represent normal friction coefficient and the second letter will represent hot friction coefficient Normal Friction Coefficient--Normal friction coefficient Is defined as the average of 4 points on the second fade curve, located at 200, 250, 300, and 4Q0 F. Hot Friction Coefficient--Hot friction coefficient^* defined as the average of 10 points located at 400 and S00 F on the first recovery: 450, 500, 550, GOO, and 650 F on (he second fade; and 500, 400, and 300 F on the second recovery. NOTE: If any temperature point or points required to calculate friction coefficients are not reached in the prescribed time limit, (he coefficient of friction value a( 10 minutes shall be used to give the full number of points required. Example: A lining having a normal friction coefficient of 0.29 and a hot friction coefficient of 0.40 would be coded MEF." Location of Code--The appropriate code designation will be marked on an external noncontacting surface In letters not less than 0.125 In, In height. There are several significant points in SAE J866a which should be emphasized. Reference is made to SAE J661a which is the test procedure used to determine the friction coding. A friction materials test machine, better known as a Chase machine, is used to run the test. This machine, using a 1" by 1" sample piece of friction material, measures coefficient of friction under several varying conditions of temperature, pressure, and rubbing speed. The actual function of the brake is not taken into account. Consequently, as noted in SAE Standard J866a, THIS TEST DOES NOT DESIGNATE OTHER SIGNIFICANT CHARACTERISTICS OF BRAKE LININGS OR BRAKE BLOCKS WHICH MUST ALSO BE CONSIDERED IN OVERALL BRAKE PERFORMANCE. Continued on back SCF-NAPA-0061 NOVO17047