1、 ENGINEERING MATERIAL SPECIFICATIONDate Action Revisions 2010 06 25 N-STATUS No replacement named C. Mracna, NA 2004 06 30 Revised Para 3.0 inserted; para 3.5 & 4 deleted 1963 06 21 Released F6-1068 Printed copies are uncontrolled Copyright 2010, Ford Global Technologies, LLC Page 1 of 2 NITRILE BUT
2、ADIENE RUBBER, HARD CELLULAR COMPOUND - ESF-M2D74-A FUEL RESISTANT NOT TO BE USED FOR NEW DESIGN 1. SCOPE The material defined by this specification is a hard cellular nitrile butadiene rubber composition. It is written around the lowest density of 160 - 190 kg/m3and equal or better performance may
3、be expected of the higher densities. 2. APPLICATION This specification was released originally for material used as a float for carburetors or fuel tank sending units, where resistance to hydro-carbon fuels is required. 3. REQUIREMENTS 3.0 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material supp
4、liers and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.1 ABSORPTION With a smooth sawcut, section the part approximately in half. The cut is to be oriented along the axis of the hole, or so as to remove any molded-in insert, as applic
5、able. Immerse the remaining specimen in a mixture of two volumes of ASTM Fuel C with one volume of anhydrous ethanol. Attach a reflux condenser to the vessel and heat 24 h at 60 C. The specimen should increase in weight no more than 30%. The appearance of the specimen should not change appreciably,
6、but a slight softness may be noted. 3.2 TEMPERATURE The parts may soften at approximately 116 C and at higher temperatures may expand due to the pressure of the entrapped gas. The material should not melt or become sticky but may be subject to thermal shock and may crack if heated rapidly to high te
7、mperatures. 3.3 FUEL RESISTANCE To be run for initial sample approval and at intervals as specified. The parts must withstand weight, volume and hardness changes when immersed for 24 h at 60 C according to ASTM D 471, in the following fuels and blends: Note: Parts to be checked as received. ENGINEER
8、ING MATERIAL SPECIFICATIONESF-M2D74-APrinted copies are uncontrolled Copyright 2010, Ford Global Technologies, LLC Page 2 of 2 Floats with Inserts Floats Without Inserts % Weight % Volume % Weight % Volume Fuel or Blend Change Change Change Change Commercial Gasoline -2, +2 -2, +2 -2, +2 -2, +2 ASTM
9、 Fuel C -3, +3 -3, +3 -3, +3 -3, +3 Anhydrous Methanol 0, +25 +5, +20 0, +45 0, +20 Anhydrous Ethanol 0, +10 -1, +6 0, +15 -1, +6 10% Butyl Acetate & 90% Iso-octane 0, +2 -2, +2 0, +2 -2, +2 10% Acetone & 90% Iso-octane 0, +3 -2, +2 0, +3 -2, +2 Sour Gasoline -1, +4 -2, +2 -1, +4 -2, +2 (See FLTM AZ 105-01 for content) 3.4 SURFACE The part shall have a smooth surface and its normal skin acquired through the molding process should not be disturbed in any manner.
