1、FORD WORLDWIDE FASTENER STANDARDDate: 1993-01-01Engineering Standards & 1 of 1 Printed copies are uncontrolled .Systems Engineering (ESSE)WE 980Paint Clearing Nuts - Performance1. SCOPE.This specification covers the performance requirements of ISO metric nuts with a paint clearing featureincorporate
2、d and with physical properties in accordance with WE 952.1.1 REFERENCES.WSK-M64J29-C1-C3 - Waterborne electrocoatWSK-M6J160-A1 - Primer surfacer, coloured, PU modified polyester, mediumsolid, 165oC baking temperature.WSD-M50J111-A - Paint, medium solid polyester, baking, exterior topcoat.2. PERFORMA
3、NCE TESTING.2.1 CROSS THREADING TEST. The nut must be initially misaligned with the center-line of the testscrew thread by 5 +/- 1 o and when assembly is attempted using a 20 +/- 1 N end load the nut mustnot cross thread. The tendency towards self alignment must not be prevented.2.2 DR IVE TEST. The
4、 nut must be driven on to the test piece with a 20 +/- 1 N maximum axial loaduntil a minimum of 3 full form threads of the test piece protrude through the nut.The torque required to drive the nut (Paint Clearing Torque) must be measured and must notexceed the values specified in Table 1.The test pie
5、ce must not be re-used.3. TEST PIECES.Test pieces must have ISO metric threads of tolerance class 6g. Thread length must be 2D minimumwhere D is the nominal diameter of the nut to be tested.The test piece must be grey electrocoated 25 to 30 micrometers thickness in accordance with WSK-M64J29-C1-C3 a
6、nd baked at 175 o C min., followed by primer surfacer 20 to 30 micrometers thickness inaccordance with WSK-M6J160-A1 baked at 165 oC min., and enamel paint 40 to 50 micrometersthickness in accordance with WSK-M50J111-A baked at 130 o C min.Baking time must be 10 minutes minimum, with the metal at he
7、at, for each process.Thicknesses as specified above must be measured on the head or plain shank of the test piece. the coatingin the threaded portion of the test piece must show uniformity on the sides and crests of the thread with athickness not exceeding 0.12 at the root of the thread.Table 1. Paint clearing torqueNominal Size Torque Max NM4 0.9M5 1.6M6 3M8 6M10 11M12 16
