FORDWORLDWIDEFASTENERSTANDARD

Date:1996-07-01

WB900

GeneralandDimensionalRequirementsofPanHead,RaisedCountersunkHeadandFlatCountersunkHead

MachineScrews,andMachineScrewandToothWasherAssemblies

1.SCOPE.

Thisstandardspecifiesthegeneralanddimensionalrequirementsofpanhead,raisedcountersunkhead

andflatcountersunkheadmachinescrewsandmachinescrewandmachinescrewandtoothlockwasher

assemblieswithrecessdrivesystems.CrossrecessdataisshowninAppendixA.Lobedrecessdatais

showninAppendixD.

2.REFERENCES.

ISO261-ISOGeneralpurposemetricscrewthreads-Generalplan.

ISO965-ISOGeneralpurposemetricscrewthreads-Tolerance.

ISO1502-ISOGeneralpurposemetricscrewthreads-Gauging.

ISO4762-Hexagonsocketheadcapscrews-ProductgradeA.

ISO7721-Countersunkheadscrews-Headconfigurationandgauging.

WA900-Dimensionalrequirementsforhexagonandflangedhexagonboltsandscrews,and

hexagonscrewandwasherassemblies.

WA990-Surfacediscontinuitiesofboltsandscrews.

3.GENERALREQUIREMENTS.

3.1DIMENSIONSANDTOLERANCES.Thedimensionsandtolerancesofpanhead,raised

countersunkheadandflatcountersunkheadmachinescrews,andmachinescrewandtoothlock

washerassembliesshallbeinaccordancewithClauses1-8,Tables1-4andFigures1-4.

3.2WASHERS.Thedimensions,tolerancesandmaterialsrequirementsofthewashercomponentof

machinescrewandtoothlockwasher