DIN-557标准规范

UDC621.882.33January 1994Product grade C square nutsN557Vierkantmuttern;Produktklasse CSupersedes February 1985 edition.In keeping with current practice in standards published by the International Organization for Standardization (ISO),a comma has been used throughout as the decimal marker.The new widths across flats 16 mm and 18 mm as specified in ISO 272 shall be used instead of the previouswidths across flats 17 mm and 19 mm for thread sizes M 10 and M 12:see clause 4 for example of designation.It is intended to omit the obsolescent widths across flats by 1 January 1999 at the latestDimensions in mm1 Scope and field of applicationThis standard specifies requirements for M 10 to M 12 square nuts assigned to product grade C.See DIN 962(orthe standards referred to therein)for special nut types or finishes.If,in special cases,nuts are to comply with specifications other than those given in this standard (e.g.regardingproperty class or material),these shall be selected in accordance with the relevant standards.2 DimensionsCountersinkpermitted.15to309mw is the minimum wrenching height;for this zone,the minimum value of e shall be maintained.Table 1Thread size(d)M5M6M8M10M12M16P)0,811251,51,752dwmin.6,78,711.514.515.516,517,222max.11314118,422,62425.426.933.9min.9,9312.5316,3420,2421,5422,8424.0230,11max nominal size456.510m13min.3,524,525,927,429,4212,3mwmin.253,2415,26,68.6max.=nominal size810131617181924min.7.649.6412,5715.5716.5717.5718,4823,16Mass per 1000 units2),in kg1,312,775,510,71316,319,1382')P=Pitch of thread(coarse pitch thread).2)Approximate value,with o=7,85 kg/dm3Continued on pages 2 and 3.