ASME B16.42 pdf download Ductile Iron Pipe Flanges and Flanged Fittings Classes 150 and 300 6 MATERIALS 6.1 Castings Ductile iron castings covered by this Standard shallconform to ASTM A395.The castings shall not berepaired byplugging， welding, brazing, orimpregnation. 6.2 Bolting Bolting listed in paras. 6.21 and 6.22 is recommendedto be used in flanged joints covered by this Standard.Bolting of other...