International Organization for Standardization (ISO)
Latest
ISO 3419:1981
Scope
This second edition cancels and replaces the first edition (1975). Specifies the dimensions, tolerances and generally used grades of non-alloy, low alloy and alloy steels for bends /type 2D (90 and 180 ) and 3D (45 , 90 and 180 )/, concentric and eccentric reducers, tees, caps and ends with quality requirements as used for piping work.
ISO 3419:1981 history
1981ISO 3419:1981 Non-alloy and alloy steel butt-welding fittings