After final forging/forming and Heat treatment process, all the pipe Fittings, Flanges, Fasteners, Etc. are sent for machining i.e. and preparation, O/D and I/D matching as per dimensional codes. An Expert Q.C. engineer is involved and he keeps constant vigil on every machining operation. Step machining is carried out as required by the codes. GO and NO-GO gauges are used to check the O/D & I/D of the fittings, Flanges, etc.