... ASTM and ANSI Standard and the technology indexes conform to API Spec 6A, the product adopts some end connections of pipeline ... Machinery Co.,Ltd specialize in API 6A products as following:1) Wellheads (casing/tubing head, crosses ,flange adapter,etc)2) Valve (FC ... /FLS gate valve, mud gate valve, chock valve, etc)3) Fitting(union, manifold,elbows), bop. API 6A ...