... 2. including Casing head tubing spool gate valve flange 3. base on API 6A standard Oil drilling equipment parts including ... caseT/T, L/CWe supply a complete line of API 6A wellhead equipment including casing heads, casing spools, tubing ... tubing hangers, base plates, secondary seals, FC type slab gate valves, M type expanding gate valves, , flanges, adapter spools, spacer spools, , etc Inspection ...