... oil drilling equipment- christmas tree consists of the casing head,tubing head and christmas tree.The main technical ... line of API 6A wellhead equipment including casing heads, casing spools, tubing heads/spools, tubing head adapters, casing hangers, tubing hangers, base plates, ... valves, DM type mud gate valves, flanges, adapter spools, spacer spools, and H2 type chokes, etc Inspection Test Pass ...