... gas wellhead consisits of threaded flange,gate valve,studded cross ,adapter spoolNB:2-9/16" 3-1/16" etc wellhead ... head, casing spool,tubing spool,tubing head adapter,studded cross, threaded flanges,adapter spool,gate valve,choke valve and the tree ... and life ! B.rgdsYancheng Qihang Petroleum Machinery Co.,Ltd natural gas wellhead consisits of threaded flange,gate valve,studded cross ,adapter spool