... Technology have 4 types: Pressure thread seal type, non-pressure thread seal type, integral type, and welded type ... sour environment according to the user needs. Pressure threaded seal end connection is consist of: FIG402 union ,FIG602union ,FIG1002union ... 28MPa(4000psi)and 105MPa(15000psi) •Non-pressure threaded seal end connection is consist of FIG206union ,FIG602union,FIG1002union,FIG1502union ...