Flared fittings andInsert Welded pipe joints

Using flaring tube ends are sealed, no additional seals. Simple structure, suitable for thin-walled pipe coupling for oil and gas as a medium low pressure pipeline system, which allows the use of pressure are shown in Table 41 Table 27 ~ 41GB5625.1 ~ 5653-1985
Insert Welded pipe joints
Will require the length of the tube into fitting until the pipe end in contact with the inner end of tube hydraulic hose sleeve  tube and pipe joints will be welded into one, eliminating the need to take over, but require strict application of pipe size to oil, gas pipeline system for the medium Table 43 ~ 49JB3878-1985