How to compile the welding technology of 12CrlMoVG header and pipe joint
(2) before welding, before welding, the pipe should be 30 degrees, and the inside and outside 15mm range of the pipe should be polished to be metallic. The pipe clearance is 1~3mm. When the actual clearance is too large, the transition layer shall be deposited on the side of the pipe groove. Set up temporary shelter facilities, strictly control the wind speed at the welding operation place, and the air hole is easy to generate because the wind speed is beyond a certain range.(3) the operation uses WST315 manual tungsten argon arc welding machine, the welder itself is equipped with high frequency arc striking device, and the high frequency arc striking can be adopted. The arc and arc electrode, such as arc too fast, easy to produce crater crack, so the operation will lead to the edge of the pool or parent material is thick, and then gradually reduced the pool slowly extinguish arc, and finally close the protective gas.
1 welding method argon arc welding wire H08CrMoG.2, process:(1) welding example, economizer, evaporator section, tube bundle, water wall and low temperature superheater are made of No. 20 steel, and high temperature superheater tube is 12Cr1MoV.
The No. 20 steel pipe wall thickness 3~4mm, filling material available TIGJ50 (for 12Cr1 MoV, available 08CrMoV), tungsten rod diameter 2mm, 75~100A welding current and arc voltage of 12~14V, gas flow 8~10L/min, power supply for dc.
