For overhead pipeline, welding with basic-compound coated electrodes and pre-weldingheating of the joint will reduce the joint thermal -stress.
采用碱性药皮焊条和焊前接头预热的施焊方法，焊接的空间管道接头热应力小。
2
Localized heating from the welding process and subsequent rapid cooling induces welding shrinkage stresses along weld bead during welding thin-wall plate and causes structural buckling distortions.
在薄板焊接中，由于局部加热和迅速冷却产生了沿焊缝方向的焊接收缩应力，而导致焊接薄板发生屈曲变形。
3
A welder's kit contains electrode holder, welding torch, helmet shield, portable electrode heating box and temperature measuring pen.