Hazards of incomplete penetration of plastic-coated steel pipes during welding

the hazard of incomplete penetration of the plastic-coated steel pipe is that the effective area of the weld is reduced, and the plastic-coated steel pipe reduces the joint strength.

secondly, the harm caused by the stress concentration caused by incomplete penetration is much greater than the harm caused by the decrease in strength. the incomplete penetration of the plastic-coated steel pipe seriously reduces the fatigue strength of the weld. incomplete penetration may become the source of cracks and is an important cause of weld damage. prevention of incomplete penetration: welding with higher current is the basic method to prevent incomplete penetration.

in addition, when welding fillet welds on plastic-coated steel pipes, use ac instead of direct current to prevent magnetic deflection blowing, rationally design grooves on plastic-coated steel pipes and strengthen cleaning, and measures such as short-arc welding can also effectively prevent incomplete penetration.