Hazards of Incomplete Welding of Plastic-coated Steel Pipes and Installation of Construction Machinery

hazards of incomplete penetration of plastic-coated steel pipes:
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.

the following construction equipment should be used for plastic-coated steel pipes:
(1) the cutting should be cut with a metal saw;
(2) the pressure groove should adopt a special rolling groove machine;
(3) the pipe bend should be cold-formed by a pipe bender;
(4) the threading should be processed by an electric threading machine;
(5) the deburring of the end of the plastic-coated steel pipe and the processing of the corner should be processed with a file;
(6) a small brush or a small toothbrush should be used to apply high-strength inorganic solvent liquid epoxy resin coating.