(1) Before aligning the steel pipe, the heat shrinkable sleeve, together with the lining film or paper, is put on the steel pipe. According to the length of the heat shrinkable tube, the boundary line of the overlap area of the anticorrosive coating is drawn and moved to the position not affected by the welding work (usually about 1.5 m).
(2) When preheating, spray lamps, special spray guns and other heating devices should be used to preheat the anticorrosive pipe sections to 70-80 C, that is, the preheating temperature should be 10 C lower than the softening point temperature of hot melt adhesives. Hot melt stick can be used to check the preheating temperature. When the stick contacts the steel pipe, it will be scalded, indicating that the preheating temperature meets the requirements. It is absolutely forbidden to operate steel pipes without reaching the required temperature.
(3) When heating, attention should be paid to the overlap of the two ends of the heat shrinkage sleeve with the prefabricated coating of the steel tube not less than 50 mm, and the two ends of the heat shrinkage sleeve should be supported by short wooden wedges, so as to make it concentric with the pipeline.
(4) Heating should start from the center and move uniformly downward and downward along the diameter direction of the heat-shrinkable tube. It is strictly forbidden for the flame to move along the long axis or stay in one place. After the shrinkage of the heat shrinkage sleeve is basically completed, the hot melt glue overflows at the end of the sleeve after being heated completely and uniformly by micro-fire.
(5) The elbow can be constructed by overlapping heat-shrinkable pipes (shrimp-rice overlapping type). The overlapping part is not less than 50 mm. The heating method is the same as that of straight pipes.
Where to find heat shrink tubing
You can find the tube on our website: www.gzhelectric.com, www.khenterprise.en.alibaba.com