PE-RT pipe and PE-RT II type pipe should adopt two welding processes:
1. For PE-RT pipe hot melt socket welding process, two points should be paid attention to:
（1）. The temperature of the hot melt machine is controlled at 250-260°C;
（2）. PE-RT pipes and fittings should stay in the die for a short time and fast when they are inserted. When the pipes and fittings are pulled out again, the pipes and fittings should be inserted quickly at that moment. The normal operation process is to adjust the machine to 255°C and prepare the pe-rt pipe fittings to be hot-melted. When the temperature of the hot-melting machine reaches the set temperature, hold the pipe with the left hand and the right hand with the pipe fittings to balance and insert until the left and right hands. At the same time, when you feel that the pipe fitting has reached the socket depth, quickly pull the pipe fitting out of the die, and quickly insert the pipe into the pipe fitting for a certain period of time to cool down before letting go.
2. PE-RT pipe hot melt butt welding process
（1）. Fix the parts that need to be butted. Fix the PE-RT pipes and parts to be welded on the fixture of the welding machine. The center lines of the fixed pipes and parts should be on the same level, and the pipe walls should overlap to avoid heights, lows, and left and right. stagger.
（2）. Flatten the end face of PE-RT pipe. Before milling, use a clean cotton cloth to wipe clean the inside and outside of the pipe end within 100mm, then fix the milling cutter, and push the running part to mill the pipe end. There are two issues to pay attention to here. One is to slowly withdraw the force before stopping to ensure that the pipe end is smooth (a sudden withdrawal of the force will leave a groove shell on the pipe end), and the other is to prevent secondary pollution before the pipe end is heated.
（3）. Hot melt butt joint Before the heating plate melts the butt surface, check the matching condition again. If there are visible gaps or misalignment, adjust the tightening nut to correct it. First, preheat the heating plate of the hot-melt butt welder to 210～220℃, and then melt the end surface of the PE-RT pipe. The melting time is generally wall thickness × 10 seconds. It should be noted here that the temperature indication of the heating plate can only be used as a reference, and the indication may sometimes differ from the actual situation due to environmental temperature and its own quality. The hot melt meeting the design requirements mainly depends on the melting and crimping of the pipe end. The crimping thickness should not be less than 1/10 of the pipe wall thickness.
（4）. After the two hot-melt surfaces (PE-RT pipe and pe-rt pipe or PE-RT pipe and PE-RT pipe fittings) meet the welding requirements, quickly remove the heating plate and apply force to both ends Into one. After the force is applied, the lock should be locked immediately to maintain a constant butt pressure at the interface. The pressure cannot be released until the temperature of the interface drops to the ambient temperature, and the fixing device should be removed. No external force can act on the pipe. 5. After fixing the machine device, inspect the appearance of the fusion joint. The height and width of the hot fusion ring of the joint should be uniform and beautiful. Its height is 2～4mm, and the width is 4～8mm.
