The docking or welding operations required for the use of PE pipes are commonly used nowadays,but why can some construction effects maintain stable use for a long time,while others have a relatively short duration?This is still due to the significant differences in the operational steps used for PE pipe butt welding,resulting in variations.
Firstly,the preparation work before welding PE pipes requires checking whether the welding machine meets the working requirements.According to the specifications of the pipes or fittings,appropriate fixtures are selected to clamp the pipes and place them in the frame clamp,so that the extension lengths of the two ends of the joint are roughly equal.If milling and heating requirements need to be met,the PE pipes should be shortened as much as possible.Usually,2530mm PE pipes are supported by a support frame outside the frame,so that the pipe axis is at the same height as the middle line of the frame,and then the clamp is fixed.
The cutting work requires inserting a milling cutter,then closing the welded ends of the two pipes,and applying appropriate pressure until both ends have continuous cutting.The cutting thickness is 0.5-1.0mm to ensure that impurities and oxide layers on the end face of the welded pipe section are removed,and to ensure that the two mating end faces are flat and smooth.The cutting thickness can be adjusted by adjusting the height of the milling cutter.
And the smaller the misalignment of the two welded pipes,the better.If the misalignment is large,it will cause stress concentration.The misalignment should not exceed 10%of the wall thickness.The displacement at both ends of the pipe should not exceed the larger value of 10%of the wall thickness or 1mm.By adjusting the straightness and tightness of the pipe,it can be corrected to a certain level;When closing,there should be no obvious gap between the two ends of the pipe,and the width of the gap should not exceed:0.3mmdn<225mm,0.5mm,225mm,400mm.If the above requirements are met,it should be milled again until the above requirements are met.Heating:After the temperature of the heating plate reaches the set value,place it in the rack and apply pressure until the small curled edges on both sides reach the specified width,and the pressure decreases to the specified value.
The PE pipe reduces the pressure to the specified value and continues to heat for the specified time.When welding pipes with different wall thicknesses,it is necessary to heat the pipe with the same wall thickness first,and then heat the pipe with the thinner wall thickness.
Because the size of PE pipes is relatively long after production,it is necessary to cut them appropriately according to the specific details of construction to make their use more in line with construction requirements.Therefore,the operation steps of butt welding also need to be carefully understood by everyone.