How do you connect HDPE Liner
For HDPE geomembrane connection methods, we introduce our welding method: the hot welding method. The hot welding method is the surface heating treatment of the PE geomembrane so that the surface is melted, and then the geomembrane is fused into a whole through pressure, and the geomembrane is laid along a certain direction.
Firstly is the preparations before welding :
1.we should prepare the materials and tools we need:1.0~3.0mm HDPE geomembrane(1800w welding machine can not weld less than 1mm), we should choose the right thickness for your welding machine), 1800W welding machine, extrusion welder machine, hot air gun, polishing machine, pressure gun, and some welders.
2.Lay the two pieces of the geomembrane on the flat access which is free of sharp stones and other wastes, pls do not put it on the welding area on the slope, because welding on the slope is not easy and is not as hard as that on the flat access.
3.Connect the welding machine to the voltage:220V(frequency 50/60HZ) power, then adjust the pressure of the welding machine and preheat the welding machine to 300 degrees.
4.Do the wiping treatment of the overlap of the geomembrane. Wipeout all the waste from the geomembrane, such as the stones, the sands, and dust, to keep the surface of the overlap clean and dry. Please keep in mind that the overlap width should be 10cm–15cm. Do not be less than 10 cm.
Then we can start the welding, before the formal welding, we should do a welding test to see if the welding requirements qualified. Cut one piece off the HDPE geomembrane that is the same as the geomembrane you want to connect, the testing welding size should be 0.9mm X 0.3mm, the overlap should be less than 10 cm. Then we can do the sample test, such as using the tensile machine on-site for stripping and shear test. If the sample qualified, then we can continue the formal welding. We can adjust the speed, pressure, temperature a little when welding .we mark the date, time, and ambient temperature on the sample. In the welding process of a hot welder, it is necessary to pay attention to the operation of the welder at any time, and fine-tune the speed and temperature according to the actual situation on site.
If the length of the geomembrane is not enough, pls choose “T”-shape welding methods. Please take the following precautions in this stage: Cut off the excess geomembrane; Weld T-shape with extrusion welder machine. Then cut a circular geomembrane that can completely cover the T-shaped area. Weld the T-Shaped area with a hot air gun. Then polish the T-shaped area with the polishing machine.
Do the pressure test, at last, can see if the welding is qualified
1. Insert the pressure gun head into the sealing hollow between the two ends of the welding area.
2. Raising the air pressure to test the air pressure which is close to the value(the air pressure testing depends on the thickness of the geomembrane you use), record the pressure data.
3. Record the pressure after 5 minutes for the second time
4. Compare the two data of the air pressure values, if the changes of the two data less than 5%, the welding will be qualified。
If you have any questions about the welding and installation of geomembrane, you can contact me. We will provide you with free geomembrane welding and installation training.
Earth Shield Environmental Co., Ltd.
WhatsApp : +86 189 6341 6260