Geomembrane is a kind of waterproof and barrier material based on polymer. It is mainly divided into: low density polyethylene (LDPE) geomembrane, high density polyethylene (HDPE) geomembrane and EVA geomembrane. It has excellent resistance to environmental stress cracking and chemical corrosion. It is suitable for landfill, tailings storage field, canal seepage control, Dike Seepage Control and subway engineering.
Construction procedures and process requirements of geomembrane double seam heat sealing welding machine:
1. When the ambient temperature is higher than 40 ℃ or lower than 0 ℃, the geomembrane cannot be welded.
2. Preparation before construction: preparation before formal welding, inspection of lap width after film laying: lap length of HDPE film welding joint is 80-100 mm.
3. Before welding, the film surface within the scope of about 200 mm of lap joint shall be cleaned, and the dust and dirt shall be wiped off with wet cloth to keep this part clean and dry.
4. There shall be no scratch, stain, moisture, dust and other impurities that hinder the welding and affect the construction quality.
5. Before the formal welding operation, the equipment parameters shall be set according to the experience, and the small film of 300 × 600mm shall be taken for test welding. Then, the shear and peel test of the weld is carried out on the tensile machine. If it is not lower than the specified value, the parameters will be locked and the formal welding will be started based on this. Otherwise, the parameters should be determined again until the test is qualified. When the temperature and wind speed change greatly, the parameters should be adjusted in time and the test should be repeated to ensure that the welding machine performance, site conditions and product quality meet the requirements of the specification. The evaluation criteria for the success or failure of the test welding are as follows: the film can only be torn and the weld joint can not be damaged when the welding seam is sheared and peeled.
6. The distance between the horizontal joint and the slope toe and the place with high pressure should be less than 1.5m.