HDPE Impervious Geomembrane Sewage Tank Impervious Construction Procedure – Ⅰ
Firstly. Basic requirements for anti-seepage chemical and anti-corrosion projects in sewage ponds
1. Chemical sewage tanks are mostly mixed-territory structures, and their surfaces are relatively flat. You only need to pay attention to cleaning debris such as rubble, stones, steel bars, and glass chips in the tank.
2. The shadows at the corners of the yin and yang on the base surface transition smoothly, and the root of the column should be made into an arc shape.
3. After the civil engineering, supervision, owner, and construction party accept the signature and approval, they can start the wholesale textured geomembrane construction.
Second. Climate requirements for HDPE anti-seepage geomembrane construction
1. The air temperature should generally be above 5 degrees Celsius, the geomembrane should be tight at low temperatures, and the geomembrane should be relaxed at high temperatures.
2. The wind is below level 4.
3. When the temperature is too low, the wind and rain or snow weather above level 4 should generally not be used for construction.
4. In windy weather, when the wind affects the construction of the wholesale LDPE geomembrane, the HDPE geomembrane to be welded should be compacted with large stones or sandbags.
Third. the laying of HDPE anti-seepage geomembrane
Laying HDPE impermeable membrane is a more critical process in the entire impermeable system. Before the film is laid, the appearance quality of the HDPE barrier film is opened for inspection, and the mechanical damage and production trauma, holes, breakage and other defects that have been found are recorded and repaired. Before cutting the HDPE impervious film, measure its relevant dimensions, and then cut according to the actual situation. During the film laying, the overlap width of the seam between the film and the film is not less than 100mm, so that the direction of the seam arrangement is parallel to the maximum slope line. That is, arranged along the slope direction. When laying the HDPE barrier film, the welds should be minimized, and the raw materials should be saved as much as possible while ensuring the quality. It is also easy to guarantee quality.
Usually, in the corners and deformed sections, the length of the joints should be as short as possible. Except for special requirements, as long as there is no welding seam on slopes with a slope greater than 1: 6 within 1.5 meters from the top slope or stress concentration area. HDPE impervious membrane should avoid artificial wrinkles during laying. When the temperature is low, it should be tightened and spread as far as possible.
After laying the HDPE barrier film, you should minimize walking on the film surface, moving tools, etc. Any object that can cause damage to the HDPE film should not be placed on the film or carried on the film to avoid causing damage to the film. Accidental damage.
Fourth. Welding of HDPE Impervious Geomembrane
HDPE impervious film is welded using a wedge welding machine, using dual-track hot-melt welding. A wedge welding machine can not be welded parts, should use an extrusion hot-melt welding machine, with the same quality electrode and raw materials to form a single welding seam.
1. The welding process of the hot head welding machine is divided into adjusting the pressure, setting the temperature, setting the speed, checking the weld overlap, installing the film into the machine, and starting the motor.
2. There should be no oil and dust at the joints, and there should be no debris such as sand, dew, moisture, etc. in the overlapped section of the HDPE barrier membrane. When there is debris, it must be cleaned before welding.
3. At the beginning of welding every day, usually a test specimen of 0.9mm × 0.3mm should be welded at the scene first, the overlap width should be no less than 10cm, and the peeling and shear tests should be performed on-site. After the specimen is qualified, it can be adjusted at that time. Good speed, pressure, and temperature are just welding. During the welding process of the hot head welding machine, it is necessary to pay attention to the operation of the welding machine at any time and to fine-tune the speed and temperature according to the actual situation on site.
4. Welds are required to be neat and beautiful, and there should be no slip welding or skipping.
5. When the length of the environmental geomembrane factory price is not enough, long-term splicing is required. Weld the transverse welds first, and then weld the longitudinal seams. The distance between the transverse welds should be T-shaped if the distance is greater than 50cm. Do not cross.
6. Dead folds are not allowed when welding the film. When laying HDPE geomembrane, the amount of expansion and contraction caused by temperature change is reserved according to the local temperature change range and HDPE geomembrane performance requirements.
7. Welding cannot be carried out during rain or when the joints have moisture, dew, or heavy sand, except for protective measures.
8. When the temperature is lower than 5 ℃, construction should not be performed according to the requirements of the specification. If construction is necessary, the welding machine should be pre-heat treated before welding.
9. HDPE anti-seepage geomembrane should be powered by a generator with good voltage stabilization performance when welding. In special cases, when using local power, a voltage regulator must be used.