Except for those greenhouses that are specially equipped by large-scale greenhouse manufacturers, plastic films purchased from the market generally have a diameter ranging from 1 to 5 meters. Generally, a large number of narrow films are required to be bonded into three or four blocks for covering greenhouses. Or a whole block, then cover it to the skeleton. The bonding method uses electric irons, electric irons, etc. for warming and sealing, and agent bonding methods may also be used. Hot-stick method. Prepare a flat, smooth, wooden strip 1.5 to 2 meters long, 5 to 6 centimeters wide, and 8 to 10 centimeters high as a backing plate. Attach a thin iron screen to the bench. In order to prevent the plastic from being damaged during the splicing process, the plane slats of the slats should be flattened to a more slick surface with a plane. One edge of the two films to be bonded is aligned on the wooden strips, overlapping each other by 4 to 5 centimeters, and operated by 3 to 4 people at the same time. People have put a piece of kraft paper or old newspapers with a width of 8 to 10 centimeters and a length of 1.2 to 1.5 meters at the well-seamed film. After the cover is covered, the preheated iron is used along the end of the wood strip, and the appropriate pressure is used. Push slowly to the other end. The heat of the iron used, the downward pressure, and the speed of advancement shall be softened and adhered to a certain degree after the two films under the paper are heated, and then the paper strips will be peeled off and will be glued. The film is pulled toward the other end of the strip and the next section is repeatedly bonded and reciprocated until the film is brought to the desired length. The temperature of the electric iron should be mastered when bonding the film, the suitable temperature for bonding the polyethylene film is 100-110°C, the PVC is 120-130°C, the temperature is low, the adhesiveness is not strong, and cracks easily occur afterwards. High, easy to melt the film, there will be holes in the seam or thin film. The pressure used and the moving speed of the electric iron must be matched with the temperature. When the temperature is high, the pressure used is smaller, the moving speed is faster, the pressure used when the temperature is low is large, and the moving speed is slowed down. When there are greasy marks on the pad, it means that the temperature is too high and the plastic has melted. At this time, the paper cannot be removed immediately. It should be cooled for a while. When the paper is not hot, it can be better. Ensure the quality of bonding. When the old film is to be branded, the film of the joint should be wiped cleanly, and the newspaper should be glued together with the film to a moderate standard, otherwise the joints will crack easily. Adhesive method. Perchlorethylene resin plastic adhesive can be used to repair and repair polyvinyl chloride film. Polyethylene film can be repaired with polyurethane adhesive. Sometimes it can also be hot-pressed with a small steel saw blade. Slurry sticking method. During the use of the greenhouse membrane, if there is a small damage such as hanging or wrinkle, a piece of plastic can be cut and the mud water can be stuck on the broken place.
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