Introduction to knowledge about anti-corrosion spiral steel pipes for water supply and drainage

The anti-corrosion spiral steel pipe for water supply and drainage is a layer of polyethylene (PE) resin, ethylene-acrylic acid copolymer (EAA), epoxy (EP) powder, and non-toxic polypropylene (PP) with a thickness of 0.5 to 1.0 mm melted on the inner wall of the steel pipe. Or steel-plastic composite pipes composed of organic matter such as non-toxic polyvinyl chloride (PVC). Plastic-coated steel pipes not only have the advantages of steel pipes such as strength, ease of connection, and resistance to water flow impact, but also overcome the shortcomings of steel pipes that are prone to corrosion, pollution, and scaling when exposed to water, as well as the low strength and poor fire-fighting performance of plastic pipes. The design life can reach 50 years.

The main disadvantage of anti-corrosion spiral steel pipes for water supply and drainage is that they must not be bent during installation. During thermal processing, electric welding, and cutting, the cutting surface should be painted with non-toxic room temperature curing glue supplied by the manufacturer. The main specifications are Φ15-Φ300. The main models of anti-corrosion spiral steel pipes for water supply and drainage are: GS--X-SP-T-EP, GS--SP-T-EP, GS--D-SP-T-EP (PE).

Plastic-coated steel pipes, also known as plastic-coated pipes, steel-plastic composite pipes, and plastic-coated composite steel pipes, are based on steel pipes. A layer of plastic anti-corrosion layer or plastic anti-corrosion layer is fused to the inner surface of the steel pipe (bottom pipe) through spraying, rolling, dipping, and suction processes. A steel-plastic composite steel pipe with a plastic anti-corrosion layer fused to the inner and outer surfaces. Anti-corrosion spiral steel pipes for water supply and drainage have excellent corrosion resistance and relatively small friction resistance. Epoxy resin-coated steel pipes are suitable for transportation water supply and drainage, seawater, warm water, oil, gas, and other media.

Cutting method of anti-corrosion spiral steel pipe for water supply and drainage:
1. Pipe cutting: Metal saws should be used for pipe cutting, and sawing machines should be used for large-diameter pipes. When using coil cutting, the rotation speed should not exceed 800r/min; the section of the pipe to be cut should be perpendicular to the axis of the pipe;
2. Preparation before pipe connection
①The metal burrs of the cut pipe port should be smoothed with a fine file;
② A special reamer should be used for water supply and drainage anti-corrosion spiral steel pipes to chamfer 1/2 of the thickness of the plastic coating layer, and the chamfering slope should be 10°-15°.
③ If the coating of the plastic-coated steel pipe is intact at the port, it should be chamfered with a sharpener; if the port is damaged, repair it (use repair fluid) until the coating is completely crack-free;
④ After rolling the groove, the plastic coating on the protruding part of the groove will be damaged, so it needs to be repaired until the coating surface is smooth and there are no cracks or damaged points;
⑤Cleaning processing should use cotton waste and brushes to remove oil, water, and metal cutting at the pipe end and inside the pipe.