Steel Plastic Composite Pipe

The steel-plastic composite pipe is a product based on a steel pipe and coated with a plastic anti-corrosion layer on its inner and outer surfaces or inner and outer surfaces. It is also called composite plastic steel pipe.

Steel-plastic composite pipes are made of seamless steel pipes and welded steel pipes. The inner wall is painted with high adhesion, anti-corrosion, food-grade hygienic polyethylene powder coating or epoxy resin coating. The galvanized inner-coated plastic composite steel pipe for water supply is made through pretreatment, preheating, inner coating, leveling, post-treatment and other processes. It is an upgraded product of the traditional galvanized pipe. Steel-plastic composite pipes are generally connected by threads, grooves, and flanges.

The advantages of steel-plastic composite pipe:

1.Excellent Corrosion Resistance 

With strong adhesive force, excellent compactness and sound resistance to corrosion, the inner plastic layer of the steel-plastic composite pipe can effectively prolongs the lifetime of the pipe. In general circumstances, the galvanizing coat is effectively resistant to the corrosion. But, under a bad working environment such as an acid environment the steel-plastic composite pipe is much better than the hot dip galvanized pipe.

1.Excellent Mechanical Strength 

With an excellent mechanical strength as the one of the hot-dip galvanizing steel pipe, the steel-plastic composite pipe can effectively bear such outside influences as impact, bending, pressure, etc.

2.Good Sanitary Property

Made of polythene or epoxy resin powder, the plastic layer is nonpoisonous, tasteless, causing no pollution to water, perfectly up to the state standards for the domestic water conduit pipe.

4.Small Fluid Resistance 

With a smooth inner wall and small friction, the steel-plastic composite pipe for water supply is hard to accumulate waterscale and has small fluid resistance, never blocks the water flow.

Application of steel-plastic composite pipe

1. Various forms of circulating water systems (civil circulating water, industrial circulating water), excellent performance, anti-corrosion life up to 50 years.

2. Fire water supply system.

3. Water supply and drainage transportation of various buildings (especially suitable for cold and hot water systems in hotels, hotels, and high-end residential areas).

4. Various chemical fluid transportation (acid, alkali, salt corrosion).

5. Buried pipes and passing pipes for wires and cables.

6. Ventilation pipes, water supply and drainage pipes of mines and mines.

The steel-plastic composite pipe is extensively applied to the civil water supply, industrial water supply, fire fighting, sewage transportation, communication circuit, optical fiber cable, coal gas transportation, foodstuff process, medicine and machinery fields, especially an ideal product for the urban water supply.

Steel-plastic composite pipe Chinese, British, American and Japanese national standards：

Chinese standard:

GB/T 28897-2021 "Steel-plastic composite pipes and fittings for fluid transportation"

American standard:

ASTM F2880, a standard developed by the American Society for Testing and Materials (ASTM), specifies dimensional, quality, and performance requirements for steel-plastic composite pipe and fittings. This is a comprehensive standard, including the material, manufacturing process, test method, marking and other content of the pipe fittings, which is a relatively common standard in the world.

British Standard:

BS 6920-1:2014, this standard mainly covers the applicability of non-metallic products in contact with human drinking water, including steel-plastic composite pipes, etc., to ensure that these products will not have adverse effects on water quality.

Japanese standard:

JIS K 6741-1999, this standard specifies the requirements for unplasticized polyvinyl chloride (PVC-U) pipe fittings, including steel-plastic composite pipes. The JIS K 6741-1999 standard covers the dimensions, physical properties, chemical resistance and other requirements of pipe fittings to ensure that the quality and performance of products meet the requirements of Japan.

This document specifies the classification and code, order content, size, weight and tolerance, technical requirements, test methods, inspection rules, packaging, marking, quality certificate, transportation and storage of steel-plastic composite pipes and pipe fittings for fluid transportation.

The size of the steel-plastic composite pipe varies according to the specifications
The specification is 15*1.8mm, the outer diameter is 20.5mm, and the wall thickness is 1.8mm;
The specification is 15*2mm, the outer diameter is 20.8mm, and the tube wall thickness is 2mm;
The specifications can reach 150*4.5mm, the outer diameter can reach 165mm, and the wall thickness is 4.5mm.