Application Areas of Common Large-Diameter Plastic-Coated Steel Pipes

Large-diameter plastic-coated steel pipes primarily use spiral steel pipes or seamless steel pipes as the base material. Straight seam welded pipes are not recommended, as their pressure resistance is generally inferior to spiral steel pipes, and their cost is higher. Therefore, spiral steel pipes are preferred as the base material for large-diameter plastic-coated steel pipes; seamless steel pipes are used only when higher pressure requirements are needed.

Large-diameter plastic-coated steel pipes are mainly used in HVAC, municipal, industrial, and sewage systems. In HVAC and municipal applications, large-diameter plastic-coated steel pipes address the problems of rust, scaling, and contamination inherent in ordinary steel pipes. Furthermore, the service life of large-diameter plastic-coated steel pipes is 5-10 times longer than that of normal steel pipes, significantly reducing maintenance costs after pre-installation and embedding, as well as the cost of replacement after the pipes reach the end of their service life.

In industrial and sewage treatment sectors, the substances discharged or transported typically have a certain acidity or alkalinity. Under long-term oxidation, the corrosion rate of steel pipes is often dozens of times faster than normal. Large-diameter steel pipes are already very expensive, and rapid corrosion causes costs to skyrocket. This results in a net loss compared to the desired performance. Using large-diameter plastic-coated steel pipes, however, does not reduce the pipe’s pressure resistance, and reduces its susceptibility to acid and alkaline corrosion and long-term oxidation in the air to almost zero.

Therefore, the service life of the pipe is increased from a few years to several decades. The service life is increased tenfold, while the cost remains roughly the same.

Large-diameter plastic-coated steel pipes have won widespread popularity in HVAC, municipal, industrial, and sewage treatment industries due to their superior performance, high cost-effectiveness, energy saving, environmental protection, and ease of cleaning and maintenance.