Characteristics and differences between steel-plastic composite pipe and plastic-lined steel pipe

Whether in home improvement or construction projects, many plates and pipes are concepts that we "amateurs" can't distinguish, and of course we can't figure out their respective performances. Then, let's take steel-plastic composite pipe and plastic-lined steel pipe as examples today to talk about their respective characteristics and differences.

Conceptually, steel-plastic composite pipe and plastic-lined steel pipe;

Steel-plastic composite pipe is a thermoplastic plastic pipe with excellent chemical stability based on ordinary carbon steel pipe. After cold-drawing composite or rotational molding, it not only has the mechanical properties of steel pipe, but also has the characteristics of corrosion resistance, difficult scaling and difficult microbial growth of plastic pipe. It is an ideal pipeline for conveying media such as acid, alkali, salt and corrosive gas.

Plastic-lined steel pipe, also known as steel-plastic composite pipe, is based on galvanized seamless steel pipe and welded steel pipe. After the weld is removed from the inner wall, the food-grade polyethylene (PE) pipe with the same diameter as the galvanized pipe is lined. The thickness of the polyethylene lining conforms to CJ/T 136-2007 standard, and finally it is heated under pressure for a certain period of time and then molded. It is an upgraded product of traditional galvanized pipe.

Characteristics of steel-plastic composite pipe and plastic-lined steel pipe;

Characteristics of steel-plastic composite pipe: because the basic materials of steel pipe are seamless steel pipe and welded steel pipe, the rigidity and strength are good; The inner wall of steel-plastic composite pipe is smooth and will not scale; Then, the impact resistance is strong, the weight is light, and the environmental temperature basically does not affect its contraction or expansion, which is safer.

Characteristics of plastic-lined steel pipe: wide application range and complete specifications; The production process is unique, and the connection mode is reliable and fast; The external surface anticorrosion measures are perfect, and the wall thickness of welded pipe is reasonable. It's just that the installation is time-consuming and laborious, and the cost is relatively high, which can't completely solve the water pollution at the joint of pipe fittings. This is the shortage of plastic-lined steel pipes.

The difference between steel-plastic composite pipe and plastic-lined steel pipe;

The similarity between steel-plastic composite pipe and plastic-lined steel pipe is that the mechanical strength, pressure-bearing performance and service life are almost the same. But after all, they are two different pipes, so there are natural differences.

From the point of view of pollution: the inner layer of steel-plastic composite pipe is pollution-free; The inner layer of plastic-lined steel pipe is mainly made of epoxy resin powder or pe powder, which contains harmful components and is harmful to human body.

Judging from the smoothness of the inner wall, the steel-plastic composite pipe is smooth and not easy to scale, and can be used in both cold water and hot water. However, the inner wall of plastic-lined steel pipe is not smooth and easy to scale, so it will expand when used in hot water system.

From the price point of view: steel-plastic composite pipe is slightly more affordable than plastic-lined steel pipe because of its workmanship.

In short, the characteristics of steel-plastic composite pipe or plastic-lined steel pipe are different, so there are some differences between them, but in any case, these two pipes are quite excellent drinking water pipes. How to choose depends on your own preferences and the specific environment you use.