1. Their base materials are different. Steel-plastic composite pipes use steel pipes as the base material and are later coated into a plastic material, which retains the characteristics of the steel pipe and has very high-pressure resistance and impact resistance. Compared with traditional cast iron pipes, it is economical, environmentally friendly, safe, and reliable. Plastic-lined steel pipes are made of steel pipes and plastic pipes, which are pressed together under high pressure and high temperature. They are safe and hygienic, and the thickness of the inner wall has also been increased, making them less prone to corrosion problems.
2. In terms of their installation, plastic-lined steel pipes use ring-pressed connections, so the workload during installation is relatively large, the joints are prone to rust and water seepage, and the cost of later maintenance is also high, it is easy to cause water pollution. Relatively speaking, steel-plastic composite pipes can effectively avoid similar problems.

As improved versions of drinking water pipes, plastic-lined steel pipes and steel-plastic composite pipes are not much different in terms of mechanical strength, pressure-bearing performance, and service life, and their advantages are also very similar. However, they are two different pipe materials after all, so, differentiate carefully, there is still a difference.
1. The main difference between the two is the environmental protection performance. The main material of plastic-lined steel pipes is epoxy resin powder. This powder contains certain toxic and harmful substances. If used as water supply pipes, it will bring certain dangers to drinking water pipes and directly affect human health. However, steel-plastic composite pipes use composite pipes, which are non-toxic and will not cause pollution to the environment.
2. Another difference is the different usage environment. The interior of the plastic-lined steel pipe is uneven and somewhat rough, which makes it easy to accumulate scale and breed bacteria. When used in hot water pipes, it is susceptible to thermal expansion and contraction, which will affect its service life. The inner wall of the steel-plastic composite pipe is smooth and not prone to dirt, so it can be used not only in cold water pipes but also in hot water pipes.
3. There are differences in prices. In comparison, the price of steel-plastic composite pipes is slightly cheaper, mainly because the workmanship of plastic-lined steel pipes is more complicated, the cost is higher, and the price is more expensive.

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