Polyvinyl chloride (PVC) piping system has a history of development for nearly 70 years, because of its high modulus, high strength and low price, it has been the most widely used plastic piping system in the world. However, there was a period of time when the performance level of PVC piping systems did not improve much, and the growth rate in some countries and application areas slowed down.

Although my country's PVC pipeline system has formed a huge scale with an annual output of more than 1 million tons, it has always stayed within the scope of traditional PVC-U. Many enterprises do not understand the trend and progress of international PVC pipeline technological innovation, because of technological progress. Slowness restricts further promotion and application.

　　
Internationally, it is constantly exploring to improve the performance level of PVC pipeline system and broaden the application field of PVC pipeline system, and has achieved remarkable results in the past ten years.

The main directions are:

1. Improve toughness through modification, and develop various modified PVC pipe systems with good impact resistance and crack resistance while maintaining high strength, usually called PVC-M or PVC-A or PVC-HI.

2. Through biaxial stretching in the process of pipe processing, the molecules are oriented, which can greatly improve the strength and increase the toughness. Often referred to as PVC-O or BO-PVC.

3. Expand the application field, such as: by improving the modification, the PVC pipe can be bent, folded, and even butt welded. Liner pipe for use in trenchless repair of old pipes.

The changes and development of the international situation in recent years have provided an unprecedented historical opportunity for the development of PVC piping systems in my country. In many application fields and high-speed mixer manufacturers' pipeline systems, the polyolefin pipeline system in the competitive market has been seriously affected by the explosion of oil prices, while the polyvinyl chloride, which can use coal as a raw material, has been maintained at a lower price to enhance its competitiveness. In the face of new market opportunities, if we can speed up innovation and development and keep pace with the technological progress of PVC piping systems in the world, we can open up a new situation.