Multi-Layer Pipes Will Be The Application Area Of Recycled Materials

Plastic pipes are widely used in urban and building water supply and drainage projects, power and communication projects, gas transmission projects, agricultural irrigation projects, industrial production and other fields. In recent years, with the promotion of urbanization and the expansion of plastic pipe application fields in China, the demand for infrastructure has increased, and the production of plastic pipes in China has achieved rapid growth.

From 2011 to 2018, the production of plastic pipes in China increased from 10 million tons to 15.67 million tons, with an average annual growth rate of 6.63%. Public information shows that the overall domestic production capacity of plastic pipes has exceeded 30 million tons. The industry has more than 3,000 large producers, of which less than 30 have an annual capacity of more than 300,000 tons. And the proportion of capacity of large enterprises is relatively small.

At present, plastic pipes have a market share of more than 50% of all types of pipes in the country. Among them, PVC pipe production is the dominant product, accounting for about half of the total output of plastic pipes; polyethylene and polypropylene pipes are relatively small, with polyethylene pipes accounting for about 30% of the total output of plastic pipes and polypropylene pipes accounting for about 10% of the total output.

Rigid polyvinyl chloride (PVC-U) water and drainage pipe is the best developed plastic pipe in China. It uses PVC resin as the main raw material and adds the necessary additives (including heat stabilizers, processing aids, lubricants, etc.) to process and form the pipe system. Two main types of connections are used: special glue joints and rubber ring flare sockets.

Polyethylene water and gas piping emerged in the late 1980s as a development of materials specifically for high-density polyethylene (HDPE) pressure piping. The long-term pressure resistance of polyethylene materials is improved by the addition of copolymer monomers such as butene and hexene during the polymerization process. the main types of PE pipe connections are hot-fusion socket, hot-fusion butt and electrofusion connections.

PP-R pipe is a random polymerization PP-R obtained by adding no more than 2% of ethylene monomer and propylene to the random copolymerization of PP raw materials in the preparation process, which improves the low temperature brittleness of ordinary PP and increases the long-term water pressure strength and high temperature resistance of the product.

Aluminum-plastic composite tube is a composite tube of metal and plastic. The inner and outer side is a plastic layer, the middle is an aluminum layer, and the middle is bonded with a layer of hot melt adhesive. The connection of aluminum-plastic pipes is usually made of copper parts.

Double-wall corrugated pipes and winding pipes are also the more developed varieties of plastic pipes in China. They are structural wall pipes, which differ from ordinary solid wall pipes in the presence of inner and outer wall structures. They are mainly used for buried drainage or communication pipes and can be larger than 3m in diameter.

The inner wall is smooth structure to meet the needs of fluid transportation, and the outer wall is corrugated or hollow structure to meet the needs of buried resistance to external pressure. Structural wall pipe saves raw materials while meeting the requirements of use. Compared with the same solid wall pipe, structural wall pipe can save 30%-50% of raw material. The raw material can be PVC or HDPE. the connection mainly includes rubber ring sealing connection, heat shrink band welding, etc.

In addition to the above plastic tubing, some other plastic tubing includes sheathing tubing for power transmission and chlorinated polyvinyl chloride (PVC-C), acrylonitrile-butadiene-styrene copolymer (ABS) for chemical applications.) Polyethylene tubing and HDPE silicon core tubing for fiber optics and communications jacketing, polyphthalamide tubing for the automotive, mechanical and pneumatic industries, cross-linked polyethylene (PE-X) tubing for floor heating, polybutylene (PB) tubing and heat resistant PERT tubing.

The European Plastic Pipe Manufacturers Association (TEPPFA) has committed to using 250,000 tons of recycled material per year by 2020. The European sponsorship program may require the use of recycled materials to replace more raw materials in the near future.

Currently, some pipeline recycled materials are used for non-pipelines and some non-pressure pipelines, and recycled materials are still not allowed for all pressure piping systems. One possible application area for recycled materials is multi-layer piping systems. Coextruded multilayer piping using partially recycled materials has similar durability to conventional piping.

Modified materials and new materials will emerge more quickly in the process of upgrading new products for plastic pipes. Gradually, there will be a shift from single material processing to modified composite materials to improve certain characteristics or comprehensive performance of pipes. Meanwhile, advanced engineering installation technologies such as trenchless technology, underwater laying technology, sand-free laying technology and large diameter pipe connection technology will be widely adopted.

JIANGSU ACERETECH Machinery Co., Ltd. is a professional manufacturer of plastic recycling equipment. For the waste plastic pipes produced in the plastic pipe production process, ACERETECH has developed and produced shredders for large diameter pipe recycling and shredders for small diameter pipe recycling (including post-recycling pelletizing equipment). ACERETECH will provide you with customized solutions for shredding, crushing and pelletizing.