The total amount of hot and cold water pipes inside the building should be determined through objective analysis of market demand, so that the supply and demand are basically balanced, and excessive excessive investment in the production of aluminum-plastic composite pipes is avoided.The traditionally used galvanized steel pipes will be phased out sooner or later, and the development of the indoor water supply pipe market is a historic opportunity to develop new pipes. But what is the total amount of this market, and how much aluminum-plastic composite pipe can account for? This should be analyzed and estimated.There is an estimation method that uses 2m of indoor water supply pipe per m of new residential building area. If the new residential building in China is 300 million m in 2000 according to the construction statistics of the Ministry of Construction, China completed the completion of urban new housing in 1996, with a total area of ​​34.27 million m, including residential 215.8 million . The total demand for indoor water supply pipes is 600 million。

Assuming that 30% use a variety of new plastic indoor water supply pipes, it needs 180 million meters. If the aluminum-plastic composite pipe can account for 30% to 50%, the market for aluminum-plastic composite pipes in 2000 is about 60 million to 90 million meters. Compared with Europe, which has long experience in the application of plastic water supply pipes, the application of 65 million m of aluminum-plastic composite pipes in 1997, if the amount of aluminum-plastic composite pipes in China reached or exceeded 60 million m in 2000, it would be a very welcome progress.This estimate is only for urban residential buildings. For large public buildings, it is estimated that copper pipes, stainless steel and other metal pipes are mainly used, and it is impossible to apply aluminum plastic pipes in large quantities. In addition, there are rural houses, and the newly built area is not less than 100 million meters per year. With the improvement of farmers' living standards, the application of pipes will gradually increase.

There is also a certain market for aluminum-plastic pipes in this respect, but a process is needed.However, it should be noted that there are still many companies preparing to invest in new aluminum-plastic composite pipes. Enterprises that have already produced aluminum-plastic composite pipes are also planning to expand production capacity most companies only have one production line at the start because aluminum-plastic composite pipes When the product specifications are replaced, the wastes that are debugged are greatly lost. It is suitable for one production line to produce one specification. Generally, aluminum-plastic composite pipe enterprises must have more than three production lines to operate economically. There are already more than a dozen machinery enterprises producing aluminum-plastic composite pipe production lines in China. If the trend is progressing, the enterprises producing aluminum-plastic composite pipes in China will face difficulties in sales in the next few years.

Based on the above findings, it is recommended that enterprises that have invested in aluminum-plastic composite pipes should improve the specifications and varieties of aluminum-plastic pipe products, produce matching pipe fittings, and cross-linked polyethylene-aluminum plastic pipes for hot water and heating; To improve the quality of pipe products, it is to improve the market competitiveness of aluminum-plastic pipes. It must be pointed out that the service life of plastic pipes is determined by the long-term (50-year) hydrostatic design basis value (HDB) of the hoop tensile strength of the pipe. Under the conditions that the polyethylene, adhesive, aluminum and other materials used in the manufacture of aluminum-plastic pipes are not stable enough, many people emphasize that the service life of aluminum-plastic pipes is 50 years or even 90 years, and the basis is not sufficient. It is recommended that qualified business units strengthen scientific experiments in this area. In addition, for the regions currently preparing to invest in new aluminum-plastic pipe production plants, it is recommended to make a decision on whether to invest and determine the scale of the plant construction under the conditions of correctly estimating the market situation in the region and implementing relatively stable market demand.