Construction to the (row) pipes are mainly random copolymer polypropylene ppr pipe, polyethylene (PE) pipe, to the (row) water with a hard polyvinyl chloride pipe three categories. PVC pipe has been widely used in construction to the drainage area; PPR pipe developed rapidly in recent years, mainly for the construction of transportation and other areas with hot and cold water; PE pipe as a new type of building materials is being vigorously promote the use of. A total of 50 batches of the product sample, after examination, qualified 47 batches, with a pass rate of 94%.

The detection of three batches of product failure, in which two batches of water with polyethylene (PE) pipe, the main failure items are: hydrostatic strength, oxidation induction time. Oxidation induction time (OIT) is to measure the oxygen at high temperature under the conditions of the specimen started to occur in autocatalytic oxidation of time, the evaluation material in molding processing, storage, welding and the use of thermal degradation of skills. Oxidation induction time shorter, significantly reduced its anti-oxidation directly affect the quality of pipe. The checks have a batch of the product of the project failed, the measured oxidation induction time is only 7min (200 ℃, standard ≥ 20 min), measured data is far less than the standard value, quality, a serious problem. Hydrostatic Strength does not meet standard requirements, indicating that pipe pressure capacity, and easy to burst.

In addition, a batch of random copolymer polypropylene ppr fitting failure, the main failure projects Charpy impact test. Such products in the normal transportation, handling, installation and use (especially in winter), in the event of external shocks is likely to cause rupture.