As the series of piping network products for water supply and drainage with mature technology, pipes and fittings of PVC-U are one of the largest outputs for plastic products in the world, which already had been used widely both at home and abroad. For PVC-U water supply piping network, the raw materials and finished products are both match or exceed the relative standards. So PVC-U piping network can suit for the equipments of drinking water supply. The piping networks are designed for the uninterrupted supply of water condition from 20°C to 50'C. Under this condition, service life of piping network can up to 50 years.