Quality parameters at the metal bellows type assembly does not involve the use of such parameters, only if the elastic element performance testing and quality assessment for direct measurement of these parameters. According to the test results to determine the functional elements, quality, and reliability of the failure. Metal bellows. Physical performance HDPE Pipe: Item Index Test Method ring stiffness KN / ㎡SN4≥4GB / T9647SN8≥8 ring when the flexible deformation of the shape of the 30% does not crack GB / T9647 Longitudinal reversion rate ≤3% GB / T6671. 2 hammer impact pipe wall is not broken, do not disengage the two walls GB / T14152 joints sealing test no leakage GB / T6111 seam tensile strength reaches a predetermined value GB / T19272.2 two-out plastic (Figure), metal bellows bellows provided by Xiong Zan Pair bright plastic products factory. Xiong Zan Pair Ming plastics factory (1620231.707070.cn) located Xiongxian meters north industrial area. Scraps and development in the wave of market economy, the current two-out plastic has a high profile in UPVC pipe, enjoys a good reputation. Double clear plastic made whole network business alliance certification, marking our service and management level has reached a new height. Two-out plastic all employees willing to work with all people of insight and common development, for a better future.