... the installment error , could not absorb displacement ,maindly used on valve , pump3)Material :Q235,QT400-15,QT450-10.C. ... approved by ISO 9001:2008 ISO14001:2004, products are used on keyp projects , and self decided export to South Korea,USA,SPAIN ... used as the pipe line for city governments petrify,chemical industry,metallurgy,petroleum,chemistry,ships,light industries,environment protection ...