These parts are made for CRCC group used for railway damping air spring.Their materials are ZG230-450,ZG270-500,ZG310-570 according to GB699-2015.And we can also make other materials according to different standars like AAR and ASTM standard,JIS,EN,IS2062(India Standard) and so on.And we also have different casting process like Sand casting,Coated sand casting,Silica sol casting.We have complete testing equipment to ensure our productions are high quality and meet your need,like Magnetic particle flaw detector,X-ray flaw detector and so on.