... Dress media: ethylene, propylene, oxygen, nitrogen, ammonia, liquefied petroleum gas, vinyl chloride, and natural gas, etc.; Ball piece Material: there are 16MnRWH510,WH530 ... , SPV355N, SPV490Q, IE537-2, 07MnCrMoVR, 07MnNiMoVDR, WEL-TEN610CF, JFE-HITEN610U2(L), 15MnNbR ...