... of API and became a member of first – grade supply network of State Power Corporation and China National Petroleum Corporation ... DIN2637 Types: Welding neck FflangesSlip on FlangesThreaded FlangesSocket Welding Flanges, Blind FlangesPRESSURE GRADE: 6Bar,10Bar,16Bar,25Bar,40Bar SIZE: DN10- ... on Flanges, Screwed Boss Flanges, Slip on Boss Flanges, Blind Flanges TYPES: Table: D, E, F, H SIZE: 1/2" NB TO ...