閥座環(huán)–硬面閥座環(huán)焊入閥體內(nèi).Seat Ring – hard faced seat rings are welded to body.整體后座–硬面,使用壽命最長(zhǎng).Integral Backseat – hard faced for maximum backseat life.帶有H的閥內(nèi)件型號(hào)具有鈷合金硬面閥座環(huán)表面.Trim numbers with H have cobalt alloy hard faced seat ring...