... FLANGE 1-standards:ASTM,BN API,etc 2-material:carbon steel, alloy steel,etc 3-a large stock -a big manufacturer of ... , LF2, F304, F304L, F316, F316L and Q235 steelabout us Zhonghao steel pipe sales Co.,Ltd. of Cangzhou is a pipeline, pipe ... North China.The main products include: seamless steel pipe, straight seam steel pipe, spiral steel pipe, welded steel pipe, elbow, tri -elbow, different-diameter ...