304 flange is a kind of stainless steel flange, that is, 0Cr18Ni9, which has better comprehensive performance, so the market consumption is relatively large, and carbon steel flange also has a relatively high market share, but they cannot replace each other. 304 has durability Corrosion and non-rusting characteristics, and carbon steel flanges are prone to rust when they encounter water or humid air, thereby reducing the service life, so carbon steel cannot be used where stainless steel is required, such as many chemical plants, pharmaceuticals and other fields Stainless steel, transport some sand and gravel, etc. Where carbon steel can be used, sometimes it depends on the cost budget, and the price difference between the two is relatively large. Material Carbon steel ASTM…