What are the specifications of seamless steel pipe

Update time : 2023-02-15 09:03:30

　　Seamless steel pipe has hollow section and is widely used as pipeline for conveying fluid, such as pipeline for conveying oil, natural gas, gas, water and some solid materials.

　　1. First, the seamless steel pipe is expressed as the outer diameter × Wall thickness. This is because there are many wall thickness specifications of seamless steel pipes. For example, the national standard wall thickness of seamless steel pipes with an outer diameter of 300 has 23 specifications, including 7.5, 8, 8.5, 9, ------ 22.

　　2. DN is generally used to represent PVC pipe, cast iron pipe, steel plastic composite pipe and galvanized steel pipe, which means the abbreviation of English nominal diameter. The number after DN is the nominal diameter, which does not represent either the outer diameter or the inner diameter. It can be roughly understood as "average diameter", which cannot be used to calculate or compare dimensions.

　　3. The outer diameter of DN300 welded pipe is 323.9, and there are four standard wall thicknesses: 3.96, 4.57, 9.53 and 12.7.

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