... service 3 Reasonable price 4 Various styles Detailed product description Carbon Steel Pipes 1. Standard:GB5310-2008, GB6479-2000, ASTM, ... -111, DIN 17175, GB8163-2008, GB9948-2006, GB8162-20082. Carbon Material:20#, 35#,45#,CK45,ST45,ST55,SA106B3. Alloy Material ... rise and fall accompany with the marketthe material and the grade .Diffrent materials sometimes mean hundreds dollars .the sizes.generally ...