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Executive standards and quality appraisal methods for seamless steel pipes in China

Seamless steel pipes are widely used, how can the quality of seamless steel pipes be guaranteed? How to distinguish quality? What are the execution standards? Let's take a look together next.

Executive standard for seamless steel pipes.


1. Seamless steel pipes for structural purposes: GB/T8162-2008
2. Ground seam steel pipes for fluid transportation: GB/T8163-2008
3. Seamless steel pipes for low and medium pressure boiler tubes: GB/T3087-2008
4. High pressure seamless pipes for boilers: GB/T5310-2008 (ST45, 8-III type)
5. High pressure seamless steel pipes for fertilizer equipment: GB/T6479-2000
6. Seamless steel pipe for geological drilling: YB235-70
7. Seamless steel pipe for oil drilling: YB528-65
8. Seamless steel pipes for petroleum cracking: GB/T9948-2006
9. Seamless pipe for petroleum drill collars: YB691-70
10. Seamless steel pipes for automotive axle shafts: GB/T3088-1999
11. Seamless steel pipes for ships: GB/T5312-1999
12. Cold drawn and cold-rolled precision seamless steel pipes: GB/T3639-1999
13. Various alloy pipes 16Mn, 27SiMn, 15CrMo, 35CrMo, 12CrMov, 20G, 40Cr, 12Cr1MoV, 15CrMo
In addition, there are GB/T17396-2007 (Hot rolled seamless steel pipes for hydraulic props), GB3093-1986 (High pressure seamless steel pipes for diesel engines), GB/T3639-1983 (Cold drawn or cold rolled precision seamless steel pipes), GB/T3094-1986 (Cold drawn seamless steel pipes with irregular shapes), GB/T8713-1988 (Precision inner diameter seamless steel pipes for hydraulic and pneumatic cylinders), GB13296-2007 (Stainless steel seamless steel pipes for boilers and heat exchangers), GB/T14975-1994 (Stainless steel seamless steel pipes for structural purposes) GB/T14976-1994 (Stainless Steel Seamless Steel Tubes for Fluid Transportation) GB/T5035-1993 (Seamless Steel Tubes for Automotive Halfshaft Sleeves), API SPEC5CT-1999 (Specification for Sleeves and Tubing), etc.
How to identify the quality of seamless steel pipes?
1. Fake and inferior steel pipes are prone to folding.
Folding is a variety of creases formed on the surface of steel pipes, which often run through the longitudinal direction of the entire product. The reason for folding is due to the pursuit of high efficiency by fake and inferior manufacturers, which results in excessive reduction and the generation of ears. Folding occurs during the next rolling process, and the folded product will crack after bending, resulting in a significant decrease in the strength of the steel.
2. The appearance of fake and inferior steel pipes often shows pitting.
Pitted surface is a defect caused by severe wear and tear on the rolling groove, resulting in irregular unevenness on the steel surface. Due to the pursuit of profit by fake and inferior steel pipe manufacturers, there are often cases where rolling grooves exceeds the standard.
3. The surface of fake and inferior steel pipes is prone to scabbing.
There are two reasons: (1) The material of fake and inferior steel pipes is uneven and there are many impurities. (2) Fake and inferior materials

Post time: Aug-18-2023