Seamless steel pipe is widely used, the application of such a wide range of seamless steel pipe, how to achieve the quality of seamless steel pipe guarantee? How to identify the quality? What is the implementation standard? Next let's learn about it together.
Seamless steel pipe implementation standards
1, structural seamless steel pipe: GB/T8162-2008
2, conveying fluids with seamless steel pipe: GB/T8163-2008
3, low and medium pressure boiler tube boiler seamless steel pipe: GB/T3087-2008
4、High pressure seamless steel pipe for boiler: GB/T5310-2008(ST45,8-Ⅲ)
5、High pressure seamless steel pipe for chemical fertiliser 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 pipe for oil cracking：GB/T9948-2006
9、Seamless steel pipe for oil drilling collar: YB691-70
10、Seamless Steel Pipe for Automobile Semi-axle：GB/T3088-1999
11, Seamless steel pipe for ships: GB/T5312-1999
12, Cold-drawn and cold-rolled precision seamless steel pipe: GB/T3639-1999
13、All kinds of alloy pipe 16Mn, 27SiMn, 15CrMo, 35CrMo, 12CrMov, 20G, 40Cr, 12Cr1MoV, 15CrMo.
In addition, there are GB/T17396-2007 (hot-rolled seamless steel pipe for hydraulic strut), GB3093-1986 (high-pressure seamless steel pipe for diesel engine), GB/T3639-1983 (cold-drawn or cold-rolled precision seamless steel pipe), GB/T3094-1986 (cold-drawn seamless steel pipe shaped steel pipe), GB/T8713-1988 (hydraulic and pneumatic cylinder), GB/T3639-1983 (cold-drawn or cold-rolled precision seamless steel pipe), GB/T3094-1986 (cold-drawn seamless steel pipe shaped steel tube), GB/T8713-1988 (hydraulic and pneumatic cylinder) GB/T8713-1988 (hydraulic and pneumatic cylinder with precision inner diameter seamless steel pipe), GB13296-2007 (boiler, heat exchanger with stainless steel seamless steel pipe), GB/T14975-1994 (structural stainless steel seamless steel pipe), GB/T14976-1994 (stainless steel seamless steel pipe for fluid transmission) GB/T5035-1993 (automotive semi-axle casing with seamless steel pipe), API SPEC5CT-1999 (casing and tubing specification) and so on.
How to identify the quality of seamless steel pipe?
1, shoddy steel pipe is prone to folding.
Folding is a variety of folding lines formed on the surface of the steel pipe, this defect is often throughout the longitudinal direction of the product. The reason for the folding is due to the shoddy manufacturers to pursue high efficiency, the amount of underpressure is large, resulting in the ear, the next rolled on the folding, folded products will crack after bending, the strength of the steel is greatly reduced.
2, the appearance of shoddy steel pipe often has the phenomenon of numbness.
Pockmarking is due to the rolling groove wear caused by serious irregularities in the surface of the steel uneven defects. Because of the shoddy steel pipe manufacturers to pursue profits, often rolling groove rolling exceeds the standard.
3, the surface of the shoddy steel pipe is prone to scarring.
There are two reasons: (1), shoddy steel pipe material is not uniform, more impurities. (2), shoddy material manufacturers guide equipment is simple, easy to stick to the steel, these impurities bite the rollers are prone to scarring.
(4), shoddy material surface is easy to produce cracks, the reason is that its billet is adobe, adobe porosity, adobe in the cooling process due to thermal stress.
In the process of cooling due to the role of thermal stress, cracks, after rolling there are cracks.
5, shoddy steel pipe is easy to scratch, the reason is shoddy steel pipe manufacturers poor equipment, easy to produce burrs, scratching the surface of the steel. Deep scratching reduces the strength of steel.
6, shoddy steel pipe without metal luster, reddish or similar to the colour of pig iron, there are two reasons two, its billet is adobe. 2, shoddy material rolling temperature is not standard, their steel temperature is measured visually, which can not be rolled according to the specified austenite region, the performance of the steel naturally fails to meet the standards.
7, shoddy steel pipe crossbar thin and low, often filled with the phenomenon of dissatisfaction, the reason is that manufacturers in order to achieve a large negative tolerance, the finished product of the first few passes of the undercutting amount of bias, the iron type is small, the hole is not filled with.
8, shoddy steel pipe cross-section is oval, the reason is that manufacturers in order to save materials, finished rolls before the second pass under the amount of large, the strength of this rebar greatly reduced, but also does not meet the standards of the external dimensions of the rebar.
9, the composition of the steel is uniform, the tonnage of the cold shear is high, the cut end surface is smooth and neat, while the shoddy material due to the poor material, the cut end surface will often have the phenomenon of meat loss, that is, uneven, and no metallic luster. And because of the shoddy material manufacturers products cut head less, head and tail will appear big ears.
10, shoddy steel pipe material contains more impurities, the density of steel is small.
11, shoddy steel pipe inner diameter size fluctuation is large, the reason is; l, steel temperature is not stable with yin and yang surface. 2, the composition of the steel is not uniform. 3, due to the poor equipment, low foundation strength, the mill's bounce. Will appear to have the same week with a large change, so that the steel force is not uniform easy to produce fracture.
12, the tube's trademark and printing are more standard.
13, three steel pipe diameter 16 or more large threads, the spacing between the two trademarks are above IM.
14, shoddy steel rebar longitudinal bars are often wavy.
15, The shoddy steel pipe manufacturers are loosely packed because they do not have a travelling car. The sides are oval shaped.
The above is what I have shared for you, I hope it will help you. If you have more knowledge about seamless steel pipe need to know, please contact us in time.