We specialized in manufacturing the full size of square tubes and rectangular tubes:20X20-600X600mm,square tubes,20X30-600X800mm rectangular tubes, for more than 20 years.

Black welded pipe/square steel pipe Product Description:

Black welded pipe/square steel pipe Qualty Inspection:

Black welded pipe/square steel pipe Surface Qualty: 

1.Cold bending section steel surface can not have bubbles,cracks,inclusions and transverse stratification,wrinkle,buckle and so on. Allow slight pit,convex,indentation,scratch and presure into the iron oxide,but is not greater than 10% of nominal wall thickness.

2.Surface defects allowed use grinding method to clear up,but after cleaning the thickness should be no less than minimum allowable thickness.

3.If have special requriements on surface quality of cold bending section steel ,determined by supply and demand.

Black welded pipe/square steel pipe Welding Quality:

1.Welds of cold bending section steel shall not be skip welding,lap welding and burn through.

2.Weld flaw allowed repair welding and grinding,but  after welding and griding shold reach requirements specified in this standard.

3. Burrs around welding should be removed, burrs inside seams do not clear up,when have special request determined by supply and demand. 

Black welded pipe/square steel pipe Package&Ship:

Company Introduction :

Our company focuses on the usage, development and research of square and rectangular tubes over the passed 20 years. We purchased three production lines at the cost of over 16 million for expansion of the new factory in 2012, These production lines make full-sizes of square tubes and rectangular tubes: 20x20mm-600x600mm, 20x30mm-600x800mm, Thickness:1.0mm-35.0mm,over 2800 kinds of specifications.

Frequently Asked Questions

Q: Are you Factory or Trading Company?

 A: We are factory, our main products include square and rectangular Steel pipe.  Our products of large-diameter,thick-walled square or rectangular tubes fill the blank of domestic and abroad market.

Q: What is the Export Volume of your company?

A: We have a 200000 tons export volume per year in the past, with the expansion of the markets, the Export Volume is growing steady.

Q:Why choose our company?

A:we have passed ISO9001:2008 quality management system certification and have passed Europe Union EN10210-1:2006 CE certification in 2012.Compay resorts more variety,large  inventory,high quality,low price,short delivery time,good after-sales service and many other competitive advantages,to become designated supplier of many large enterprises,customers throughout our country in more than 20 provinces and cities and exported to the United States,Canada,Russia,India,Malaysia,Europe and other countries and regions.

Our company have passed ISO9001:2008 quality management system certification and have passed Europe Union EN10210-1:2006 ,10219-1:2006 CE certification in 2012.

Company resorts more variety,large inventory,high quality,low price,short delivery time,good after-sales service and many other competitive advantages,to become designated supplier of many large enterprises.Customers throughout our country in more than 20 provinces and cities and exported to the United States,Canada,Russia, India,Malaysia,Europe and other countries and regions.

1.customized design is available.

2.Provide free samples.

3.Reply your enquiry within 24 working hours.

4.welcom to visit our factory

5.during the using our products,our customer service staff can answer any question about the quality and technology.

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