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Tianjin Yuantai Derun Pipe Manufacturing Group Co., Ltd., established in March 2002, is the biggest manufacturer specializing in  ERW square&rectangular tube/pipe, hollow section structure pipe, galvanized pipe and spiral welding pipe in China. Annual output reaches 5 million tons.Yuantai Derun has 59 production lines of black ERW pipe, 10 production lines of galvanized pipe and 3 production lines of spiral welding pipe. Square pipe from 20*20*1mm to 500*500*40mm, rectangular pipe from 20*30*1.2mm to 400*600*40mm,  welded pipe from 2”—60” can be manufactured. Yuantai Derun can manufacture square rectangular pipes as per the standards of ASTM A500, JIS G3466, EN10219, DIN2240, BS1387, AS1163.

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January 1993

Key team members of Yuantai Derun group began technical job in Tianjin Daqiuzhuang tube factory.

June 2002

Tianjin Yuantai Industry & Trade Co., Ltd. was founded, specialize in square, rectangular hollow steel pipe, hot galvanized welded (hot dip galvanized) square tube, the registered capital is USD 10 million.

May 2004

One of Yuantai subsidiaries Tangshan Lituo Steel Tube Co., Ltd. was established, specialize in square rectangular straight welded hollow steel pipe, registered capital is USD 10 million.

April 2005

Yuantai Steel Square Pipe Co. Ltd. was established, specialize in square welding hollow steel tube and galvanized tube, the registered is USD 2 million.

March 2010

Tianjin Yuantai Runxiang commercial trade company was established, specialize in strip steel trade, galvanized pipe agent, etc., the registered capital is USD 2 million.

March 2010

Tianjin Yuantai Derun pipe manufacturing group Co. Ltd. was formally established, marking that the production of high-frequency welded black, galvanized square pipe, spiral welded pipe, pipe logistics and pipe trade as one of the large-scale joint enterprise Yuantai Derun group was formally established, the group registered capital is USD 20 million.

March 2010

Tianjin Yuantai Derun Investment Co., Ltd. was formally established, specialize in steel pipe industry chain,lower industry mergers and acquisitions and industrial real estate development, the registered capital is USD 2 million.

August 2013

Tianjin Derun Runfeng pipe manufacturing Co. Ltd was established, specialize in hot galvanized (hot galvanizing) processing business, the registered capital is USD 8 million.

March 2015

Tianjin Yuantai Yuanda anti-corrosion insulation pipe Co., Ltd. was established, specialize in spiral welded pipe production and sales, the registered capital is USD 2 million.

August 2015

Tangshan Yuantai Derun Pipe Co., Ltd. was established, specialize in steel strip, steel pipe trade, registered capital is USD 1 million.

March 2016

Tianjin Yuantai Derun International Trade Co., Ltd was established,mainly engaged in international import and export business for Yuantai Group, registered capital is USD 2 million.

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GB/ T 6728-2002 Cold formed steel hollow sections for general structure-news-TIANJIN YUANTAI DERUN PIPE MANUFACTURING GROUP CO., LTD-
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GB/ T 6728-2002 Cold formed steel hollow sections for general structure
GB/ T 6728-2002 Cold formed steel hollow sections for general structure

GB/ T 6728-2002 Cold formed steel hollow sections for general structure

 

The standard is applicable to round, rectangular and square cold forming hollow sectional steel made of cold-rolled or hot-rolled steel plates, sheets and strips on continuous roll cold forming units. It is also applicable to continuous hot-dip plated sectional steel. However, it is not applicable to sectional steel made by drawing, stamping, bending, etc., and sectional steel made of galvanized steel plates, sheets and strips which are cold-formed and welded.

 

The standard corresponds to EN10219-2—1997 and ISO 4019:1982. Cold-formed steel is widely used in the production of structural parts and auxiliary parts, such as construction, railway vehicles, automobiles and ships.

 

Tolerance of Wall Thickness :

Not more than ±10% of the specified wall thickness when the wall thickness is 10mm, and not more than ±8% of the specified wall thickness when the wall thickness is  10mm.

 

Tolerance of Twist:

Twist tolerance of cold-formed steel hollow sections must not more than ±1.5%.

 

Tolerance of Length:

Grade

Length(mm)

Tolerance(mm)

Ordinary level

4000-12000

+70

0

 

Precision level

4000-6000

+5

0

>6000-12000

+10

0

Tolerance of R-corner:

 

Wall Thickness(t/mm)

R-corner

Carbon steelσs320MPA

Low-alloy steelσs>320MPA

t3

1.0-2.5t

1.5-2.5t

3<t6

1.5-2.5t

2.0-3.0t

6<t10

2.0-3.0t

2.0-3.5t

t>10

2.0-3.5t

2.5-4.0t