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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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The reason for phosphating of square tube-news-TIANJIN YUANTAI DERUN PIPE MANUFACTURING GROUP CO., LTD-
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The reason for phosphating of square tube
The reason for phosphating of square tube

1. Interval time

If the interval between each production process is too long, it will cause secondary rusting of the q345b square pipe during the entire operation process. Especially when there is a pickling process, the pipes after phosphating treatment are easy to oxidize, rust, and turn green in the air. Providing water conservation maintenance during the production process can reduce rust.

High-speed rail steel tube.jpg

2. Heating tube of pickling equipment

Although the selection of raw materials for pickling equipment heating tubes is not part of the production process, if no reminder is given, it may cause the industrial equipment design staff to be careless. Fiberglass, marble, and plastic are the only raw materials for pickling equipment for sulfuric acid and hydrochloric acid phosphating treatment. The heating tubes can only use lead-antimony alloy tubes and ceramic tubes, but stainless steel plates cannot be used.

3. Making process holes

For square pipes prone to blind spots and water accumulation, try to choose appropriate locations to drill production holes to ensure that the water can flow out adequately in a short period. Otherwise, it will cause stringing or long-term draining in the air, causing secondary rust and affecting the expected effect of phosphating treatment.