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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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What should be paid attention to when welding galvanized pipes?-news-TIANJIN YUANTAI DERUN PIPE MANUFACTURING GROUP CO., LTD-
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What should be paid attention to when welding galvanized pipes?
What should be paid attention to when welding galvanized pipes?

Welding of galvanized pipe should pay attention to:

1. Galvanized steel pipes with a pipe diameter greater than 100mm should be connected by flanges or ferrule-type special pipe fittings.

2. For the weld between galvanized steel pipe and flange, in order to ensure the welding quality, the weld joint should be galvanized, and the galvanized layer should be cleaned by hand grinding wheel or sandpaper, or the galvanized layer should be removed by gas welding flame.

3. The weld between the galvanized steel pipe and the flange should be galvanized twice.


galvanized pipes.jpg


Measures to ensure welding quality include:

1. The human factor is the control focus of gas galvanized pipes welding. Due to the lack of necessary post-welding control means, it is very easy to cut corners and affect the quality; at the same time, the special welding of galvanized pipes makes it difficult to guarantee the welding quality. Therefore, before the start of the project, welders who are skilled in technology and hold corresponding boiler and pressure vessel certificates or equivalent welder certificates should be selected for necessary technical training and disclosure. Permission to enter the site for welding. It is not allowed to be replaced at will to ensure that the welders who weld the pipeline are relatively stable.

2. Control of welding consumables: ensure that the purchased welding consumables are from formal channels, have quality assurance certificates, certificates of conformity, and meet the process requirements; the acceptance of welding consumables, the procedures for receiving and issuing materials must be formal and complete, and the recycling of welding rod heads should be strictly controlled to ensure the flow direction , Dosage; Welding consumables should be baked strictly according to the process, and no more than half a day's dosage should be distributed at a time.

3. Welding machine; Welding machine is a welding tool, which must ensure reliable performance and meet the process requirements; the welding machine must have a current and voltmeter that has passed the verification to ensure the correct implementation of the welding process. The welding cable should not be too long, and the welding parameters should be adjusted if it is longer.

4. Welding process method: ensure the strict implementation of special operation methods for galvanized pipes, check the groove before welding according to the welding process, control the welding process parameters and operating methods, check the appearance quality after welding, and add non-destructive testing after welding if necessary. Control the welding level and the amount of welding consumables for each pass.

5. Welding environment control: ensure that the temperature, humidity and wind speed during welding meet the process requirements. Welding is not allowed under unconditional conditions.