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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 is the difference between welded pipe and steel pipe seamless in manufacturing?-news-TIANJIN YUANTAI DERUN PIPE MANUFACTURING GROUP CO., LTD-
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What is the difference between welded pipe and steel pipe seamless in manufacturing?
What is the difference between welded pipe and steel pipe seamless in manufacturing?

Steel pipe seamless and ERW manufacturing techniques have both been in use for many years, and each has developed over time. Which is better?

Manufacturing welded pipe

A skelp, or long, coiling ribbon of steel, is the initial form of welded pipe. When the skelp is cut to the required length, a flat, rectangular sheet is produced. The outside circumference of the pipe, which can be used to determine its eventual outside diameter, will be equal to the width of that sheet's shorter ends.

The longer sides of the rectangular sheets are rolled up toward one another to form a cylinder as they pass through a rolling machine. High-frequency electrical current is used to melt and fuse the edges together during the ERW process.

The fact that no fusion metals are used and the weld seam cannot be felt or seen is a benefit of ERW pipe. As opposed to double submerged arc welding (DSAW), which, depending on the application, leaves behind a visible weld bead that must then be removed.

The processes used to manufacture welded pipes have advanced over time. The change from low-frequency to high-frequency electric currents for welding is arguably the most significant development. Low-frequency current was used before the 1970s. Low-frequency ERW-produced weld seams were more vulnerable to corrosion and seam failure.

The majority of welded pipe types need to be heat treated after production.

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Manufacturing steel pipe seamless

A billet of steel is the basic building block of steel pipe seamless. Billets are pierced through the center with a mandrel while they are still hot. Rolling and stretching the hollow billet comes next. The billet is carefully stretched and rolled until steel pipe seamless reaches the length, diameter, and wall thickness that the customer order specifies.

Some steel pipe seamless types don't need heat treatment because they harden during manufacturing. Others do need to be heated. If heat treatment is necessary, check the specification of the steel pipe seamless type you're considering.