20MM~508MM Outer Diameter Q235 Black 20# 45# 16mn Large Diameter Spiral Welded Steel Pipe

• Quality control, dimension standard. The raw materials have undergone strict physical and chemical tests.
• Non-standard outer diameter, non-standard length, non-standard thickness of spiral welded pipe products, to meet customer's various personalized needs.

Inspection process
Raw material inspection -- leveling inspection -- butt welding inspection -- molding inspection -- internal welding inspection -- external welding inspection -- pipe cutting inspection -- ultrasonic inspection -- groove inspection -- external dimension inspection -- X-ray inspection -- hydraulic test -- final inspection

In order to ensure the quality of products, we have developed a complete quality plan, on-site work procedures and inspection, test plans.

Spiral welded pipe and straight seam welded pipe technical characteristics do a simple comparison:

Metallurgical properties of materials

Straight seam submerged arc welded pipe is made of steel plate, while spiral welded pipe is made of hot rolled coil. Hot strip mill rolling process has a series of advantages, it has the metallurgical process ability to produce high quality pipeline steel. For example, a water cooling system installed on the output bench to speed cooling allows the use of low alloy composition to achieve special strength grades and low temperature toughness, thus improving the weldability of the steel. But this system is largely absent in steel mills. The alloy content (carbon equivalent) of coil plates is often lower than that of similar grade steel plates, which also improves the weldability of spiral welded tubes.

More importantly, because the rolling direction of spiral welded pipe is not perpendicular to the axis of steel pipe (its clamping depends on the spiral Angle of steel pipe), and the rolling direction of straight seam steel pipe is perpendicular to the axis of steel pipe, the anti-cracking performance of spiral welded pipe material is better than that of straight seam steel pipe.

Welding process

From the welding process, the spiral welded pipe and straight seam steel pipe welding method is consistent, but the straight seam welded pipe will inevitably have a lot of t-shaped weld, so the probability of weld defects is also greatly improved, and the t-shaped seam welding residual stress is larger, the stress state of the weld metal are often in a three-way increases the possibility of a crack.

Moreover, according to the technological provisions of submerged arc welding, every weld should have arc initiation and arc extinguishing, but each straight seam welded pipe cannot meet this condition when welding around the seam, so there may be more welding defects at the arc extinguishing.

Jiangsu Irunt Steel Group Co., Ltd. is located in Wuxi City , Jiangsu Province, China, which is the largest steel production base. After 30 years of efforts, it has grown from a family factory to a group company.

The group company mainly produces and sells a series of steel products such as steel pipe, steel coil, steel plate, copper pipe, copper plate, copper strip, aluminum pipe, aluminum plate, galvanized steel pipe, galvanized coil, galvanized plate and so on.The group company has established five platforms, including three production plants and two processing plants. At present, it is still expanding its production line, basically forming a development model of integration of production, processing and sales.

Our annual production capacity of various specifications is about 1 million metric tons. In addition to being a supplier of our series of products, the group company is also committed to expanding its commitment to customers by strengthening services and adding new facilities. A dedicated team is responsible for providing technical support, recommending the correct use of steel, and assisting customers to give full play to their products.

Over the years, we have opened up new markets in Africa, Southeast Asia, the Middle East and America. Our best service and excellent quality have led long-term partners in many countries and established continuous business relations with all customers. Our principle is "service first, sales second". Most of the time, we have comprehensive inspection and procurement to control the quality of finished products. We will have a professional inspection team to test each delivery of products.

Since its establishment, in line with the mission of "contributing high-quality products and services to the world" and the core values of "customer first, excellence, coexistence and win-win", we ensure that we can deeply cooperate with all our friends in the field of iron and steel, and win more affirmation and praise from the market and customers with its high-quality products, perfect product team and thoughtful service, I believe tomorrow will be better!