Straight Seam Welded Steel Pipe

With stable mechanical properties, precise specification tolerances, and high adaptability for processing, the Straight Seam Welded Steel Pipe supplied by Shixinda manufacturer is widely applicable to various scenarios such as civil building accessories, industrial equipment pipelines, garden protective facilities, mechanical and electrical installation, and lightweight steel structure construction. The standardized mass production process ensures stable and controllable pipe quality, high consistency in batch supply, and can meet both small-scale scattered purchases and large-scale engineering batch matching requirements. It is a universal industrial pipe that combines quality, practicality, and economy.

Basic Definition

Straight seam welded pipe is the full name of straight seam resistance welded pipe (ERW), which refers to a steel plate / steel strip rolled into a cylindrical shape, with the weld seam parallel to the axis of the pipe, and through high-frequency resistance heating and extrusion forming to produce a welded pipe.

Production Process: Steel strip unwinding → leveling → forming → high-frequency resistance welding → weld seam deburring → sizing and straightening → cutting to length → flaw detection;

Classification: Classified by forming as roller-type cold-bent straight seam welded pipe; classified by wall thickness as thin-walled and thick-walled; classified by surface as black pipe, hot-dip galvanized / zinc-aluminum-magnesium straight seam welded pipe;

Commonly used standards: GB/T 3091 (general for water supply and drainage, steel structure), GB/T 13793 (ordinary straight seam electric welded pipe), API 5L (oil and gas transportation industrial grade);

Appearance Characteristics: The pipe body has only one parallel longitudinal weld seam, different from the spiral weld seam of spiral welded pipes.

Core selling point

1. High dimensional accuracy, stable tolerance

The steel strip is cold-rolled for shaping, with extremely small errors in outer diameter, wall thickness, and length. The roundness and straightness are superior to spiral welded pipes; no secondary correction is needed for processing holes, flanges, and threading, and it is suitable for precision steel structures and equipment supports.

2. Reliable weld quality, strong pressure-bearing performance

High-frequency resistance welding without filler wire, the weld seam is integrated with the base material, with few internal defects; it can be subjected to water pressure, eddy current, and ultrasonic testing, and has stable pressure-bearing performance, suitable for water supply and drainage, low-pressure fluid, photovoltaic supports, and pipeline transportation.

3. Smooth inner and outer surfaces, friendly for anti-corrosion processing

Welding spurs can be ground flat online, the pipe wall is flat without bumps or depressions, galvanizing, painting, and plastic coating have strong adhesion, and are not prone to peeling or rusting; thin-walled straight seam pipes have low fluid resistance and lower water and gas loss during transportation.

4. High cost-performance ratio, short delivery cycle

The raw material for Straight Seam Welded Steel Pipe is flat steel strip, with high production efficiency, and the unit price is lower compared to seamless pipes and spiral welded pipes of the same specification; regular specifications are in ample supply, and can be cut to the required length as needed, reducing waste.

5. Wide range of specifications, suitable for multiple scenarios

Small diameters (DN15) to medium-large diameters (DN600) can be produced, thin-walled is used for guardrails, photovoltaic supports, and wiring pipes; thick-walled is used for factory steel structures, low-pressure fluid pipelines, and engineering vehicle frames.

6. Lightweight and easy to construct

With thinner wall thickness under the same load-bearing capacity, the pipe material has less weight, reducing time and effort for transportation, hoisting, welding, and installation; the pipe ends can be directly bevel-cut, thread-cut, or expand-cut, and on-site processing is simple.

Advantages

1. The water pressure testing standard is strict, and the sealing and pressure-bearing are more reliable.

Complying with the national standard water pressure test specifications, ERW welded pipes have a pressure retention of 2.5–5 MPa for 5 seconds, while LSAW large-diameter pipeline pipes are tested under high pressure according to API standards for 10 seconds per pipe to prevent leakage and bulging defects; combined with eddy current/ultrasonic weld seam flaw detection for dual inspection, the weld seam is dense and the fluid transportation is long-term leak-free, suitable for various pressure-bearing conditions such as water supply and drainage, gas, and oil transportation.

2. The pipe material size accuracy is high, and the overall pressure-bearing is uniform and stable.

The steel strip is continuously rolled and the steel plate is precisely formed by JCOE, with strict control of outer diameter and wall thickness tolerances, and the pipe body ellipticity and misalignment are well controlled; throughout the water pressure test process, there are no local stress weak points, the entire pipe is evenly stressed, and it is less likely to deform or crack under medium and low pressure and large-diameter heavy-load pressure-bearing conditions, and the installation and connection sealing performance is better.

3. The entire process quality control system is complete, with a long service life and low operation and maintenance costs.

From raw material selection, forming and welding, weld bead grinding to water pressure testing and non-destructive testing, the entire process is self-inspected, and hidden defects such as layering, cracks, and false welding are screened out before leaving the factory; the base quality of the pipe material is stable, and after galvanizing and 3PE anti-corrosion processing, the adhesion is strong. For underground and outdoor projects, it is resistant to corrosion and leakage, significantly reducing the later maintenance and replacement costs.

4. A complete range of specifications, with high cost-effectiveness suitable for various projects.

It can produce small-diameter ERW straight seam welded pipes and large-diameter thick-walled LSAW submerged arc welded pipes, with materials covering Q235B, Q345B, and pipeline steel X42/X70, etc.; under the same pressure-bearing standard, the price is better than seamless steel pipes, and it is ensured by high-standard water pressure testing for safety use, and it also meets the needs of various projects such as scaffolding, municipal pipelines, oil and gas long-distance transportation, and pile foundation steel structure.

Common structural straight seam welded pipe specifications available on the market (GB/T13793)

Straight Seam Welded Steel Pipe is a steel pipe formed by rolling a steel strip and welding it with high-frequency resistance welding, with the weld seam parallel to the axis of the pipe. It complies with standards such as GB/T3091 and GB/T13793, and is suitable for various fields including fluid transportation, steel structures, and photovoltaic supports.

Shixinda mainly focuses on the production of a full range of straight seam welded pipes. Relying on the local industrial supply chain, it has created multiple core advantages. The pipe dimensions have strict precision, with minimal wall thickness and roundness errors, smooth inner and outer surfaces of the pipe wall, online milling of the weld seam, stronger adhesion of galvanization and painting, lower fluid transportation resistance. It uses hot-melt welding without welding wire, with the weld seam formed as a whole, and each batch undergoes water pressure and eddy current testing for pressure stability and durability. 

Compared with seamless and spiral welded pipes, Shixinda's straight seam welded pipes have higher production efficiency and higher yield rate, with outstanding cost performance. Regular specifications are in ample supply, and it supports on-demand cutting by length, reducing material waste for customers. The pipes cover thin-walled guardrails and thick-walled engineering pipes, and can be processed for hot galvanization, zinc-aluminum-magnesium anti-corrosion, and are suitable for scenarios such as factory frames, municipal water supply and drainage, photovoltaic supports, and engineering vehicle frames.

Shixinda strictly controls raw materials and factory quality inspections, has a complete range of specifications, and quick delivery. It provides one-stop cutting, beveling, and threading processing services. With stable quality and considerate supply, it offers high-performance straight seam welded pipe overall purchasing solutions for domestic and international engineering customers.