Spiral Steel Pipe Manufacturer

Spiral Welded Pipe: This involves rolling strips of low-carbon carbon structural steel or low-alloy structural steel into a tube blank at a specific spiral angle, known as the forming angle, and then welding the tube seam to create the pipe. It allows for the production of large-diameter steel pipes using narrower strips of steel. The specifications are indicated by the outer diameter multiplied by the wall thickness. The welded pipes must ensure that the hydrostatic test, tensile strength of the weld, and cold bending properties meet the required standards.

Execution Standards

Spiral-welded submerged arc steel pipes for pressure fluid conveyance, SY5036-83, are primarily used for pipeline transportation of oil and natural gas; high-frequency welded spiral steel pipes for pressure fluid conveyance, SY5038-83, are those焊接 using high-frequency butt welding method. These steel pipes have strong pressure-bearing capacity, good plasticity, and are easy to weld and shape. The general low-pressure fluid conveyance spiral-welded submerged arc steel pipes, SY5037-83, are made by double-sided automatic submerged arc welding or single-sided welding, and are used for conveying low-pressure fluids such as water, coal gas, air, and steam.

Common standards for spiral steel pipes typically include: SY/T5037-2000 (Ministry Standard, also known as Spiral Submerged Arc Welded Steel Pipe for Ordinary Fluid Transportation), GB/T9711.1-1997 (National Standard, also known as Technical Conditions for Delivery of Steel Pipes for Petroleum and Natural Gas Industry Transportation, Part 1: Grade A Pipes (for stricter requirements, see GB/T9711.2 Grade B Pipes)), API-5L (American Petroleum Institute, also known as Line Pipe; divided into PSL1 and PSL2 levels), and SY/T5040-92 (Spiral Submerged Arc Welded Steel Pipe for Piling).

Material

Q235A，Q235B、16Mn、20#、40#

Specs

Spiral Pipe Φ219-2320x6-22mm

Application

Spiral-welded pipes are primarily used in domestic applications such as water supply projects, petrochemical, chemical, and electrical industries, agricultural irrigation, and urban construction. They are employed for liquid conveyance, including water supply and drainage. For gas transportation, they are used for coal gas, steam, and liquefied petroleum gas. They also serve as structural components for pile driving, bridges, docks, roads, and building structures.

Production Process

Spiral-welded pipes are also a type of welding equipment, generally with higher strength than straight seam welded pipes. They can produce larger diameter pipes using narrower billets and can also produce pipes of different diameters with the same width billets. However, compared to pipes of the same length with straight seams, the weld length increases by 30~100%, and the production speed is slower. Therefore, smaller diameter pipes mostly use straight seam welding, while larger diameter pipes usually employ spiral welding.

Spiral Steel Pipe Production Process: It is a spiral seam steel pipe made from strip steel coils, formed through normal temperature extrusion, and welded using the automatic double-spiral double-sided submerged arc welding technique.

1. Raw materials, including steel coils, welding wire, and flux, must undergo rigorous physical and chemical testing before being used.

2. Steel strip ends are joined using single or double wire submerged arc welding, followed by automatic submerged arc welding for reinforcement after rolling into steel pipes.

3. Prior to forming, the steel strip is straightened, trimmed, deburred, surface cleaned, conveyed, and pre-bent.

4. The输送机sides' hydraulic cylinder pressure is controlled by an electrical contact pressure gauge, ensuring smooth steel strip transport.

5. Utilize external or internal roll forming.

6. Utilize a weld gap control device to ensure that the weld gap meets welding requirements, with strict control over pipe diameter, misalignment, and weld gap.

7. Both inner and outer welding processes utilize Lincoln welding machines for single or double wire submerged arc welding, ensuring stable welding specifications.

8. All welded seams undergo online continuous ultrasonic automatic flaw detection, ensuring 100% non-destructive testing coverage for spiral seams. In case of defects, an automatic alarm is triggered and marked, allowing production workers to adjust process parameters in real-time and promptly eliminate the defects.