Welded steel pipes are made by bending steel plates or steel strips into shape and then connecting the seams using welding. According to the welding method and usage, they can be divided into the following three types:
I. ERW (Electric Resistance Welded) Steel Pipe and Tube Mill:
Steel plates or strips are bent longitudinally into a pipe shape, and then welded along the straight edges of the pipe, with the weld seam parallel to the pipe axis. This type of steel pipe has high production efficiency and low cost, making it suitable for medium and small diameter pipes (usually DN≤710mm). Welding methods include high-frequency resistance welding (ERW) and submerged arc welding (SAW). Among them, high-frequency ERW pipes are widely used for low-pressure fluid transport, such as oil and gas pipelines, due to their fast welding speed and stable weld quality.
Our ACA group can provide high-frequency ERW pipe production lines according to customer requirements, with sizes ranging from DN12-710MM.
Our HF ERW Pipe Mill uses high-frequency resistance welding technology. The welds are stress-relieved through online annealing, with a tensile strength of over 510MPa. Dimensional tolerances meet GB/T 21835 standards, and wall thickness deviation does not exceed ±10%.
Here's the flowchart of our ERW straight seam welded pipe production line:
II. Spiral Welded Steel Pipe (SSAW Tube Mill):
Steel strips are bent into a pipe shape along a spiral direction and continuously welded, with the seam forming a spiral. This allows the production of large-diameter steel pipes (DN can exceed 3000mm) using relatively narrow steel strips. Spiral welded pipes have better stiffness and torsional resistance than straight seam pipes. They can be divided into spiral submerged arc welded (SSAW) and spiral high-frequency welded (HFW). The former has stronger pressure-bearing capacity and is commonly used in long-distance pipelines, while the latter is suitable for low-pressure situations.
Here's the general process flow for a spiral steel pipe production line:
III. Other special welded steel pipes Line, such as Stainless steel welded pipes (using TIG welding, MIG welding, etc.), which are mainly corrosion-resistant and used in industries like chemical and food processing; there are also double-sided submerged arc welded pipes, which have high-quality welds and are suitable for high-pressure conditions.
The vertical steel pipe straightening machine is a metallurgical device used to straighten metal profiles, bars, pipes, wires, and so on. The main types include pressure straightening machines, balanced roller straightening machines, and inclined roller straightening equipment. The machine features a vertical setup with bidirectional drive, equipped with two sets of staggered straightening rollers that squeeze the steel pipe. Through changes in angles, the pipe undergoes continuous elastic deformation to correct bending defects. Standard models can achieve a straightening accuracy of up to ≤0.3mm/m.
Welded steel pipes are made by bending steel plates or steel strips into shape and then connecting the seams using welding. According to the welding method and usage, they can be divided into the following three types: I. ERW (Electric Resistance Welded) Steel Pipe and Tube Mill II. Spiral Welded Steel Pipe (SSAW Tube Mill) III. Other special welded steel pipes Line
Recently, the large oil and gas pipeline bending machines was made by ACA group, After on-site inspection and approval by Kazakh technicians, the pipe bender equipment was loaded and shipped to Kazakhstan.
The challenges in large-diameter longitudinal seam welded pipe production lines mainly focus on four core areas: Steel plate forming, welding, finishing, and inspection. Below, we will mainly introduce our ACA- LSAW (Longitudinal Submerged Arc Welded) pipe production line’s forming methods and technical challenges.
High-Speed & High-end ERW pipe equipment is a professional set of machinery used to produce straight seam welded pipes through high-frequency resistance welding. Take its high-precision forming and efficient welding features, ERW/HF welded tube widely applied in industries such as oil and gas transportation, municipal pipelines, and building structures.
The inner wall of the steel pipe, after shot blasting, is coated with anti-corrosion powder using an internal spraying system through hot-melt spraying. This coating machine is specialized for internal epoxy powder anti-corrosion spraying of steel pipes, mainly used for pipeline anti-corrosion processing in the petroleum, water conservancy, and municipal fields. This internal pipe spraying anti-corrosion equipment mainly includes: mobile flat car, cantilever spray rod, internal spray gun, two-component spraying system, medium-frequency heating, dust collection and recovery system, and pipe end recovery dust removal equipment.
The Anti-Corrosion Coating processing production line is used to make two layer FBE, two layer PE, three layer PE (3PE), TPEP Two layer epoxy powder coated on external steel pipe (⌀57-1220mm).
ACA Group warmly invite you attend International Tube and Pipe Trade Fair 2026, at Dusseldorf. --Exhibition date: 13-17 APRIL, 2026 --Our booth NO.: 7-D20-2
May China and the world enjoy peace and prosperity in the new year.
Our ACA company can provide complete pipeline laying machines, PipeLine crawler pipelayer with different lifting capacities according to user requirements for pipeline construction tonnage, with maximum lifting capacities ranging from 15,000 kg to 120,000 kg.
Copyright © 2025 by ALECO Advanced Tube Machinery Co., Ltd. All Rights Reserved
Privacy Policy
