The HG series high frequency welded pipe unit adopts the roller forming principle to continuously produce straight seam welded pipes. It adopts high frequency induction welding and can produce not only round pipes, but also square and rectangular pipes and special-shaped pipes that do not exceed the processing range of round pipes.

ERW Tube Mill Machine

An ERW tube mill machine is a type of industrial equipment used for manufacturing electric resistance welded steel pipes and tubes. The machine forms steel strip into a tubular shape and welds the seam using high-frequency induction technology. Great Wall’s ERW tube mill machines are engineered for precision, durability, and high-speed automatic operation, serving a wide range of industries such as construction, furniture, automotive, and fluid transport.

Tube Mill Machine Comparison

The FFX Technology Tube Mill Line incorporates the internationally advanced FFX forming process, which offers a range of advantages including stable forming, excellent surface quality of steel tubes, and easy to change specifications. This forming machine is divided into two sections: rough forming and fine forming. The rolls in the rough forming section can accommodate various specifications of steel tubes, reducing the number of rolls required by 30% to 60% compared to conventional roll forming units. This not only saves on roll inventory but also minimizes roll changeover and adjustment time, significantly enhancing production efficiency. Additionally, the use of segmented rolls instead of integral rolls reduces the need for spare parts storage.

Working Principle of Pipe Making Machine

The FFX (Flexible Forming and expanding) pipe making machine is an advanced tube forming system that utilizes a single set of universal forming rolls to produce different pipe sizes without roll changing. It significantly improves production efficiency, reduces downtime, and enhances dimensional accuracy.

Process Overview:

1. Uncoiling & Shearing
   Steel coils are uncoiled and cut into strips with the required width.

2. Strip Entry & Welding Preparation
   The strip passes through a shear and end welder, then enters the accumulator or loop bridge for continuous feeding.

3. Flexible Forming (FFX System)

• The strip is gradually formed into a round tube by universal shared rolls, not fixed per size.

• Roll stands automatically adjust position via servo motors or hydraulic controls to match the desired pipe diameter.

4. High-Frequency Welding (ERW)
   The edges of the formed tube are heated by high-frequency induction and pressed together to form a solid longitudinal weld seam.

5. Weld Seam Scarfing & Cooling
   Internal and external weld beads are removed. The tube is then air or water cooled.

6. Sizing and Straightening
   The tube enters a series of sizing stands to achieve final outer diameter and roundness. Straightening follows.

7. Cutting to Length
   A flying saw or cold saw cuts the pipe to the required length without stopping the line.

8. Output & Stacking
   Finished pipes are conveyed to a run-out table and bundled for packaging.

Key Features of FFX Technology:

Cold bending profile steel and square/rectangular pipe line is the equipment used for production of open-mouthed and close-mouthed profile steel. With combined type of rollers, and multi points pre-bending forming technology, rollers can be changed quickly with no necessary to remove main axis or stands. Further, with the low loading, it can reduce 80% of rollers cost and 90% of time for changing rollers. All specified open or close mouthed profile steel can be produced with one set of combined rollers. lt is suitable for multi-specification small batch production and meet the market requirement as well.

Square Tube Mill Line Supplier

Square tube mill line is an industrial production line used to manufacture square or rectangular steel pipes directly from steel strips through continuous roll forming, high-frequency welding, sizing, and straightening processes. Compared to traditional round-to-square forming, direct square forming improves precision and material utilization. As a professional square tube mill line supplier, Great Wall offers a complete range of high-performance tube mill equipment for square and rectangular tubes.

Working Principle of Square Tube Mill Line

The process begins with steel coil uncoiling, followed by leveling and shearing. The strip is then fed into the forming section where rolls progressively shape it into square or rectangular forms. High-frequency induction welding bonds the edges, after which the welded tube undergoes sizing, straightening, cutting, and stacking. Great Wall’s square tube mill lines feature solid-state HF welding, CNC control systems, and automatic adjustment modules to ensure stability and consistency across production runs.

Application Scenarios for Square Tube Mill Lines

Square and rectangular steel tubes produced by Great Wall square tube mill lines are widely used in:

• Steel structure construction (e.g., warehouses, stadiums)

• Guardrails and fencing

• Mechanical structures and frames

• Automotive chassis and components

• Solar mounting structures

• Agricultural machinery

Why Great Wall Is Your Trusted Square Tube Mill Line Supplier

• In-house CNC machining, roll forming, and assembly lines

• ISO 9001 certified, CE-compliant manufacturing process

• Pre-shipment full trial assembly & performance testing

• Turnkey service: layout design, training, and after-sales support

• Fast spare parts supply & global technical assistance

• 1,000+ projects delivered across 25+ countries

Great Wall ensures stable performance, fast delivery, and full engineering support for every square tube mill line.

Large-diameter thin-walled welded pipes are important pipes for transportation and structure in industrial production. They are suitable for long-distance pipelines and large steel structure projects in industries such as petroleum, natural gas, and chemicals.

This production line is mainly customized according to customer needs. The welded pipes produced have large diameters, thin walls, and good appearance. They can withstand high pressure and reduce weight and installation costs

Production process:

Process: loading → unwinding → straightening → clamping and leveling → shearing and welding →Accumulator→ forming, high-frequency extrusion welding, removing external (internal) burrs, weld polishing, weld flaw detection, water cooling, sizing, rough straightening → Saw cutting → conveyor rollers → automatic packaging → marking → inspection and collection → storage

Small-diameter thick-walled welded pipes are widely used in water and gas pipelines in the construction and manufacturing industries, as well as in power, shipbuilding, automobile manufacturing, and machinery manufacturing, and it perform well. ‌

The machine has the characteristics of advanced technology, reliable equipment, complete technology, and mature production.

Production process: Uncoiling → shearing and welding → Accumulator→ forming, high-frequency welding, deburring, cooling, sizing, rough straightening → cold cutting and sawing → roller after sawing → inspection and collection → packaging → weighing → marking → storage