3-Roller Bending Machine with Prebend for Structural Steel

Application-Specific Precision in Prebend Bending

The 3-roller bending machine with prebend function is engineered for structural steel applications, where accurate cylindrical forming is required without end deformation. This pre-bending capability ensures that no flat area remains at the sheet edges, significantly improving roundness and weld seam precision. It is especially critical for fabricating steel silos, pressure vessels, transmission pipes, and architectural columns where dimensional accuracy directly impacts assembly and integrity.

 

Control Accuracy and Material Compatibility

The hydraulic 3-roller system operates with synchronized positioning through an advanced proportional valve system, ensuring tight control over plate alignment and pressure distribution. The side rolls are hydraulically adjusted with automatic compensation to accommodate mild steel, stainless steel, and alloy sheets of varying thicknesses. The pre-bending function minimizes material springback and eliminates the need for excessive post-processing or trimming.

 

Benefits of Prebend Functionality in Heavy Industry

In structural steel fabrication, edge accuracy is critical for seamless cylindrical joints. The prebend mechanism allows operators to bend the leading and trailing edges of the plate prior to full roll forming, eliminating flat spots that occur in standard 3-roll systems. This results in:

Improved circularity and dimensional consistency

Stronger weld joints due to precise edge alignment

Reduced labor for rework or filler operations

Enhanced process efficiency for large-diameter pipe forming

 

Structural and Mechanical Design Advantages

This machine utilizes induction-hardened alloy steel rollers, supported by a high-rigidity frame with finite element analysis (FEA) verified load paths. The torsion shaft link mechanism ensures parallel roller movement, while the digital readout system gives real-time feedback on roll positions. The machine is equipped with a centralized lubrication system, automatic side supports, and optional cone-bending capabilities.

 

Integrated Automation and Digital Control

The system features NC or CNC controllers with programmable prebend cycles and memory storage for material parameters. Automated positioning and roll pressure adjustment allow for rapid switching between different bending profiles and materials. This functionality not only shortens cycle time but also improves repeatability and operator safety, especially in high-volume fabrication settings.

 

FAQs:

What is the prebend function in a 3-roller bending machine?
The prebend function enables the machine to bend the leading and trailing edges of a metal sheet before full roll forming. This minimizes flat zones and improves the circular accuracy of the finished component.

How does a 3-roller prebend machine improve weld seam quality?
By pre-bending both ends of the plate, the machine ensures tight edge contact during rolling, which reduces gaps and misalignment at the weld seam, resulting in stronger and more reliable joints.

Can the 3-roller prebend machine handle thick structural plates?
Yes, it is engineered to process thick mild steel or alloy plates up to 80mm (depending on model), making it suitable for structural components such as bridge supports, tanks, and large-diameter pipes.

What is the difference between a prebend and a non-prebend plate roller?
A prebend roller can reduce the unbent flat area at the sheet ends, which is not possible with standard 3-roller machines. This leads to better accuracy, reduced waste, and lower finishing requirements.

Which industries use prebend-capable 3-roll bending machines?
They are widely used in structural steel fabrication, shipbuilding, boiler manufacturing, pressure vessel production, and oil & gas pipeline construction, where cylindrical precision is crucial.

Looking for a reliable 3-Roller Bending Machine? Contact us today to explore our extensive range of Precision Lathe Reliable Pergormance and find the perfect solution for your production needs.

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