Skip to content

Springback Compensation Methods and their Application in Roll Forming of Metal Profiles

Roll forming is a well-established production process used in the manufacturing of metal profiles. However, the final shape of the formed product often deviates from the desired shape due to the spring back phenomenon. Springback is a result of elastic deformation and occurs when the internal stresses of the material cause it to return to its original shape after unloading. The higher the elasticity of the material, the more severe the spring back effect.

Springback not only affects the dimensional accuracy of the formed product but can also lead to tool wear, which shortens the service life of manufacturing equipment. Thus, it is necessary to compensate for spring back during the roll forming process to ensure the desired product shape and reduce tool wear.

Top 4 spring back compensation methods

aluminum bending machine

There exist various springback compensation methods that can be used for roll forming applications. In this article, we will discuss some of the most commonly employed ones.

Geometric Compensating Method

This method compensates for springback by bending the workpiece into an over-bent shape initially. The over-bent shape compensates for the anticipated springback, producing the desired final shape. This method is not suitable for systematical compensation because of the variations that occur in the rolling process.

Pressure Compensation Method

In this method, additional pressure is applied to the workpiece during the lower roller bending section to reduce the spring back. By increasing the pressure, the additional plastic deformation in the workpiece can weaken the elastic recovery, effectively reducing the springback. The pressure is generally applied with a hydraulic cylinder or a pneumatic cylinder.

Tensioning Compensation Method

The tensioning compensation method achieves springback compensation by applying tensioning forces to the outside of the workpiece while it is being bent around the rollers. The forces decrease the effective bending radius in the central area and thus reduce the spring back effect. This method is advantageous in being able to use rollers with a larger radius, which can result in an improved quality of the formed product.

plate rolling machine
plate rolling machine

Combined Compensation Method

This method is a combination of the previous three methods. It is designed to compensate more effectively for the springback phenomenon, especially in complex roll forming profiles. It includes the pre-bending of the workpiece, increasing the pressure applied during the rolling, and applying tension around the profile.

In addition to these compensation methods, several algorithms exist for predicting the amount of springback that occurs during computational simulations. These algorithms are used in conjunction with the above methods to optimize the compensation process.

TABLE OF SPRINGBACK COMPENSATION METHODS:

MethodAdvantageDisadvantage
GeometricEasy to implementNot suitable for complex profiles
PressureApplicable on large diesNeeds pressure system
TensioningGood for large radiiNot efficient for tight radii bends
CombinedCompensates effectivelyComplex process, needs modeling

Final Words

Roll forming of metal aluminum profiles is a widely used process. However, it often experiences the springback phenomenon due to the elastic properties of the metals used. Fortunately, several springback compensation methods are available that can be employed to reduce the effect of springback on the final shape of the formed product. By understanding and carefully selecting the appropriate compensation method, manufacturers can optimize the roll forming process and improve the quality and accuracy of the final products.