Straightening machine is a heavy equipment used in metal working industries. Its function is to straighten various type of metal objects like rolled beams, channels, flats, angles, pipes, rods, wires, stud, strips etc. This process is done by using a well-proven rotary straightening method. These machines are available in different models, sizes and configurations to meet the customer’s requirements. These are designed to provide maximum performance and accuracy. They are also made to meet the industry’s safety standards.
The machine is able to achieve the desired straightness in one pass of the product. In this way, the production time is reduced and the quality of the product is improved. It also helps to increase the yield of the product. Hence, this machine is considered as a very important tool in the metal processing industry worldwide.
There are two main types of straightening machines-straighteners and corrective levelers. A straightener removes coil set by passing the material through a series of rollers. A corrective leveler, on the other hand, uses a combination of stretching and rolling to re-flatten the metal strip. This is necessary to overcome the problems caused by the inherent issues with hot rolled coils, such as warp and buckling.
With the wide range of potential variations in material thickness and width, no single straightener is capable of satisfying all application requirements. In order to address this, most straighteners are equipped with a ‘zero’ or ‘home’ setting for the work roller depth. This is defined as the point at which the upper work roller is tangent to the lower ‘fixed’ bank of work rollers. The ‘zero’ position can be achieved with any number of upper work rollers but is most often achieved with five to eleven work rollers.
Since each metal has its own specific yield point, it is important that the straightener be able to adjust the height of each roller according to the material being processed. This is why many straighteners offer computer or manual adjustments with readouts, making it simple and easy to obtain the desired result.
Another issue that must be addressed is the fact that different materials require a variety of roller diameters and center distance spacings. Thicker materials typically require larger-diameter rollers while thinner metals can be straightened with smaller-diameter work rollers. Moreover, the amount of pressure exerted on the work rollers by back-bending the material requires a certain amount of space between them in order to prevent excessive deflection of the system. This is why most straighteners are designed with ‘back-up’ or support rollers to help reduce the stress on the work rollers and minimize the possibility of damage. The size of the back-up rollers is typically determined by the overall machine dimensions and maximum material thickness specification.