Section straightening machine is used for straightening ferrous metals and non-ferrous metals. It can change the straightness through the rollers extrudes sectional material. The section straightening machine used in metal processing enterprises, are mostly single machines, and used for out-line sizing straightening I-iron, channel steel, angle steel, steel rail, round and square steel etc. The machine used in large steel mills, make the sectional material repeat elastic-plastic bending deformation, eliminate the original curvature to achieve the straightness and improve the quality.

Section straightening machine can be divided into many classifications. It can be fixed pitch and variable pitch style according to different pitch style, symmetry rollers and cross rollers style according to different rollers arrangement, horizontal and vertical style according to different installing form, section material pressure straightening, aluminum section material symmetry rollers style, circular section material cross rollers style and rollers section material style according to different functions.

NHI design and manufacture the section straightening machine for more than fifty years. At present, the main types of this machine in China are manufactured by NHI, and NHI has the related reference. For example, the 350/450 section straightening machine is used for military products services for Anshan steel factory, the 550 twelve roller precision aluminum section straightening machine has wide size straightening scope and high precision for Southwest Aluminum Co. Ltd., in China. In 2012, NHI designed and manufactured two sets of 1200mm large-scale section straightening machine for one steel plant in northeast of China. It is the typical representative of modern large-scale section straightening machine.