Straightening is a process to eliminate radial bending of shaft, pipe and rod parts or the bending of stainless steel pipe fittings related to the work piece.The traditional straightening methods mainly include press-point straightening, roller straightening, roll straightening and so on. It is usually used in the production and manufacture of stainless steel pipe fittings or the repair of stainless steel pipe fittings, and it is most used in the processing of precision parts of shaft and pipe.The theory of straightening technology mainly studies the process flow or steps to eliminate or reduce the bending deformation caused by the parts in the process of machining, so as to ensure that the parts meet the design requirements.

At present, the research of straightening process theory is mainly based on improving the traditional straightening process method, analyzing the factors that affect the straightening accuracy and straightening efficiency of parts, perfecting the theoretical mathematical model of straightening, improving the straightening process, and on this basis, developing automatic straightening equipment suitable for the domestic market.