Develop technology for the screw

Screw machining center hole is locating datum, but due to the lead screw is flexible, poor rigidity, easy to deformation, straightness and cylindricity error, is not easy to achieve the pattern on the shape precision and surface quality and other technical requirements, processing must also increase when the auxiliary support. The cylindrical surface and brought into contact with the rest, to prevent the bending deformation resulting from cutting force of the workpiece. At the same time, in order to ensure the precision of locating datum in the process has arranged three grinding center hole process. Because of the screw thread is the key part, in order to prevent due to quenching crack caused by stress concentration and avoid the deformation of screw thread on the total length of grinding allowance inequality ills, thread machining processing using 'grinding' method, directly using grinding thread after heat treatment process, in order to ensure thread machining accuracy. Because the screw for single production, the demand is higher, so the processing technological process in strict accordance with the principle of process divided into stages, the entire process is divided into five stages: preparation and heat treatment in advance stage ( Procedure 1 - 6) , the roughing stage ( Process of 7 - 13) , semi-finishing stage ( Process of 14 - 23) , the finishing stage ( Process of 24 - 25) , the final processing stage ( Process of 26 - 28) 。 Arranged in order to eliminate the residual stress, the whole process to eliminate residual stress four heat treatment, machining and heat treatment after strict regulations prohibit cold straightening, in order to prevent the residual stress is produced. Deformation, in order to eliminate the process after each processing artifacts should be lifted vertically, and using the method of machining allowance layered, through multi-channel processes gradually caused in the process of machining deformation.