A New Multi-cutting Tools CNC Machine's Design And Research

With the increase demand of Oil Country Tllbular Goods(OCTG),a situation that OCTG threading machines are imported from abroad and designed inland has been arisen.As the imported machines are expensive and the domestic machines cannot meet the production requ-irement currentl,We designed a multi-tool CNC Pipe Thread Lathe to meet production needs.This research roots in the "QK1260 NC multible tools pipe thread lathe" subject, which was entrusted by a institute to Lanzhou university of technology. Now, this lathe is under mannufacturing and patent arising from this research issues is under application,In this thesis, focused on the design of Mechanical System, the following problems are discussed:(1)The defection in the machining of large aliber-long pipe thread on normal equipment is analysised, technical difficulties are identified, finally, a lathe with still workpiece, composie movement of cutting and feeding, and simultaneous multitools cooperation is conceived, which provides higher efficiency.(2)Whole scheme of the machine Was designed in this paper.Tlle layout and the mac-hine parameters such as overall dimensions.spindle speed and maximum strokes of X and Z axis were determined;(3)Focused on the design objective and the transmission demand, key drive parts in the headstock including principle subassembly, gear drive groups, feeding mechanism and so on; and facing head assembly;(4)The type selection and calculation of servo system were completed.The linear motors as feed mechanism were configured;the servo drives and encoders were selected according to the motor power and required precision.The cutting force Was estimated by the formula of screw cutting force,and the cutting power Was derived according to the computed cutting force.At last,a proper electro-spindle Was determined based on the spindle speed and computed cutting power.(5) Finally, Ansys finite element software key components:spindle, spindle box for analy-sis of dynamic characteristics to predict the machine when we work force and deformation. According to forecasts the size of the original design optimization to determine the optimal size of parts.