CNC Sawing System Research Of Metal Cutting Band Sawing Machine

Metal cutting band sawing machine is mainly used for cutting all kinds of metal material which serves as the starting point of metalworking has becoming an important part in the process of metalworking. Currently, the domestic band sawing machine products have some problems, such as the low efficiency, the low level of CNC and so on. In view of this, the paper started with the basic sawing process of band sawing machine and the results of cutting force test, purposed on improving the sawing efficiency of metal cutting band sawing machine, put forward the CNC sawing theory with constant power and constant cutting force in sawing process, researched the control strategy of cutting speed and cutting force on horizontal-double columns metal cutting band sawing machine with the control scheme of open-loop and closed-loop, designed and manufactured the CNC sawing system, made the cutting force to be constant and motor power to be fully utilized while sawing different width workpieces, did experimental research and verification last.The main work of the paper is as follows:1. Analyzed the factors affecting the cutting force in the sawing process of band sawing machine, proposed the CNC sawing theory of constant power and constant cutting force, researched the two overall schemes of CNC sawing system based on stepper motor with conventional throttle and based on proportional flow control valve, established the mathematical model.2. The paper adopted V/F frequency control theory to achieve constant cutting speed control; Applied fuzzy PID control theory to hydraulic feed system of band saw machine to achieve constant cutting force control, and designed a fuzzy PID controller based on Matlab which is suitable for CNC sawing system of band sawing machine, carried out simulation of constant cutting force control by Simulink. Designed software and hardware of CNC sawing system based on PLC, mainly including sensors, inverter, HMI, PLC, software designing and so on3. Manufactured the CNC sawing system based on horizontal-double columns metal cutting band sawing machine, experimented with rectangular cross workpiece which section width is unchanged, circular cross workpiece which section width is continuously varying and L-shaped cross workpiece which section width is step mutation; Verified the feasibility and sawing effectiveness of CNC sawing system through the experimental data comparison by constant feed rate sawing and CNC sawing; Discussed the pros and cons of the two schemes through the experimental data comparison by the scheme based on stepper motor with conventional throttle and the scheme based on proportional flow control valve.Sawing experimental data show that the CNC sawing system of metal cutting band sawing machine which the paper designed and manufactured improve sawing efficiency and the level of CNC, has great engineering value.