| The flash butt welding machine is a high efficiency and steady welding equipment. At present the band saw blade flash butt welding machines used in China are mainly imported abroad. After assimilating modern overseas technology and equipment of welding machine, The band saw blade flash butt welding machine automatic control system is studied and designed. It is conducive to enhancing the modern technical level of band saw blade flash butt welding equipment, and is also great significant to making the band saw blade flash butt welding equipment in our country.The control system is composed of Mitsubishi FXIN PLC and thyristor voltage regulator, with other ancillary equipment (such as control switch, close to switch, micro switch, servo drives, etc.) According to the principle of flash butt welding, using the servo drivers, thyristor regulations and combined with the special displacement curve of the cam to control of flash butt welding process, ensure the quality of the saw blade welding.The control system adopted PID control technology, thyristor regulating technology and infrared detection technology to automatic control the tempering temperature, and realize the automatic monitoring of band saw blade heat treatment. The touch screen displays curves of heat treatment temperature, welding parameters and operating hints, and the welding process parameters can also be set up and modify by the touch screen,simplifies the control and makes a comfortable environment.Based on the development of control system, through the experimental research method to proof its the rationality and validity. By orthogonal experimental design method, and taking the comprehensive evaluation of flash intensity, weld slag stacking and weld shape integrity as test indexes, process parameters including flash speed, Welding voltage, upset forging pressure, Welding duration are optimized by using range and variance analysis methods,then the optimal process parameters combination is determined. The results show that the welding voltage had a great effect, then welding duration and upset forging pressure, and flash rate is minimal. Repeat tests are carried out using optimized process parameters combination, for the welded joint with mechanical properties testing and microstructure observation, the results showed that: in accordance with the best combination of welding level, its tensile strength close to the parent metal tensile strength of 90%.Studies show that the entire system anti-interference capability, the control software satisfies the flash butt welding process control request, so in some degree it meets the control requirements of mechanization and automation of flash butt welding technological process, which is of extremely vital significance to stabilize welding quality. |
PDF Full Text Request