Research On Online Data Measurement System Of Friction Stir Welding

With the continuous development of friction stir welding technology,the application scenarios of friction stir welding technology are becoming more and more extensive in the petrochemical field.Obtaining better weld quality and coping with more complex welding environments have become the research goals of friction stir welding.Friction stir welding is a kind of pressure welding,and the welding pressure,spindle torque and welding temperature during the welding process are important parameters to explore the welding process and improve the quality of the weld.Since these parameters are not directly available during friction stir welding,it is of great significance to study and develop a data measurement system that can synchronously collect key welding process parameters.Up to now,the friction stir welding data measurement system is mostly one signal acquisition,large equipment volume and the wired acquisition method make the welding environment more complex.The small-volume wireless data measurement systems that can simultaneously collect torque,pressure and temperature is of great significance to the development of friction stir welding.Based on the existing friction stir welding equipment,based on the basic theories of finite element calculation,material mechanics,data acquisition and communication,and relying on numerical simulation calculations,digital signal conditioning,Bluetooth data transmission and other technical means,this paper researches and develops a set of stirred friction welding online data measurement system,which realizes high-precision data acquisition and wireless high-speed data transmission in a large range.The system is composed of two parts: the lower computer data acquisition system and the upper computer information receiving and display system.Among them,the data acquisition system of the lower computer adopts STC15W408 A processor,which can realize the acquisition of torque,pressure and temperature signals,information processing,intelligent early warning,Bluetooth transmission,zero drift compensation and parameter calibration.The host computer information receiving and display system adopts QT as the software development platform,and through independent programming,it can realize functions such as serial port identification,data management,curve drawing,error analysis and so on.The Bluetooth receiving module is designed for the high-speed transmission of wireless signals.Experimental test results show that the system can achieve 0-20 KN downforce,0-100 Nm spindle torque,0-700℃welding temperature range data measurement.Its detection accuracy is 0.1 KN,0.2 Nm,and 1℃,respectively.The data transmission and display update rate reached 0.1S,which meets the requirements of the friction stir welding process under normal working conditions.