Abstract:Elbow is the key component of the electric torque wrench, its performance is an important factor to determine the control accuracy, transmission efficiency and stability of the wrench. In order to ensure the performance of the elbow electric torque wrench, the measurement and control system of the elbow test machine was designed. Before the assembly of the whole machine, the performance of the elbow was tested, and the torque, speed and transmission efficiency of the elbow were tested, so as to realize the quality inspection and quality management, and the design, processing and assembly level of the elbow was improved. Based on Siemens S7200 smart PLC and Kunluntongtai TPC7062Ti touch screen, the measurement and control system was designed, and the different working modes, data processing and data monitoring were realized. Through the test, the system has friendly interface, high degree of automation, high test efficiency, and it’ s measurement and control function meets the elbow test requirements, which improves the intelligent manufacturing level of the elbow electric torque wrench.