Research On Testing System Of Electromagnetic Valves For Gas Medium

Inspection of the solenoid valve to ensure product quality is an important aspect in solenoid valve production. In accordance with performance requirements, the thesis develops a suit of testing system of electromagnetic valves for gas medium. The system could perform action test, airproofing test, leakage test and life-span test for electromagnetic valves. The thesis has three parts as follow:The first part is to design the project and the systemic makeup of testing system of electromagnetic valves for gas medium. Leakage testing by gas pressure is applied in the system and bang-bang combinated with PID is applied to adjust systemic pressure. Then the thesis designs the control system and chooses the main elements, including air compressors, gas storage, transducer, pressure and flux sensors. So this part has performed the substantial parts of testing system for electromagnetic valves for gas medium.The second part is to design the program in LabVIEW and CX—Programmer, which is the programmable software of PLC. According to demands of testing system, some flows have accomplished in the thesis, including process of pressurizing pipelines, action test, airproofing test, leakage test, life-span test and general test. The interface and program in LabVIEW have been completed, and some function modules have been illuminated, for example, data acquisition, data storage, filling-in valve’s parameters and monitor interface. The ladder program in CX—Programmer has been completed, including I/O resource assign, the design of tasks and subprogram. In the later debugging in laboratory, all these programs run well, so the testing system could control automatically.The third part analysis the pressure and flow characteristics of the pipe. With all the pneumatic components as well as the specific path of the pipeline, the flow capacity of the system is researched. At the same time compared with the curves obtained by the experiment, the viability of the design is proved, and due to the differences of the curves and the theory some modification is proposed to reached a more accurate result.