Research And Application Of Self-discharge Detection For Li-ion Battery

High pressure FRP pipe is a composite pipe with many advantages, such ashigh strength, corrosion resistance, light weight, small frictional resistance, anddesignable, which make it has a wide application in the fields of oilfield,petrochemical industry, municipal administration, environmental protection.High pressure FRP pipe hydraulic testing machine is important which use to testwhether the pressure resistance of pipes is standard. In order to guarantee thereliability of high pressure FRP pipe, avoiding the economic loss because of theaccidents such as poor pressure resistance. Every high pressure FRP pipe shouldbe strictly tested before using.The paper, aiming at the technological requirements of high pressure FRPpipe hydraulic test, design the control system of high pressure FRP pipehydraulic testing machine. Design the hydraulic test machine with four automaticcompression working modes, and the machine include of loading and unloadingframe, support frame, pipe line, water channel,using two high voltage variablefrequency water pumps to work. The structure of four stations of hydraulictesting machine is designed, the touch screen as host and the OMRON PLC asslave, make the hardware control system. The software control system ofhydraulic testing machine is designed, the upper computer program of the controlsystem with the functions of human-computer interaction, can dynamic responsethe change of pressure, the time of working and machine failure alarm, etc. Thelower computer divides into automatic control and manual control, real-timemotion control and logic control, etc. Using the control methods of limiting theoutput value of PID and structural change of PID, and four kinds of automaticways to work, make the different kinds of pipes and different pressure range totest. Using two high voltage variable frequency water pumps, together andindependent to work, to overcome the defect of traditional test machine with only adapt narrow hydraulic pressure range and few types of pipes. The hydraulic testmachine guarantees the precision of pressure.Lots of experiments are made in factory, the results show that, the controlsystem of high pressure FRP pipe hydraulic testing machine, can test the pressurefrom5MPa to30MPa, the diameter from40mm to300mm. Hydrostatic testingmachine is easy to operate, high degree of automation. The working efficiency,the accuracy, and the stability meet the actual production requirements.