Research And Design Of Air Leak Testing System

Air leak testing technique has been applied in many fields,such as automobile,oil piping,aviation,electricity and family facilities etc..There are many air leak testing methods ,according to different principles,it can be divided into:air bubble leak testing, pressure leak testing,halogen leak testing,helium mass spectrum,sink and chemistry leak testing and sound wave testing etc..Pressure leak testing is usually used in industry,it is a technology that by testing the changes of the status of the gas.Pressure leak testing usually can be divided into direct pressure leak testing and differential pressure leak testing.Direct leak testing has the advantages of economic,simple,convenient,useful etc.,but it has low accuracy,and it is vulnerable to the impact of external factors.So,it is always not used in high precision occasions.And it is widely used as its low price.Differential pressure leak testing has the similar testing process with the direct pressure leak testing.Although it has higher price and more complicated structure,it has high testing precision and small impact by external factors.In this paper,for economic,practical,concise and other considerations,we do research and design on direct pressure leak testing.The system is controlled by 51-MCS processor that gets and processes the data,controls the valve,so that conquers the impacts by the man-made.And it includes keyboard inputting,digital display etc..This system's physical design includes hardware design and software design.Hardware design mainly includes single chip microcomputer peripheral circuit design,sensor circuit design,ADC circuit design,keyboard circuit design,LED circuit design etc..The software design mainly includes main program design,key-press interrupt program design,display program design,ADC data getting and processing program design,E2PROM program design etc..Meanwhile,this paper will do some analysis and research on the factors that impact the precision of direct-pressure leak testing.And this paper will do some research on how to decrease the time of testing and realize fast testing,then bring forward the definite solutions.