Abstract
The pressure method for leak test of vessels measures decrease of charged gas pressure assuming that it indicates the leak. Temperature control is important in this test. Whereas industrial standards define test duration of several days, production lines for vessels cannot accept such long test time; they can spend only several minutes for the testing. The flowrate of the leak of gas is determined by geometric parameters, pressure and gas properties. This paper shows that a geometric parameter derived from dimensions of leakage channels, which is named as leak coefficient, is known, any leak by given pressure and gas viscosity will be readily found. This paper shows methods to estimate the geometric parameter. Through experiments of leak test for a 147 L vessel, the temperature compensation was studied measuring temperature distributions in and the surface of the test vessel installing 17 thermocouples. The relationship between the measuring time and the ability of leak detection was also studied.
