Diaphragm compressor is widely used for the hydrogen compression because it can achieve high gas pressure without gas contamination. Diaphragms deflecting in the cavity with high pressure formed by an oil compression are the most important component i...
Diaphragm compressor is widely used for the hydrogen compression because it can achieve high gas pressure without gas contamination. Diaphragms deflecting in the cavity with high pressure formed by an oil compression are the most important component in the compressor. But the metal diaphragm repeating deflection within the cavity contour cannot have infinite lifetime. And the radial points of diaphragm don't have equal valve of strain. Therefore, it is necessary to obtain the strain of radial points to predict the damage point of diaphragm. So, the object of this study is to estimate the diaphragm's damage point and life time through diaphragm deflection test by implementing with strain gauge attached on several radial points of two different size diaphragms. In this study, strain of each radial points of diaphragm shows different values. And average radial strain, without gas compression, varies as similarly as the variation of the pressure with respect to time. With gas compression, however, that is delayed against that of the pressure. And the most largest radial strain is occurred at the near of the rim. But the most largest tangential direction deflecting point is near the middle of the center and the rim. And the most largest strain amplitude point is the 15cm point from the center of 1st diaphragm. But, the stresses of the each radial point of the diaphragm are smaller than the fatigue limit of the diaphragm material. And any crack is not observed in SEM image of operated 3,000,000cycle diaphragm. Therefore, deflection of the diaphragm in the cavity is not a factor of the diaphragm damage.