Patent ID: 6592126
Filing Date: 2003-07-15
Classification: F16J,G01M,Y10T

Abstract:
In a mechanical seal having a gland surrounding a rotatable shaft in radially spaced relation therewith, said mechanical seal including a seal arrangement cooperating between said gland and said shaft to sealingly separate first and second regions disposed along said shaft, said first region being a process fluid chamber containing a liquid process fluid, and said second region being a gland chamber disposed adjacent said seal arrangement so as to receive fluid leakage of said process fluid from said second region, said gland further including a drain port which is in open communication with said gland chamber for receiving any said fluid leakage, comprising the improvement wherein said mechanical seal includes a leak detector assembly which includes a detector housing having a leakage chamber and an inlet passage, said inlet passage being in open communication with said drain port and said leakage chamber to permit any of said fluid leakage to flow therethrough into said leakage chamber, said leak detector assembly further including a fiber optic sensor unit which comprises a sensor probe that is mounted on said detector housing, said sensor probe including a sensor tip which is positioned to detect the presence of said fluid leakage within said leakage chamber through contact of said sensor tip with said fluid leakage, said fiber optic sensor unit including a control unit and said sensor probe being operatively connected to said control unit, said sensor tip detecting a refraction index of fluid material surrounding said sensor tip wherein said fiber optic sensor unit generates a first signal corresponding to a refraction index of a surrounding fluid material within said fluid chamber which surrounds said sensor tip in contacting relation therewith during normal mechanical seal operation and generating a second signal corresponding to a refraction index of said fluid leakage within said leakage chamber when said fluid leakage contacts said sensor tip, said control unit detecting said first and second signals and generating an output signal which changes when said fiber optic sensor is contacted by said fluid leakage adjacent said sensor tip and indicates a flow rate of said fluid leakage.