Witness drain valve

• Main Author: WILCOX DAVID E
• Format: Patent
• Language: English
• Published: 03.06.2003
• Edition: 7
• Subjects: ACTUATING-FLOATS; BLASTING; COCKS; CRANKCASE VENTILATING; DEVICES FOR VENTING OR AERATING; ENGINE PLANTS IN GENERAL; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; LUBRICATING INTERNAL COMBUSTION ENGINES; LUBRICATING OF MACHINES OR ENGINES IN GENERAL; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; STEAM ENGINES; TAPS; THERMAL INSULATION IN GENERAL; VALVES; WEAPONS

For regulating engine exhaust and for environmental reasons, aircraft users are restricted from expelling engine fluids from engines onto airport ramps. All such fluid must be collected and subsequently burned or properly disposed of. The present invention installs witness drain valves in the drain lines between seal cavities and environmental collector tank. The witness drain valves have a small reservoir that will retain a known volume of fluid. As fluid passes from a leaking seal to the collector tank, a small sample is captured in the witness drain valve. Once the witness drain valve reservoir is full, the leaking fluid then flows on to a collector tank, which is also provided. During regular engine maintenance, technicians push on a spring loaded drain valve located on the witness drain valve reservoir. If fluid is detected, the seal is beginning to leak, and corrective maintenance may be scheduled while the leak rate is still within operational limits.