Surface Signal for Flow Blockage for a Subterranean Debris Collection Apparatus

摘要

The debris collection device operates on an eductor principle with motive fluid delivered from the surface into an eductor housing inlet. The eductor outlet goes into a surrounding annular space and splits with some flow going to the mill below to direct cuttings into the passage in the housing. The cuttings remain in the housing and the flow continues through a screen in the housing passage before reaching the eductor inlet. An auxiliary inlet is normally closed and opened with a reduced flow entering through the mill. The opening of the auxiliary inlet drops the surface pressure delivered to the eductor to act as a surface signal that a plugged or low debris laden inlet flow exists.