The Venturi Junk Basket is used to remove debris from the wellbore.
The Venturi Junk Basket operates by pumping fluid through external nozzles in the tool to an internal debris chamber. The increase in fluid velocity at the nozzles results in a reduction of pressure in the Venturi chamber. This pressure differential creates a circulation path through the tool carrying loose debris into the debris chamber.
A filter screen in the tool prevents debris from blocking the flow path in the Venturi chamber. When circulation through the tool is stopped, “finger catches” at the bottom of the tool close preventing solids from falling back into the wellbore. The capacity of the debris chamber can be increased by adding wash pipe extensions.
The Venturi Junk Basket can also be ran with a Wash Over Shoe fitted to the bottom of the Venturi. When used in conjunction with a down-hole motor, this provides the facility for debris removal in operations such as milling or washing over a fish.