NEAR-BIT EJECTOR PUMP Russian patent published in 2018 - IPC F04F5/10 

FIELD: pumps.

SUBSTANCE: pump is designed to reduce bottom-hole pressure, reduce pollution (colmation) of the reservoir during the initial opening. Pump includes a housing with external through channels through which the annulus above the pump is in communication with the space below it, central trunk, dividing partition, ejectors located in the upper part of the body around the central trunk and communicating with it to the partition by high-pressure channels, mixing chambers connected through low pressure channels to the central trunk after the partition, and diffusers connected hydraulically to the annular space. Pump casing is designed as a composite vane calibrator, on the outer surface of which an adjustable choke is installed in the restrictive window with the possibility of overlapping the casing through channels of the casing below the diffusers, the choke is made in the form of an elastic rubber cuff, the internal cavity of which is connected to the central trunk of the body with high and low pressure channels, respectively, before and after the partition, the internal cavity is connected with one or another channel by displacing the components of the calibrator depending on the axial load acting on it.

EFFECT: technical result – increased mechanical drilling speed.

1 cl, 4 dwg