METHOD FOR CEMENTING SHANK IN WELL AND DEVICE THEREFOR Russian patent published in 2016 - IPC E21B33/14 

FIELD: oil and gas industry.

SUBSTANCE: group of inventions relates to oil and gas industry, specifically, to methods and devices for cementing shank in open and cased well shaft. Method includes joining a shank with lower shoe, a cut device through an mounting coupling to lower end of transfer pipe string. Mounting coupling is connected with shank with possibility of synchronous rotation due to interaction of external protrusions of coupling with slots made at end of shank. Shank is lowered in well to a specified depth. Calculated volume of grouting mortar is pumped into pipe string. Launching from well mouth is performed after last portion of cement plug and flushed with flush fluid to fix it in seat of core unit of conical collars. Excess pressure is created, screws are cut and plug is moved in assembly with unit of conical collars downwards to stop ring, wherein landing cone ring is tightly seated in seat of stop ring. Grouting mortar from cavity of shank completely enters annular space. Check valve prevents entry of solution into cavity of shank of annular space. Pressure is increased to rated pressure for destruction of diaphragm with opening of holes, through which flushing liquid is washed excess solution by generating direct circulation. Method includes disconnecting from body mounting coupling with transfer pipe string, which is lifted to surface.

EFFECT: higher efficiency of method and reliability of device operation due to possibility of lowering and cementing in well with rotation for more qualitative replacement of cement grout in annular space and guaranteed disconnection of pipe string from shank irrespective of its length and in any well interval with any complexity and direction of barrel.

2 cl, 2 dwg