DEVICE FOR STEPPED WELL CEMENTATION Russian patent published in 2005 - IPC

FIELD: oil production, particularly for well completion and cementation thereof.

SUBSTANCE: device has body and case with cementing and process orifices, main bush with baffle, differential bush with fixing members installed to perform axial movement between case and body, cementing plugs, upper and lower adapters. Device is provided with additional bush arranged inside lower adapter with baffle having lesser diameter than that of main bush baffle. Main baffle is arranged between cementing orifices formed in body and case, which are at least partly overlapped and process orifices, which establish communication between tube space and annular space. The annular space is defined by mating inner surface of differential bushing and outer surface of the body. Differential bush is connected to resilient member by upper end thereof. Annular space is sealed by sealing rings to prevent outer pressure action.

EFFECT: increased reliability and reduced metal consumption.

2 cl, 3 dwg