WELL SCREEN AND FACILITY FOR ASSEMBLING THEREOF Russian patent published in 2008 - IPC E21B43/08 

FIELD: mining.

SUBSTANCE: well screen contains a drainage, screen meshes and a protective perforated jacket installed concentrically on a pipe. Pressure-tight shear plugs are placed on lateral surface of the pipe. Plugs are made by drawing sheet material, have hollow asymmetrical form and furnished with a thrust shoulder on the one side and a bedplate on the other side. The diameter of the plug located closer to a bedplate exceeds that of an opening made on the lateral surface of the pipe to ensure fixation of the plug in the pipe. A spliced ring made of spring steel and spliced along or at angle with the axis is installed concentrically on a stem of facility for screen assembling. External diameter of the ring is less than internal diameter of the plug. Upper end surface of the ring is equipped with an internal land-in chamfer capable of interacting with the annular bit. The latter is installed on the stem and capable of axial displacement. External diameter of the annular bit exploiting surface exceeds internal diameter of the spliced ring by the amount of plug deformation required to fix thereof in the pipe.

EFFECT: more reliable pressure-sealing of shear plugs and lowered labour intensity of mounting.

13 cl, 11 dwg