HOLE FILTER Russian patent published in 1999 - IPC

FIELD: exploitation of oil and gas fields, applicable for equipment of casing production strings with filters at pumping drilling mud down the bore-holes. SUBSTANCE: the hole filter comprises a tubular casing with holes closed with plugs, each containing a bush with a core. The casing is furnished with centering mounts uniformly located over its entire length. The plug bushes are rigidly connected to the casing, and the cores-to the bushes. The cores are made concave from the inner surface and cone-shaped and projecting from the outer surface of the casing; the plug cores are made of material destructible at chemical action. They are made concave from the casing inner surface for self-sealing of the joint of the cores with the bushes under the action of pressure at a pressure test of the production with the filter. The cores project from the casing outer surface for operation of these cores as bullets for destruction of cement stone shot by excess pressure in the production string at disturbance of coupling of the cores with the bushes at chemical action. EFFECT: simplified design of the filter, enhanced quality of cementation and development of productive pool. 1 dwg