WELL FILTER Russian patent published in 2011 - IPC E21B43/11 E21B43/08 

FIELD: gas and oil production.

SUBSTANCE: well filter consists of hollow case with radial channels closed with hollow sheared caps projecting inside case, of lengthwise webbing-stringers outside case, of wire winding in stringers, and of circular support bandages rigidly connecting end surfaces of stringers with wire winding. One part of the hollow shear caps is made of flexible deformed material in form of a cylinder with external and internal conic fringes relative to the case and non-deformed material in kind of a bush. Length of the bush exceeds thickness of a wall of the case and is positioned inside the cylinder with the fringes with force facilitating radial deformation of material of the cylinder at 3-7 % of its axial deformation in a working position of the device.

EFFECT: raised reliability of well filter operation.

5 cl, 2 dwg