BOREHOLE EXPANDER JOINTED IMPACT Russian patent published in 2010 - IPC E21B7/28 

FIELD: oil and gas industry.

SUBSTANCE: borehole expander includes hollow cylindrical casing, inside which it is located hammer-stone, implemented in the form of spring-loaded from the top cylindrical pipe inside which there are located top and bottom disks with openings between which it is mounted shaft with blades on side walls and cam, joining to bottom disk. On the bottom hammer-stone is rigidly connected to working instrument by means of hollow bushing, which in top part allows radial openings and implements moving constraint with casing. In bottom part of casing it is implemented radial opening and diametral opposite to it is implemented conical opening, axis of which is inclined to the crown. In top part of casing it is located pivot with horizontal axis connected with unit of revolution, which is connected to column of pipes through sub. By means of proposed well expander it is provided destruction of breed by combined method including mechanical failure by rotating working instrument, impingement attack and washing by fluid of washer fluid.

EFFECT: productivity improvement of expansion process of well and increasing of reliability operation of equipment.

1 dwg