DEVICE FOR WELL CLEANING FROM SAND PACK Russian patent published in 2012 - IPC E21B37/00 

FIELD: oil and gas production.

SUBSTANCE: device includes cross-over module, hollow housing tightly connected to the outer impact bit at the bottom part, operating chamber located in the hollow housing and damage mechanism coaxially mounted in the hollow housing. The outer bit is equipped with end teeth and has inclined radial holes directed upwards. The hollow housing is spring-loaded in relation to cross-over module. Damage mechanism includes hollow connecting rod, internal impact bit and valve installed with the possibility of restricted axial movement. The internal bit is fixed at hollow connecting rod, equipped with end teeth and has inclined radial channels directed downwards. The hollow unloading rod is tightly connected to the cross-over module and has two rows of through longitudinal slots. Operating chamber consists of three inserts welded in elastic elements with common axial channel. The upper insert has end threaded hole with oil cup installed in it and inclined channel directed towards the hollow housing. The inner surface of the lower insert in the middle part is made in a form of a saddle for damage mechanism valve. The holes of outer bit have length that provides their combination with the channels of internal bit in the end lower position of damage mechanism. The valve is installed in the cavity of unloading rod and has two rows of through longitudinal slots.

EFFECT: increase of device operation efficiency, reliability.

5 dwg