BORE-HOLE IMPLOSIVE SOURCE OF SEISMIC VIBRATIONS Russian patent published in 2013 - IPC G01V1/135 

FIELD: mining.

SUBSTANCE: source located in wells during their drilling during stops is used for allocation of objects in an area located in front of and around the well shaft being drilled at predicted reversed vertical seismic profiling or at borehole-to-borehole survey. A device includes a hollow housing, in the inner two-stage groove of which there installed with possibility of back-and-forth movement is an actuator piston with seals with a cleanup piston stock of implosive chamber. A cleanup piston return load is rigidly attached to upper end of the actuator piston stock. A movable sleeve with a piston and with seals is installed on the external two-stage groove so that it can move back and forth. An internal cavity under the sleeve is filled with oil and is connected in its upper part through holes and grooves to the below-piston cavity of the actuator piston of the cleanup piston. Longitudinal openings are made in lower part of the housing of reduced diameter. The chamber sleeve that is covered with a coupling from below, which is connected to the sleeve through a tight thread, is rigidly attached to the housing from below through the tight thread. A check valve preventing liquid penetration into the chamber is installed into an axial hole of the coupling. A lower load is rigidly attached to the coupling from below and provides as to the shape the vertical position of the chamber axis. Movable sleeve is rigidly attached from below to a compartment with a seismic receiver. The compartment is attached through a cable terminal to a load-carrying cable. The cleanup piston made so that it can move back and forth is sealed in the chamber sleeve and is rigidly attached with a seal from above to a hollow slide that is freely inserted and sealed in the hole of the shank rigidly fixed and sealed on the stock and restricted in axial movement with a lower flange of the shank. Inside the chamber under the cleanup piston there installed freely with a large radial gap is an anvil block that has an inner groove made in an axial hole and having the possibility of interacting with several spring-type grips rigidly fixed in lower part of the cleanup piston. Chamber openings are in an open position when the cleanup piston is in an upper extreme position. Working surface areas of the actuator piston of the cleanup piston and movable sleeve with a piston have been chosen so that pressure in an oil cavity at cable tension creates force on the cleanup piston, which exceeds force on it due to hydrostatic pressure. For this reason, at cable tension by means of a winch, first, cleanup of the chamber is performed, then, openings are opened, and hydraulic impact of liquid and anvil block against the coupling bottom takes place, and after that, the device is lifted above the working face. After the device is installed on the working face and cable weakness appears, the cleanup piston lowered to extreme lower position under action of the return load, where it is connected with spring grips to the anvil block. The compartment is provided with a seismic receiver that control the seismic station start as per the first obtained maximum signal, and after that, it transmits the reflected wave parameters received by it to the station.

EFFECT: achievement of seismic pulse repetition for many times at construction of wells during drilling breaks for performance of predicted reversed vertical seismic profiling or for borehole-to-borehole survey, at which allocations of objects are performed in the area located in front of and around the well shaft being drilled; everything is achieved without any additional work for lifting and lowering of a string using only an instrument winch; for its operation, the source does not require any supply to it of either electric energy, or hydraulic liquid.

1 dwg