VIBRATION DAMPER Russian patent published in 2017 - IPC E21B17/07 E21B19/18 E21B17/10 

FIELD: mining.

SUBSTANCE: vibration dampening tool for the lower part of the drill string comprises a tubular body adapted to connect each of its ends to the components of the drill string, at least one piston assy driven by the fluid. The tubular body includes an outer surface on the outer wall, a longitudinal channel and a transverse channel extending radially away from the longitudinal channel in the tubular body. The noted piston assy comprises a piston disposed in a transverse channel extending radially away from the longitudinal channel in the tubular body. The piston includes a piston body with a longitudinal axis, a distal end and a distal part. The noted distal part is located in the opening of the tubular body outer wall, and the proximal end and the proximal part. The noted proximal part is fluidly connected to the longitudinal channel of the tubular body and a peripheral ring disposed perpendicular to the longitudinal axis and around the piston body between the distal and proximal ends. Moreover, the noted ring has a maximum outer diameter that is larger than the maximum outer diameter of the piston distal part and the maximum outer diameter of the proximal part. The maximum outside diameter of the proximal part is greater than the maximum diameter of the distal part, and the noted ring has the first lateral side perpendicular to the longitudinal axis and the second lateral side perpendicular to the longitudinal axis. In this case, the piston unit comprises a piston head mounted with the possibility to be removed at the distal end of the transverse channel, and a spring chamber and at least one spring. The noted piston head comprises an opening containing the first opening portion disposed distally away from the longitudinal channel. The noted first portion of the piston head opening has a diameter configured with the size able to receive a distal end part of the piston and allowing at least a part of the piston distal part to pass through it and the second part of the piston head opening placed proximal to the longitudinal channel. The noted second part of the piston head opening has a diameter made with a size allowing to receive the piston proximal part. The spring chamber is defined by the second portion of the piston head opening and at least a part of the piston distal part and the first lateral side of the peripheral ring. The spring is located in the spring chamber. The first end of the spring contacts the first lateral side of the peripheral ring and the second end of the spring contacts at least a part of the spring chamber.

EFFECT: increased service life of the drill string, protection of the wellbore from damage, protection of equipment from breakage and increased speed of drifting.

17 cl, 18 dwg