INTERNAL MECHANICAL PIPE CUTTER Russian patent published in 2014 - IPC E21B29/00 

FIELD: mining.

SUBSTANCE: device includes a hollow adapter, a hollow housing, a hollow shaft, an anchoring assembly including a spring-loaded ram holder arranged in the middle part, provided with longitudinal inclined slots and three rams on the surface, three friction rams with a group of screw cylindrical springs, and a wedge device. An external housing of the adapter is made in the form of a cylinder with a cross section. An internal housing - a cylinder having outside diametre for inside diametre of the external housing. Rams are installed in openings of the housing and the ram holder and provided with teeth in the form of polyhedrons on front surface. The ram holder is made in the form of a straight hollow cylinder, through longitudinal slots - openings for rams are made in the centre of this cylinder. Cutters are arranged in the cutter holder and consist of a working cutting part and a shank in the form of an asymmetric rhomb. The cutter holder is made in the form of a straight cylinder with longitudinal slots throughout the cylinder length; spring-loaded cutters are arranged in three of them, and H-shaped tie rods are arranged in the other three of them. Below the cutter holder a shaped sleeve has a wedge part contacting with its inclined surface to the cutter. In the middle part there arranged in a detachable housing-sleeve is an assembly with two sliding bearings. The lower end part of the external housing of the adapter is T-shaped. The hollow shaft has radial through holes in the lower part.

EFFECT: improving reliability, processibility and maintainability.

9 dwg