Application

TVG-U wide-range hydraulic internal cutter is designed to cut and retrieve tubing during well intervention. 

Design

The cutter consists of a crossover for connecting the cutter to motor shaft, body with insert knives, a mandrel, a spring, a retainer ring, a centralizer sleeve, a mandrel extension, a centralizer drag spring, a sub, an O-ring and a jet. 
Rotation of the cutter and concurrent pressure increase in the chamber force the mandrel to drive knives outwards from the body slots. The spring and retainer ring enable smooth and uniform feed to the knives. 
When tubing has been severed and pressure has dropped, the piston goes back to its initial position, retracting knives inwards the body slots. Installed at the bottom, the centarlizer diminishes play of the cutter during its operation.The centralizer consists of three drag springs attached with screws. While running-in, the drag springs push against the walls acting as a plain bearing.