Abstract: A piston with an integrated heat exchanger comprises a seal, a piston hub and a piston rod. The piston hub is further provided with a coolant reservoir and an outlet nozzle at its lateral surface. The heat exchanger integrated into the piston hub and/or the piston hub include a coolant manifold, a coolant passage communicating thereto, and a plurality of channels connecting to the coolant manifold and extending radially to the annulus. Said heat exchanger provides enhanced efficiencies of heat-exchange and debris-flushing.

Abstract: A piston with an integrated heat exchanger comprises a seal, a piston hub and a piston rod. The piston hub is further provided with a coolant reservoir and an outlet nozzle at its lateral surface. The heat exchanger integrated into the piston hub and/or the piston hub include a coolant manifold, a coolant passage communicating thereto, and a plurality of channels connecting to the coolant manifold and extending radially to the annulus. Said heat exchanger provides enhanced efficiencies of heat-exchange and debris-flushing.

Abstract: In a pump having a cylinder liner, there is a piston therein, a seal around the piston and rear wearband around the piston body to align the piston within the liner. An elastomeric seal ring is in sealing and sliding contact with the liner. A gap filler, with minimal axial creep and controlled radial creep, abuts the rear surface of the seal and maintains continuous contact with the liner thereby continuously closing the extrusion gap between the gap filler and the liner as the liner wears. The wearband has a plurality of angled grooves longitudinally traversing it. Abrasive particles are directed within and through the grooves in the wearband while a source of liquid is communicated into the piston body, through water channels in the gap filler and through the flowpaths in the wearband to create a vortex action which washes the liner wall. The wearband insures no metal to metal contact between the piston and liner and provides a constant piston gap between the metal piston and liner.

Abstract: A chemical cutting apparatus and method for cutting objects in well bores such as, for example, tubing in the bore of an oil or gas well. The apparatus is properly positioned relative to the object to be cut by means of a casing collar locator and an igniter is fired, which in turn activates a gas generator. Pressure from the gas generator axially displaces a slidable piston having one or more wedges pivotally connected thereto. Movement of the piston both pivots and extends the wedge, thereby bringing the wedge into contact with the object to be cut and anchoring the apparatus relative to the object to be cut. The pressure generated in the gas generator is communicated through a passageway in the slidable piston and forces a chemical cutting agent into a chamber containing a reactant. The reaction of the chemical cutting agent and reactant increases the pressure and temperature within the chamber thereby displacing along the axis a second slidable piston.