Paper: The Equalizer A New Concept In Downhole Drilling Tools

The Equalizer is a totally new concept in downhole drilling string accessories. The principle of the device is much like that of a hydraulic jack as it acts as a resilient coupling between the drill string and the rock bit. Unlike spring loaded shock subs, the tool does not store energy. A series of hydraulic pistons is energized by the pressure drop generated across the jet nozzles of a rock bit by the surface mud pressure system. The mud system pressure drop is then internally utilized by the tool to provide a fluid coupling or "fluid cushion" between the bit and the drill string. At the same time, a constant weight is being transmitted to the bit. The tool has increased bit life and penetration rates, while substantially reducing shock damage to drill string components.