Abstract: This application is directed to methods of using pressure balanced mud motors. The mud motor includes a power section to rotate a passageway housing and propel fluid through a passageway disposed in the passageway housing. The mud motor can also include a roller bearing assembly and a drive shaft assembly to improve the life and efficiency of the pressure balanced mud motor.

Abstract: This application is directed to a pressure balanced mud motor and a method of using the mud motor. The mud motor includes a power section to rotate a passageway housing and propel fluid through a passageway disposed in the passageway housing. The mud motor also includes a drive shaft assembly that allows for easy replacement of parts.

Abstract: This application is directed to a pressure balanced mud motor and a method of using the mud motor. The mud motor includes a power section to rotate a passageway housing and propel fluid through a passageway disposed in the passageway housing. The mud motor also includes a roller bearing assembly to better handle the operational conditions and stresses involved with the use of a mud motor downhole.

Abstract: This application is directed to a pressure balanced mud motor and a method of using the mud motor. The mud motor includes a power section to rotate a passageway housing and propel fluid through a passageway disposed in the passageway housing. The mud motor also includes a hydraulic apparatus for balancing a pressure drop experienced across a bearing assembly due to frictional flow of fluid through the passageway.

Abstract: This application is directed to a pressure balanced mud motor. The mud motor includes a power section to rotate a passageway housing and propel fluid through a passageway disposed in the passageway housing. The mud motor also includes a hydraulic apparatus for balancing a pressure drop experienced across a bearing assembly due to frictional flow of fluid through the passageway.

Abstract: An electric coupling for two electric circuits in a well includes an electric contact and a contact receiver connected to respective ones of the circuits so that a contact/receiver pair is formed when the contact and receiver are moved together The receiver is sealed by a sealing member. The sealing member is disposed so that it is penetrated by the contact when the contact and receiver are moved together. A coupling including two such pairs is preferably used to connect two electric wires in the well to form a current conductive loop linking two electric coils. One of the coils is adapted to be moved in the well relative to the other coil which is adapted to be fixed in the well. In a preferred embodiment, one coil is on a wireline tool and the other coil is on a downhole tool.