Abstract: A drive shaft assembly for a down hole drilling motor is provided. The drive shaft assembly includes a drive shaft having a first end portion engaging a first housing and a second end portion, engaging a second housing. The first end portion and the first housing form the first constant velocity joint and the second end portion and the second housing form the second constant velocity joint of the drive shaft assembly. Each end portion including a base surface having a pair of prongs extending away from the base surface and a cylindrical side wall having a plurality of ball bearings held in a plurality of circumferentially spaced pockets. Each housing includes a cavity to retain respective end portions of the drive shaft. An inner side wall of each housing includes a plurality of cylindrical grooves to receive the plurality of ball bearings to transfer torque.

Abstract: The present disclosure provides a test system including a dynamometer to test downhole drilling tools. The system includes a torque load application tool, a thrust load application tool, and a side or radial load application tool to test downhole drilling tool.

Abstract: A drive shaft assembly for a downhole drilling motor includes a drive shaft having a first end portion engaging a first housing and a second end portion engaging a second housing. The first end portion and the first housing form the first constant velocity joint and the second end portion and the second housing form the second constant velocity joint of the drive shaft assembly. Each end portion including a base surface having a pair of prongs extending away from the base surface and a cylindrical side wall having a plurality of ball bearings held in a plurality of circumferentially spaced pockets. Each housing includes a cavity to retain respective end portions of the drive shaft. An inner side wall of each housing includes a plurality of cylindrical grooves to receive the plurality of ball bearings to transfer torque.

Abstract: A drive shaft assembly for a down hole drilling motor is provided. The drive shaft assembly includes a drive shaft having a first end portion engaging a first housing and a second end portion, engaging a second housing. The first end portion and the first housing form the first constant velocity joint and the second end portion and the second housing form the second constant velocity joint of the drive shaft assembly. Each end portion including a base surface having a pair of prongs extending away from the base surface and a cylindrical side wall having a plurality of ball bearings held in a plurality of circumferentially spaced pockets. Each housing includes a cavity to retain respective end portions of the drive shaft. An inner side wall of each housing includes a plurality of cylindrical grooves to receive the plurality of ball bearings to transfer torque.