Integrated bearing section and method

A method of absorbing a radial load and a thrust load in a mud lubricated drilling motor, comprising the steps of:

• a) providing an integrated bearing section for the drilling motor comprising:
• a housing with a housing inner bore;
• a mandrel at least partially disposed within the housing inner bore, the mandrel being a generally cylindrical unitary member having an inner bore for the transmission of a drilling mud and an expanded diameter lower end, the mandrel including an outer surface having a series of circumferential grooves;
• a plurality of spherical members, wherein each of the spherical members is disposed partially within one of the circumferential grooves of the mandrel;
• an outer radial bearing disposed around the mandrel and within the housing inner bore, the outer radial bearing including an even inner surface, wherein at least one of the spherical members engages the even inner surface of the outer radial bearing for allowing relative axial movement between the mandrel and the outer radial bearing;
• and an outer thrust bearing disposed around the mandrel and within the housing inner bore, the outer thrust bearing including an inner surface having a circumferential groove, wherein at least one of the spherical members engages the circumferential groove of the outer thrust bearing;
• and wherein the outer radial bearing and outer thrust bearing are in direct contact with each other;
• b) transmitting torque to the mandrel to rotate the mandrel relative to the housing, the outer radial bearing, and the outer thrust bearing;
• c) absorbing a radial load with the outer radial bearing and absorbing a thrust load with the outer thrust bearing;
• and
• d) allowing relative axial movement between the outer radial bearing and the mandrel as the spherical members or the circumferential grooves wear.