Caterpillar Inc.

Swetha Suresh

Chetan Vilas Dahiwal

Ebi Bernard

Tamilmurasu Annadurai

Timothy A Thorson

David Jennings Hakes

Thomas J Yaniak

Timothy F Nusz

Scott A Johnston

Akilan Appavu

Brian Stuart Skauge

Gary Clifford Yerby

Geoffrey Damien Chovanec

Benjamin J Bargfrede

Todd M Blindt

Thomas John Yaniak

Roller cone drill bits and methods of increasing the wear resistance of a roller cone drill bit are disclosed. The roller cone drill bit includes a plurality of rolling elements within a bearing assembly of a cone. Each rolling element of the plurality of rolling elements may have a surface hardness of HRC 59-63, a hardened depth that is 0.5 mm to 3.0 mm deep, and may be derived from a low carbon bearing steel material. The hardened depth is measured from the surface of each rolling element and the low carbon bearing steel material has, by weight percent, from 0.12% to 0.25% carbon.

Bearing materials for tricone bit rolling elements

This disclosure describes, in part, systems and structures for a rotary cone drill bit having a body and rolling cone cutters, wherein the rolling cone cutters are coupled to the body through a bearing retention interface including ball bearings in a captured channel between the body and the rolling cone cutters. The ball bearings are inserted through an opening that is subsequently filled with a retainer pin having an engagement feature that ensures alignment of the retainer pin with respect to the captured channel and the ball bearings to reduce wear within the rotary cone drill bit.

Retainer for rotary cone drill bit

A leg assembly of a tricone bit includes a cone and a leg fitting inside the cone. The leg includes an axis defining an axial center of rotation of the cone, a first raceway for a first row of bearings, a second raceway for a second row of bearings, and a third raceway for a third row of bearings disposed between the cone and the leg, at a distal end, at a middle section, and at a proximal end of the leg. A first clearance for the first row of bearings for the first raceway is less than a second clearance for the second row of bearings for the second raceway, which is less than a third clearance for the third row of bearings for the third raceway, such that the first row of bearings initially supports most of the radial load applied to the tricone bit.

Bearing clearance arrangement in a tricone bit

An isolated lubrication system for a drill bit is disclosed. The system comprises a body having a cutting arm with a journal and a rotary cutter mounted on the journal. The system also comprises a reservoir in a body to contain a fluid lubricant that isolated from communication outside the body. The system also comprises multiple conduits in communication with the reservoir and with respect to each other. The multiple conduits facilitate lubrication between the journal and the rotary cutter, including the bearings, by means of a gravitational force and/or a centrifugal force acting of the fluid lubricant. Further, the system comprises a sealing system. The sealing system includes a sealing cap provided to the reservoir, a seal provided between the journal and the rotary cutter, and a stepped passageway provided in a clearance between the rotary cutter and a cutting arm of the body.

Isolated lubrication system for drill bits

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Chennai, India

Swetha Suresh