Non-rotating stabilizer for earth boring and bearing therefor

Abstract

A stabilizer for a big hole drill stem includes a journal, i.e., a sleeve, adapted to be slipped over the stem. The sleeve has an apertured lower flange to seat on the stem stool and receive the pins thereof to prevent relative rotation of sleeve and stem. The upper end of the sleeve has a clutch jaw for interlocking with the clutch jaw on the lower end of a canister weight forming part of a drill string assembly. Also, the upper end of the sleeve, just below the clutch, has a split clamp held in frictional engagement with the sleeve in an annular groove thereabout. Just below the clamp there is an annular upper flange having stop lugs engageable between the ears of the clamp to prevent relative rotation. Rotatably mounted on the sleeve between the upper and lower flanges is a fixed blade stabilizer body. A marine bearing is provided at the inner periphery of the stabilizer to take radial loads. The marine bearing is fabricated from a plurality of fluted rubber rings cemented to each other and to the steel part of the body. Between each end of the body and the flanges is a thrust bearing. Each thrust bearing is a sandwich comprising two thrust plates, one screwed to the body and one screwed to the adjacent flange, with a support plate studded with thrust buttons floating therebetween. The buttons have heads and extend through holes in the retainer plate with the heads alternately on opposite side of the retainer plate. Preferably the thrust buttons are made of a long wearing, hard, high strength plastic, compatible with salt water, drilling mud, sand, and rock cuttings, a suitable plastic being one sold under the tradename "Ultra-Cladd" or "Ultra-Wear", same being an ultra high molecular weight polyethylene.

Dependencies are inferred from the claim text.