Boring drill bit

Patent · Tue Dec 02 04:00:00 EST 1986

OSTI ID:7041387

Takano, S

This patent describes a boring drill bit which comprises a shank which has a first end that can be attached to a drill pipe and second end, the shank defined an axial line therethrough and an elongated pin connected to the second end of the shank and around its circumference. The elongated pins extend radially outwardly with respect to the axial line and away from the first end of the shank so as to be inclined with respect to the axial line. Each elongated pin has a root end connected to the shank and a free end and each elongated pin having a side surface and an end surface. The drill bit also comprises roller cutters, each roller cutter having a generally cylindrical bore therein to enable it to be rotatably positioned over a respective elongated pin; The improvement described here is wherein the side surface of each of the elongated pins has an undulating shape such that successive cross sections through the elongated pin between the free end and the root end will be circular and will have gradually decreasing and then gradually increasing diameters. A generally cup-shaped plain bearing is positioned between each elongated pin and each associated roller cutter, each generally cup-shaped plain bearing member having a side wall composed of separate portions and a bottom portion which covers the end surface of the elongated pin. The side wall has an inner surface which is shaped to correspond with the undulating shape of the side surface of the elongated pin.

• Assignee: Sumitomo Metal Mining Co., Ltd., Tokyo
• Patent Number(s): US 4625816
• OSTI ID: 7041387
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
42 ENGINEERING
420206 -- Engineering-- Mining & Drilling Equipment & Facilities-- (1980-1989)
BEARINGS
DESIGN
DRILL BITS
DRILLING
DRILLING EQUIPMENT
EQUIPMENT
INCLINATION
MOTION
NATURAL GAS WELLS
OIL WELLS
POSITIONING
ROTATION
WELL DRILLING
WELLS