Casing protection bit
AssigneeMetal Tool Inc.
InventorsTakemi Ishizuka, Seiji Tanaka
Life of this patent
Estimating the term…
Abstract
Provided is a casing protection bit mounted on a casing tube in combination with a cutter bit to prevent abrasion or chipping of the cutter bit. The present invention is to provide a casing protection bit 1 to be mounted on a casing tube, the casing protection bit including: a base portion 2 that protrudes in an axial direction of the casing tube, the base portion having a mountain shape; and two leg portions 3 and 4 extending continuously with the base portion 2 and facing each other at a predetermined distance. In the casing protection bit cemented carbide tips 5a to 5j are disposed on all planes of the base portion 2 except for a plane from which the leg portions 3 and 4 extend.
Claims5
A casing protection bit to be mounted on a casing tube, the casing protection bit comprising:
- a base portion including a front end that protrudes in an axial direction of the casing tube;
- and
- first and second leg portions extending continuously with the base portion and facing each other at a predetermined distance, wherein
- the base portion includes a flat surface part that is continuous to a plane of the first leg portion, a first inclined part that is inclined from the flat surface part toward the front end side in an axial direction of the casing tube, side surface parts each of which is continuous from the flat surface part and the first inclined part, and a second inclined part that is inclined from the first inclined part toward the first and the second leg portions side in the axial direction of the casing tube,
- cemented carbide tips are disposed on the flat surface part, the first inclined part, the side surface parts, and the second inclined part, and
- long-shaped cemented carbide tips are disposed on laterally opposed edges of the first leg portion, the edges extending in the axial direction of the casing tube.
Dependencies are inferred from the claim text.