Rock drill bit, a drilling assembly and a method for percussive rock drilling

摘要

A rock drill bit for percussive drilling comprising a bit head configured to be attached at an end of a drill element of a drilling assembly and having a diameter larger than that of a said drill element. The bit head has at a front end as seen in the intended drilling direction a generally frusto-conical shape defined by a substantially circumferential ring provided with a plurality of gauge buttons distributed along the extension of the ring for engaging material to be crushed. A central flush channel extends through the bit head and has at least one flushing hole opening at said front end to conduct flushing medium to said front end. At least one peripheral flushing hole of said at least one flushing hole opening at said front end opens in said substantially circumferential ring. At least two peripheral flushing holes open in said substantially circumferential ring.

主权项

1. A rock drill bit for percussive drilling comprising:
a bit head configured to be attached at an end of a drill element of a drilling assembly and having a diameter larger than that of a said drill element, wherein said bit head has, at a front end relative to an intended drilling direction, a generally frusto-conical shape defined by a substantially circumferential ring, wherein said bit head includes:
a plurality of gauge buttons distributed along an extension of the ring, anda central flush channel extending through the bit head and having at least three flushing holes that each open at said front end to conduct flushing medium to said front end, and wherein one of the at least three flushing holes is a face flushing hole that opens at a front surface of the bit head and two of the at least three flushing holes are peripheral flushing holes that open in said substantially circumferential ring, and wherein said bit head has a circumferential surface and further includes a plurality of recesses in the circumferential surface through which flushing media is conducted rearwardly, externally of the rock drill bit.