Sandvik Ab

Sandvik Intellectual Property Ab

Michael Andrew McLean

Steven Lee Weaver

Mark James Truebody

Eric Ivan Johnson

A drill bit for attachment to an elongate drill rod, the drill bit including means for attachment to an end of the drill rod, and a leading end which defines a pair of diametrically opposed slots which open axially for receipt of a portion of a drill tip which projects axially from the slots. The drill tip being fixedly secured within each of the slots. Further, a drill rod or a self drilling roof bolt comprising the drill bit.

Drill bit, a drill rod and a self drilling roof bolt

An end protector for a working element of a road grading machine or the like. The working element includes a body portion having a plurality of holes therein for holding picks that work a road surface. The end protector is held in place through the use of a vacant pick hole of the working element by a fastening element that extends through the hole.

Surface working device and attachable protector

An elongate roof bolt includes a bolt body having an axially extending central bore and defining a leading end. The leading end includes a pair of axially extending abutment elements formed by machining. Each abutment element includes an abutment face for engagement with a drill tip on opposite sides thereof, to transmit rotary forces during drilling. The drill tip extends across the leading end of the bolt body and is bonded to the abutment elements by welding, soldering or brazing. The bore opens out of said bolt bonded adjacent said leading end.

Self drilling roof bolt

An extension drilling system for use with a semiautomatic drilling rig. The drilling system includes a plurality of extension rods constituting a drill rod string and having cooperating male and female threaded couplings therebetween, and being right-hand rope threaded couplings. A reversible drive chuck of a drilling rig drives (either directly, or via an adaptor), the outside of the female threaded end of an associated extension rod. A gripper grips one of the extension rods to hold the drill rod string stationary when the chuck is driven in reverse. The gripper is located such that only one threaded coupling is disposed between the chuck and grippers and to ensure that when the chuck is rotated in reverse, only the desired coupling is uncoupled. The drill rods have axial passages therethrough in communication with each other and through which flushing fluid is delivered to an associated drill bit and a non-return valve is incorporated in the passage through at least one of the drill rods. A socket of the drive chuck (or adaptor) is configured to automatically lock the drill rod in the socket in response to rotation of the drive chuck.

Growing community of inventors

Hamilton East, Australia

Michael Andrew McLean