A cutting device for engaging a rock face includes a disc body supported for rotation about an axis of rotation, and a plurality of peripheral portions removably secured to the disc body. Each of the peripheral portions including a plurality of cutting bits positioned on a peripheral edge. The peripheral edge of each peripheral portion is aligned with the peripheral edges of adjacent peripheral portions.

A cutting device for cutting rock includes a disc and a plurality of cutting elements secured to the disc. The disc is supported for rotation about an axis of rotation, and the disc includes a peripheral edge extending around the axis of rotation. The plurality of cutting elements are spaced apart along the peripheral edge of the disc and positioned in a cutting plane. Each of the cutting elements includes a base portion and a cutting portion including a cutting edge, and the cutting portion has a width that is larger than a width of the base portion.

A rotary cutting head for a cutting machine having a plurality of nozzles positioned at a peripheral portion of the head to direct a fluid jet to a selection of cutting buttons located at cutter discs. The nozzles are positionally mounted at the head so as to direct the fluid jets to a radially outermost selection of the buttons during cutting.

A cutting device for cutting rock includes a disc and a plurality of cutting elements secured to the disc. The disc is supported for rotation about an axis of rotation, and the disc includes a peripheral edge extending around the axis of rotation. The plurality of cutting elements are spaced apart along the peripheral edge of the disc and positioned in a cutting plane. Each of the cutting elements includes a base portion and a cutting portion including a cutting edge, and the cutting portion has a width that is larger than a width of the base portion.

A cutting device for engaging a rock face includes a disc body supported for rotation about an axis of rotation, and a plurality of peripheral portions removably secured to the disc body. Each of the peripheral portions including a plurality of cutting bits positioned on a peripheral edge. The peripheral edge of each peripheral portion is aligned with the peripheral edges of adjacent peripheral portions.

A cutting apparatus suitable for creating tunnels and subterranean roadways includes independently pivoting supports that each carry a respective independently pivoting arm and a rotatable cutting head. Each cutting head via the supports and arms, is configured to slew laterally outward in a sideways direction and to pivot in a vertical upward and downward direction. The supports and arms are mounted on a linear moving sled carried by a main frame.

A cutting apparatus includes a support structure and first and second cutting assemblies. Each cutting assembly includes a rotatable cutting head and a mounting assembly for movably attaching the cutting head to the support structure. The cutting head is movable about a first pivot axis of the mounting assembly in a sideways direction relative to the support structure, and about a second pivot axis in an upwards-downwards direction. Each cutting head includes a plurality of cutting units, which each have a rotatable shaft and a cutter mounted thereon. The cutter includes a disc body and a plurality of buttons mounted in a radially peripheral portion of the disc body. At least some of the buttons have a central longitudinal axis that subtends an angle to a reference axis, which extends perpendicularly outwards from an axis of the shaft, the angle being to 20 and to 34.

A cutting device for engaging a rock face includes a disc body supported for rotation about an axis of rotation, and a plurality of peripheral portions removably secured to the disc body. Each of the peripheral portions including a plurality of cutting bits positioned on a peripheral edge. The peripheral edge of each peripheral portion is aligned with the peripheral edges of adjacent peripheral portions.

A device for the installation of rock bolts includes a supporting structure and first and second bolting units mounted to the supporting structure. Each bolting unit is configured for drilling an installation hole and/or for installing a rock bolt into a rock face, wherein the supporting structure is configured for rotatably moving the first and second bolting units about a common axis of rotation. At least one actuator is mounted to the supporting structure and configured for additionally moving at least one of the first and second bolting units.

There is provided an excavation assembly for use in an excavator, wherein the excavation assembly is removably coupled to an arm at a pair of spaced shaft-receiving portions defined therein, wherein the excavation assembly performs an excavation operation into a ground or a rock, wherein the excavation assembly comprises: a body removably coupled at one end thereof to the pair of spaced shaft-receiving portions; a driving mechanism configured to generate at least one of a linear driving force, a rotational driving force, and a striking force; an excavation tool coupled to the driving mechanism and configured to be driven by at least one of the linear driving force, the rotational driving force, and the striking force transmitted from the driving mechanism, thereby to perform the excavating operation, wherein a direction of the excavation operation by the excavation tool varies depending on coupling positions between the pair of spaced shaft-receiving portions and the body.