Abstract: A roller cutter intended to be used at a drill head for rotary boring of the front of earth and rock formations, the roller cutter having a centre line and being provided with a hub having rows of crushing members. At least one crushing member has its longitudinal axis at an angle relative to a normal to the centre line. The hub is rotatable in relation to a shaft having shaft spigots. The roller cutter is provided with at least one seal retainer arranged at an axial end of the hub in order to hold a sealing means in position. The hub includes at least one circumferential recess positioned axially inward relative to a radially inward projecting flange in the hub.

Abstract: A roller cutter includes a hub having crushing members mounted on an outer periphery thereof, and a shaft on which the hub is mounted for rotation. Opposite ends of the shaft include respective spigots. Seals are disposed adjacent respective ends of the shaft and are arranged radially between the shaft and the hub for preventing leakage of lubricant. Covers are disposed axially outwardly of respective seals for covering the respective seals. Each cover includes a generally radially inwardly directed projection received in an indentation formed in an outer surface of the shaft to lock the cover axially and rotationally with respect to the shaft.

Abstract: A raise boring head includes a roller cutter body and a saddle intended for rotary drilling in earth and rock formations. The roller cutter body is rotatably journalled on a shaft that is provided with two shaft spigots at its opposite ends. Each spigot has a second support surface provided for cooperation with a first support surface of the saddle to hold the roller cutter to the saddle. Each shaft spigot is provided with a hole for receiving a fastener that also passes through the second support surface in order to connect the shaft spigot to the saddle. The first support surface and the second support surface are curved. The first support surface and the second support surface connect directly or indirectly to stop shoulders for counteracting rotation of the shaft. The fastener is eccentric to the shaft axis and arranged to press the stop surfaces together.

Abstract: A raise boring head includes a roller cutter body and a saddle intended for rotary drilling in earth and rock formations. The roller cutter body is rotatably journalled on a shaft that is provided with two shaft spigots at its opposite ends. Each spigot has a second support surface provided for cooperation with a first support surface of the saddle to hold the roller cutter to the saddle. Each shaft spigot is provided with a hole for receiving a fastener that also passes through the second support surface in order to connect the shaft spigot to the saddle. The first support surface and the second support surface are curved. The first support surface and the second support surface connect directly or indirectly to stop shoulders for counteracting rotation of the shaft. The fastener is eccentric to the shaft axis and arranged to press the stop surfaces together.