Abstract: The mine roof anchor includes a roof bolt assembly with an expansion shell assembly secured at the end of the bolt inserted into the bore hole. The expansion shell assembly includes a friction reducing means to increase the horizontal force on the leaves and the bolt assembly includes an adjustable resin retaining washer to compress the resin in the bore hole.

Abstract: A self-propelled continuous mining machine includes a mobile frame assembly having a front end portion with a boom assembly pivotally retained thereon. A dust collecting system is positioned on the mobile frame assembly for inducing a flow of air through a hollow interior portion of the boom assembly. As a dislodging head removes material from a mine face, the dust collecting system draws airborne dust created by the dislodging head through a hollow interior of the boom assembly and into the collecting system mounted on the mobile frame assembly. Two portions of the boom assembly are pivotally connected to portions of the collecting system mounted on the mobile frame assembly to provide pivoting joints to allow the collecting system to draw airborne dust through the boom assembly with the boom assembly in any preselected position relative to the mobile frame assembly.

Abstract: A material handling platform is pivotally attached to the front of the material transport vehicle. Actuator means raise and lower the platform. The platform is arranged to tilt relative to the vehicle about a horizontal pivot at the front of the vehicle. A turntable is mounted on the platform. The material handling platform positions roof supports in an underground mine adjacent a long wall mining machine. The roof supports are transported by the material transport vehicle carrying the material handling platform with the longest dimension of the roof support aligned with the longitudinal axis of the vehicle. After the roof support reaches the position where it is to be installed, the roof support is turned relative to the vehicle by turning the turntable of the material handling platform so that the longest dimension of the roof support is at right angles to the longitudinal axis of the vehicle. The roof support is then removed from the vehicle by lowering and tilting the platform relative to the vehicle.

Abstract: A mechanical expansion shell assembly has an expansion shell with a plurality of leaves and a plug with a plurality of sloped surfaces. The inner surfaces of the leaves are positioned in overlying relation with the sloped surfaces of the plug. A friction reducing material is positioned between the overlying surfaces and is arranged to reduce the torque applied to the roof bolt connected to the expansion shell assembly to obtain a preselected lateral force on the expansion shell leaves. In another embodiment, a friction reducing material is positioned between a nut threaded on the roof bolt and the underside of the expansion shell ring portion.