Two part mine roof support unit

摘要

A mine roof support unit is constituted by two detachably connected parts. Each of the parts has a floor girder which supports a roof bar by means of a hydraulic prop. The roof support unit is intended for use at the lower end of an inclined longwall working which meets its access gallery at an angle other than 90 DEG . The detachability of the two parts enables one of these parts to be removed from the working as its face is advanced. The removed part can then be transported to the other end of the working. Each of the parts is provided with means for detachably connecting an advance mechanism.