The Mechanical Handling and Storing of Material

COAL FACE CONVEYORS l6l tipping up by gravity, and assuming its former position as soon as empty. Walton & Kayner employ a textile band which rests with its upper strand in the bottom of the segments, which are set in motion when the train is in the unloading position at the gateway. Cummings & Gardiner, as well as Gibb, use a steel band employed in a similar manner. . Thomson's conveyor (Fig. 215), which is essentially a trough open on one side, is emptied by an oblique scraper as it passes over the bridge at the gate. As regards capacity the Mickley conveyor at the Prudhoe Pit of the Mickley Coal ompany is handling 5 tons per hour. The installation of the Cummings & Gardiner conveyor at Hampstead Colliery has increased the output from 27 tons to 4-5 tons per man per shift. The Bothwell conveyor of the Bothwell Park Colliery has increased the lig. 215. The Thomson Coal Face Conveyor. View from Coal Face. output from 2 tons to 6-5 tons per man per shift. The Gibb conveyor at the Muiravon- side Colliery has a capacity of 13 tons per hour. Class B.—Appliances in which the coal is carried on an endless movable band As band conveyors are fully dealt with in Chapter VII, it will only be necessary to mention any peculiarities for this particular use of a well-known type of conveyor (introduced by Richard Sutcliffe, of Wakefield). For the band itself hemp or flax is most serviceable. Jute cotton and the bass of the ancient lime tree are also used, but they do not last as ong, and occasionally woven wire bands are employed. All textile bands softer much iom the damp atmosphere in the mines, and to avoid this they are impregnated with various substances such as balata ; tar being also used for this purpose. I he width of the band generally varies between 20 and 24 in. The idlers with their frames are kept as low as possible, so that the conveyor may be applicable in small seams, eie troughing idlers are used they are, for the same reason, in a more shallow position 11