The Mechanical Handling and Storing of Material

94 THE MECHANICAL HANDLING OF MATERIAL which are more trying than in this country. The general arrangement, with the few exceptions men- tioned in the preceding remarks, of this steel band conveyor is similar to that of the ordinary belt conveyor. This may be seen from Figs. 118 and 119, the former being a single band 16 in. wide. The latter is a com- pound band composed of three widths ; two bands run side by side leaving a space of about 4 in. between, and this space is covered by a .third band running over the gap, and overlapping the two side bands by about 4 in. The centre band is put on with a little less tension than the other two, in order to secure an easy fitting of the bands, and as the greater part of the load is always carried in the centre, its weight will tend to keep the middle band tightly against the others. The band is joined transversely by a row of rivets, the holes being countersunk. About 16 ft. from the head end of the return strand is a kind of steering gear, which keeps the band in its pro- per position. This will be de- scribed later. The Terminal Drums.— These, as already mentioned, should not be less than 40 in. in diameter. They are also narrower than the band, con- trary to the practice in textile belts, and this is to prevent any particles being caught between the bands and the drums. The terminals are generally ordinary pulleys, wood lagged, and covered with a rubber coating, similar to that used for ordinary rubber- covered conveyor bands. As it is very important that no hard