Safety Volume 6-8 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1918 Excerpt: ...lower the load so that it might be rolled into its final position. Everything had progressed up to this point as previously arranged and the division of the load between the two cranes was safe because the angle of elevation of the boom and of the cables from the two booms to the sling about the load was right. While lowering, however, a circumstance not yet A Crane Accident Due to Overloading the Boom Beyond Its Safe Capacity The damaged crane had been used in conjunction with the other crane shown in the illustration to raise the load from a flat car. In lowering the load, one of the cranes ran out its cable more rapidly than the other, causing the overload which resulted in the accident. Fortunately, there were no casualties although the load was seriously damaged. determined, took place by which one of the cranes let out its cable more rapidly than the other. This may have been due to a misunderstanding of signals given by the ground man to the crane operators, to brakes that held less readily on one crane than on the other; or possibly to the fact that the proportion of the load to be carried properly between them (the cranes were not of the same capacity or dimensions), and the rate at which the cable on one crane drum should have been paid out with relation to that on the other, had not been determined. As a result, the larger crane suddenly received a load greater than its safe capacity at the particular angle of elevation of its boom at the time. The boom crumpled very near the middle and the load was dropped with serious damage to itself. Fortunately, nobody was injured, although three men on the ground narrowly escaped death or serious injury. In this case it is obvious that the cranes were called upon to operate under conditions which could not ...