MINING ROPES.

Otago Witness, Issue 1449, 30 August 1879, Page 8

MINING ROPES.

Truijf fhsrt i« a vtinfor tht silver, Jm& m flat* for iht gold to fine. — Jox, oh. xxvili.

A- very important recommendation has been made to the Mining Department by Mr Nicholas, acting on suggestions of Mr Grainger, the Inspector of Mines, with a view of preventing accidents arising from breakage of ropes. Mr Nicholas points out that the weight of a coil of of hemp rope 1000 feet in length, and 7 inches in circumference, should be 20001b, while iron and steel ropes for equivalent length are in the proportions of 1160 and 7501b respectively. The breaking strain of these is assumed be 14 tons, but the actual load weight on it should not exceed 2 l-10th tons. A flat hemp rope, 4 inches by 1£ inches, weighs 33001b; the brearking strain is estimated at 20 tons, but the actual weight on it should not exceed 2 l-sth tons. He also points out the liability of all ropes to kink, and states that if, after it has done so, it is placed on the drum, breakage is certain to occur after brief usage. He suggests that mining managers should enter into their record-book the conduct of any rope after the first day of usage, and recommends as a test that the rope with the cage attached, weighted one half as much more than when it is ordinarily worked, should be let down to the full depth, then hauled up, and immediately allowed to run down the shaft with the greatest velocity possible consistent with the nature of the skids and appliances used. To prevent kinks when unwinding, the coil should be placed en a turn-table, with an axle runniug through its centre, the speed to be regulated and the rope to be wound on a drum or spider similar in principle to a horse-reel. The Mining Department does not contemplate any mandatory action with reßpscfc to the suggestions, but the publicity given to them, will, it is probable, exert an influence. — Melbourne Age.