664 PROCEEDINGS OF SECTION H. 



4.— SOME NOTES OX TESTING WIRE ROPES. 

 By ROBERT HUNTER. 



In the middle of the year 1907 there was pubhshed at Pretoria 

 the report of a commission appointed by His Excellency the Lieu- 

 tenant-Governor of the Transvaal to inquire into and report upon the 

 use of winding ropes, safety catches, and appliances in mine shafts. 

 This report has, since its publication, been widely circulated and 

 discussed among mining men, as it contains much valuable informa- 

 tion. The majority of the witnesses examined by the commission 

 with reference to winding ropes appear to have been interested in 

 their manufacture and sale, the published evidence with regard to 

 deterioration in ropes in actual use being extremely limited. This., 

 perhaps, is not astonishing, when it is remembered that most of 

 those competent to furnish information on this point are very busy 

 men, who could ill spare the time necessary to enable them to place 

 their knowledge before the commission in an acceptable form. The 

 writer annu.ally tests from 160 to 200 ropes, and it has occurred to 

 bim that others may be interested in the results obtained when 

 testing ropes in use. 



Most of the ropes used in Queensland mines are of simple con- 

 struction, that is to say, of six strands, each containing seven wires, 

 of Lang's lay, having an ultimate stress of from 17 to ^^5 tons. 

 Frequently one wire in each strand is merely a core wire, being made 

 of low grade steel or of iron. Unless the core wire is equal to the 

 other wires in the strand, it is not considered in calculating the 

 ultimate stress of the rope. A few compouttd ropes are in use having 

 an ultimate stress of from 45 to 60 tons. Manufacturers have 

 adopted a classification of ropes presumably based on the composition 

 of the steel, but this classification, judging by the results of tests, 

 does not always present the uniformity that is desirable. In its 

 report, the Transvaal Commission states " that the deterioration of a 

 winding rope should be capable of being assessed by a competent 

 person while making the customary examination is a most essential 

 point." 



In Queensland sets of rope-testing machines have been placed in 

 centres most convenient to the inspectors of mines. With these 

 machines wires are subjected to bending, torsion, and tension tests. 

 The two first-named tests, of course, have reference to the temper of 

 the steel. It may not, perhaps, be out of place to hei-e describe the 

 system of rope-testing adopted by the Department of Mines in this 

 State. When a new rope is purchased, a piece is cut off by the 

 purchaser, and sent by him to the inspector of mines, together with 

 a copy of the manufacturer's certificate. That oflBcer then tests it, 

 . and enters the results in a register kept for the purpose, and also 

 furnishes the purchaser with a copy of the entry in the register. 

 Aftei^-arcfs, whenever the rope is reshod, a similar test is made, the 

 wires at the same time being carefully examined for signs of deterio- 

 ration. The wires are tested singly, and in calculating the ultimate 

 strength of the rope a deduction of 10 per cent, is generally made 

 from the aggregate of the wires, experience having shown that when 

 the result obtained by this method of testing is compared with the 

 result obtained by testing a whole piece of rope this is a fair average 

 deduction. In comparing tests of new ropes Avith the manufacturers' 



