REPORT ON PUMPING PLANT FOR KIMBERLEY MINE
plant consists of a vertical triple-expansion condensing engine, having
cylinders 15-1/2 in., 23-1/4 in., and 37 in. diameter respectively,
with a stroke of 36 in.
high and intermediate pressure cylinders are arranged tandem, over one
crank, the low pressure working on the other, which is placed at the
opposite end of the crank-shaft and at an angle of go° with the other.
double acting air pump is driven by a rocking lever from one cross-head
and a feed pump in the same manner from the other engine.
cast steel spur-wheel, 3 ft. 9 in. pitch diameter, is keyed on the
engine shaft, and drives a second shaft 27 in. diameter by gearing with
a spur-wheel 30 ft. pitch diameter made of cast iron, with teeth 6 in.
pitch by 30 in. face. The gears were made by Fraser & Chalmers, of
Chicago, U.S.A., the crank-shafts by Sir J. Whitworth, of Manchester,
and the rest of the work, including the pumps, by Messrs. J. Simpson
& Co. Ltd., of London. A cast-steel crank is keyed on the second
motion shaft, and drives the T bob by a pitman with 35 ft. centres.
the nose of the bob is hung the spear rod 1250 ft. long, of hard pine,
14 in. square for the first 500 ft., 12 in. square for the second, and
10 in. square for the remainder.
total weight of the rod, including strapping plates and poles, is 61
tons, which will be partially balanced by a counterweight on the top
bob, and partly by a second bob placed at the 1200-ft. level.
to the spear rod at the 250 ft., the 500 ft., the 750 ft., the 1000
ft., and the 1200 ft. levels are cast-iron plungers 14 in. diameter,
having a stroke of 10 ft., each of which forces the water to the next
station above through a riveted steel pipe, 14 in. diameter, with
joints riveted together.
The foundations for the driving machinery are made of concrete, with the proportion of cement to stone of 1 : 9 on the average.
L. I. SEYMOUR, Mechanical Engineer. 318