IMPROVED OFFTAKE-SOCKET FOR COUPLING AND UNCOUPLING HAULING-ROPES.

BY W. C. BLACKETT.

The improved socketing contrivance for haulage purposes, which the writer had lately devised, was intended mostly for use underground. It was principally intended as an improvement upon the appliances now in use for the quick coupling and uncoupling of ropes at way-ends, but other uses would doubtless suggest themselves to the members.

Fig. 1 illustrates both the old arrangement (AB and CDE) and a variety of the new contrivance (F, G, H, I and J). In the old arrangement, A is the socket, similar in many respects to that

already described by the writer,* in which the rope is held by means of a tapered copper plug; B and C are the offtake-key and slotted lock or box, used for ready detachment; D is a swivel for avoiding any "spin" that there may be in the rope; and E is the socket at the other end.

Instead of this somewhat lengthy arrangement of links, the new device substitutes two sockets, both of which may be like F, with a connecting-piece, G, joined as shewn at J; or the connecting piece, G, instead of being rigid, may be linked. But it is, perhaps, preferable that an ordinary socket, H, should be attached to a socket, I, which again may be either rigidly joined or preferably have an interposed link.

* Trans. Inst. M.E., 1901, vol. xxiii., page 10.

THE NORTH OF ENGLAND INSTITUTE OF MINING AND MECHANICAL ENGINEERS.

EXCURSION MEETING OF ASSOCIATES AND STUDENTS,
HELD AT NEWBOTTLE COLLIERIES, SEPTEMBER 3RD, 1902.

NEW BOTTLE COLLIERIES.

MARGARET PIT.

The Margaret pit is one of a group of nine pits comprising the Newbottle collieries, belonging to the Lambton Collieries, Limited. It is situated in the parish of Newbottle, about 1 miles southeast of Penshaw station.

There are two pits, both of which are downcasts, one being 12 feet and the other 8 feet in diameter. This latter pit was sunk in 1774, and has been drawing coals continuously since that date.

The ventilation is produced by a Waddle fan situated at a ventilating-pit, 1,500 feet from the colliery, and producing 160,000 cubic feet of air, with a water-gauge of 13 inches at 54 revolutions per minute.

Four seams are being worked at this colliery, namely:

The system of working in the Brass Thill seam is longwall, and in the other seams, bord-and-wall.

per day.

The output is 800 tons

There are 7 Lancashire boilers at this pit, each 8 feet in diameter, 30 feet long, and working at a pressure of S0 pounds per square inch. The boilers are fitted with Proctor mechanical

stokers.

Electrically-driven Coal-cutters.-The generating-plant, which was not specially erected for driving the coal-cutting machines,

has been in existence for several years for hauling, pumping and winding. It was installed in 1891, and except for the renewals of certain parts, it remains exactly to-day as it was at that time. The engines for driving the generating dynamos are of the Willans high-speed type, two in number, each being equal to 140 indicated horsepower, at a speed of 380 revolutions per minute. The steampressure is 80 pounds per square inch. Each engine has two cylinders, 17 inches in diameter, with a stroke of 8 inches. There are two generating dynamos, driven by means of link-leather belts, 18 inches wide, and each capable of giving out 80 ampères at a pressure of 780 volts, when running at a speed of 500 revolutions per minute: this is equal to an output of 84 horsepower.

The coal-cutters are of the diamond type of disc coal-cutter. Each cutter is driven by two series-wound motors at a pressure of 500 volts. The revolutions of the cutter-wheel are about 12 per minute. The diameter of the cutter-wheel, with cutters and boxes fixed, is 6 feet 4 inches. The average depth of the cut is usually a little over 5 feet, and the height of the cut is 4 inches. The power required to work each coal-cutter is on an average about 15 horsepower. Each machine is controlled by a reversing-switch fitted with resistances. The machine is drawn along the face, and kept up to its work by a rope-hauling arrangement, fixed to the end of the machine and worked by ratchet-gear from the driving-shaft.

The Brass Thill seam, in which the coal-cutting machines are working, has not previously been worked at these collieries, owing to the bands of stone which it contains. An average section of the seam is as follows: ·

Its inclination is about 1 in 36, dipping eastward. It is overlain by a roof of mild blue metal, and it has a hard fire-clay floor. The seam is entirely free from water, and fire-damp has not been found.

The coal-cutter kirves in the upper band, that is, above the level of the machine.