Denaby Main Colliery – Description of Workings

February 1892

Mexborough & Swinton Times – Friday 12 February 1892

The Yorkshire Coalfield

Denaby Main Colliery

This colliery is situated near Mexborough, and is owned by the Denaby Main Colliery Company, Ltd, Mr J Buckingham Pope chairman of the company.

The company was established in 1867. The mineral property under lease stretches continuously from Swinton to Doncaster, a distance of 7 miles and in about 7,000 acres in area.

The working of the Barnsley seam at Denaby Main Colliery is most extensive: besides this, a new winning to the same seam is in progress at Cadeby, which, with the plant in course of erection, promises to be a colliery on a more extensive scale.

The principal mineral owners in the above named area of the Earl of Mexborough, Lady Watson – Copley, John Fullerton, Esq., Andrew Montagu Esq., and the executors of the late George Dawes.

There are two shafts at Denaby Main, about 40 yards apart; the winding and down cast shaft is 14 foot in diameter, the upcast is 13 ½  feet in diameter; both are lined with cast-iron tubbing from the surface to a depth of 70 yards, below that with 9 inch bricking to the Barnsley seam, depth 448 yards from the surface. The Shafton seam was passed through at the depth of 11 yards, below this the strata were compound for the most part of fissured sandstone, which gave off water largely, necessitating the insertion of tubbing.

The winding engine at the down cast shaft as to 40 inch horizontal cylinders, 6 feet stroke, 18 foot plane drum unbalanced; it raises six tubs at once in each cage, on three decks, weight carried in each 10 cwt; including changing tubs each lift is made in one minute. The output of coal is 2000 tons per day or 14 hours work. The drawing ropes are of plough steel, 5 inch in circumference, the breaking strain of which is 120 tons. The conductors are of pitch pine, two to each cage. The tubs, at the top and bottom, are landed in three separate platforms, corresponding to the three decks, simultaneously; the two lower platforms at the surface are afterwards raised by hydraulic power to the platform, which is on a level with the tipplers of the screens. The headgear of wrought iron stands 64 feet from the surface; height of the landing stage 16 feet; leaving height up to the pulleys 48 feet.

The winding engine at the utmost shaft has two 20 inch horizontal cylinders, 5 ft stroke; this is used as an auxiliary for changing the work men during the 14 hours work. Both winding engines were built by the Worsley Mesnes Ironworks Company of Wigan.

No pumping engine at the surface is necessary, as what little water that runs to the sump is raised occasionally by the auxiliary engine. An hydraulic pump is placed in the cast engine plane of the Barnsley seam, which dips one in 10, at a point about 1000 yards from the bottom of the shaft; this pump has a ram 2 inches diameter. The vertical rise to the shaft will be hundred yards; this gives a head of water from the surface of 1644 feet or 718 pounds hydraulic pressure per square inch at the pump; a small quantity of water at this pressure in the pumps officiant suffices to force a much larger quantity up the shaft.

The mine is ventilated by a Leeds fan, 40 foot in diameter, 12 foot wide. This fan differs from the Gufbal in that it has two inlets for air, one at each side, and a vertical diaphragm in the middle for keeping separate the entering currents. The fan is driven by a 30 inch horizontal engine, 3 ft 4 in stroke and is duplicated. 48 revolutions are made by the engine and fan per minute, giving a circulation of air in the mine of over 178,000 ft³ per minute.

15 Lancashire boilers supply steam to the engines on the surface, and to the hauling engines based on the ground; these boilers are fed by means of Bennis mechanical stokers, the chief advantages of which are said to be small prevented, saving on labour and fuel, and the use of very small coal, such as passed through 5/16 inch holes.

Steam pressure 70 lbs at the boilers