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LABOUR-SAVING APPLIANCES IN THE RETORT-HOUSE, AND
IN THE WORKING OF RETORTS.
HERE have been numerous attempts made to solve the
problem of doing away with, or mitigating, the arduous labour of the retort-house, and thanks to the efforts of Mr. John West, of West's Gas Improvement Company, Limited, and others, such attempts have been perfectly successful. Mr. West was one of the first to grapple with the question, and, by patient application, he ultimately surmounted the numerous difficulties which had to be overcome. Mr. Foulis, of Glasgow, was also early in the field, working at the same project, but on different lines, and at the present time the stoking machines of Messrs. West, and of Messrs. Foulis and Arrol, are those generally found in English gas-works. One of the greatest difficulties with early stoking machinery was the question of preparing the coal and conveying it to the charging machine, and it was not until Mr. West had invented and carried out the system of mechanically conveying the coal to machines that any definitely good results were obtained.
When constructing the Manual Charging and Drawing Machines, Mr. West did not attempt to dispense with manual labour to its fullest extent, but to relieve the men of the exposure to heat, and to facilitate the operation of charging and drawing retorts, so that a minimum amount
should be lost while the retort was open during the process of charging.
The result has been that, in addition to these advantages, a considerable saving has been effected on the cost per ton of coal carbonized.
The manual type of Charging and Drawing Machines meets the requirements of small and moderate-sized works, and is successfully employed in gas-works having an annual make of twenty millions, and in works of a much larger make.
The following is a description of West's “Manual” Stoking Machinery, and its appurtenances, comprising coal breakers, coal elevators and conveyers, and coal. hoppers.
The coal breakers are fixed in the coal stores in pits covered by iron framing and floor plates.
The breaker is generally driven by a steam-engine combined with it, or a separate gas-engine can be used for driving the breaker in places where steam is not available. After the coal is broken, it is elevated to hoppers fixed overhead in the retort-house, on girders spanning between the coal store and the retort stack. The elevators consist of malleable iron buckets fitted to a strong detachable link chain. The elevators are driven by belting and chain gear from the coal breaker engines.
In cases where the coal stores are only on one side of a retort-house, containing “through " benches of retorts, the coal is conveyed to the hoppers by horizontal conveyers fixed over the retort bench. The overhead coal-hoppers are fixed conveniently in the retort-house and provided with sliding outlet doors, and levers for supplying coal to the charging machines as they pass under.
The “manual” type of charging machine consists of a square upright frame on wheels, which run on tram rails laid in front of, and parallel to, the retort stack.
The machine is propelled by a hand-wheel and gear fitted to one side of the machine, and on the opposite side, there is a hand-wheel and gear for hoisting and lowering an adjustable coal - hopper from one tier of retorts to another.
The adjustable coal-hopper on the charging machine receives a supply of coal for a number of retorts from the overhead fixed coal-hoppers in the retort-house, and is free to move up or down between the four uprights of the charging machine frame, being guided by them, and suspended by chains leading over pulleys carried by the top cross members of the frame. A light frame is suspended from the coal-hopper for carrying the charger when it is out of the retort. At the bottom of the hopper, but directly over the charger, is a feeder-box, controlled by a hand-wheel when supplying the charger with coal.
The West" manual charger consists of a light carriage, running on three wheels and having two semicircular scoops at the bottom. These scoops are arranged to turn over in opposite directions by the twisting of the long driving-rod about half way round in one direction, and, when turned over, all the coal contained in the charger is free to fall out on to the floor of the retort.
The method of working the charging machine is very simple, and is as follows:
The machine receives a supply of coal from the overhead hopper, and is propelled to the retort which is to be charged. Arriving opposite the retort, a drawbridge, hinged to the frame carrying the charger, is allowed to fall until it rests on the front of the floor of the mouthpiece. The stoker then gives the hand-wheel controlling the feeder-box a few turns, whereby the coal is allowed to flow from the hopper until the charger is full. The charger is then pushed intothe retort by means of the long rod, and on arrival at the end of a single retort, or just past the middle of a
through,” the handle and rod are turned so as to reverse the scoops forming the bottom of the charger, and the coal falls out. The charger is drawn back into the machine, is filled as before, then it is pushed into the same retort to a previously arranged distance, the scoops turned over, and the charger withdrawn. The retort will then be charged with an even layer of coal, slightly deeper at the sides, and so perfect, that no skilled stoker can equal it either by the use of the scoop or shovel.
After charging a retort, the machine is propelled to the next retort in the same tier, and so on, until the stipulated number of retorts are charged.
The manual type of drawing machines is a frame on three wheels, carrying an adjustable arm, supporting the rake rod with its head. Hoisting gear is fixed to the frame, to adjust the rake rod and head to the several tiers of retorts. The machine is constructed so as to enable a coke barrow to be placed under the mouthpiece, and the coke can then be drawn direct into the barrow.
A removable platform is used for drawing the top tier of retorts. By means of this machine the stoker is enabled to use a large, wide rake head, as the effort to lift its weight is taken by the machine.
For large works Mr. West employs power-driven stoking machinery, the power being either compressed air or machine-driven cotton or wire ropes.
In the“ West” charging machine the action of the scoop in charging by hand is reproduced.
The scoop, which is the full length of the retort, enters twice, emptying itself alternately left and right. It is constructed with a thin blade running down its centre, the object of this being to throw over and distribute the coal evenly on the floor of the retort when the
scoop is turned. The scoop holds two hundredweight of coal. The carrier to which the scoop is attached runs in horizontal guides on the framing of the machine. Each extremity of this carrier has a chain affixed thereto which is wound round a drum. By means of a rack and pinion this drum is rotated in either