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If an electric motor is used to drive the line shaft it will be convenient to place it overhead and near the center of the shaft, on a platform erected for the purpose, rather than to place it on the floor level, where it will be subjected to dirt and accidental injury.
A jib crane may be erected to serve the large steam hammer and an overhead trolley for the smaller one, the latter being the more economical of the two, and will be found nearly as convenient for comparatively light weights. The I-beams carrying the trolley and hoist should run from a point nearly over the center of the forge to a point close to the left side of the hammer, as seen on the plan.
Pneumatic hoists may be conveniently used not only on this trolley but in a similar way at the forge lathe and over some of the other machines for handling heavy bars. They work quickly, are easily handled, and when necessary may be readily moved from place to place.
The space for bar stock is located conveniently to the railroad track and the tram car track, and contains two racks for bar stock, the larger one for full length bars of iron and machine steel, and the smaller one for ordinary cast steel and tool steel bars. The larger of these racks is shown in perspective in Fig. 130. This is constructed of oak timbers formed into a rectangular frame, strongly bolted together and resting on good foundations capable of supporting the heavy weights of stock likely to be placed in the racks. Three of these frames are erected, six or seven feet apart and braced by cross braces as shown. The timbers should be 6 inches square and provided with iron supports for the bar stock. These should be spaced further apart at the bottom than at the top, the bottom space being, say, fifteen inches, and the top space eight inches, center to center of cross bars. These supports should be flat, say 3 by 11 inch for the upper three; for the next two, į by 14; and the two lower ones, i inch by 2. It may be preferred to make the three or four lower supports of 13-inch round steel, upon which are placed pieces of 14-inch gas pipe, turning freely, and so facilitating the running in and out of heavy bars. As seen in the engraving, the right-hand end of the frames may be securely bolted to the brick walls, and the cross braces on this end be omitted. At the opposite, or front end of the frames, the sill timber projects from the front of the frame about three feet, and upon this are erected heavy cast iron supports, of the form shown, which will be found very convenient for holding heavy bars, as they are open at the front, and bars may be readily lifted from the tram cars to them. Experience has shown this to be a very convenient, useful, and substantial form of bar stock rack. In place of wooden timbers cast iron supports may be used, but the cost will be much greater and the results not enough better to compensate for the added expense.
The smaller rack is built on the same plan, and may be constructed with
or without the cast iron racks in front of it. It should have substantial cross braces between its frames, and also be securely braced from the brick wall.
For a shop rack the form shown in Fig. 131 will be found very convenient.
FIG. 130. — Rack for Bar Stock, for Storing Long Bars of Iron and Steel.
The A-shaped supports are of cast iron, securely braced by cross braces bolted on as shown. The base of the supports might be made relatively narrower chan shown in the drawing without endangering their stability. Such a rack
may be made of any number of supports and placed at any desired intervals apart that the work may require. Once we have the pattern, we may make as many castings as we choose and arrange them to suit any existing conditions. Usually they should not be over 5 feet high, unless rather small and light stock is to be placed on the upper supports. The lower projecting supports may be about 10 inches long and the top ones about 7 inches.
The wash room is located in one of the rear corners, and in connection with the water-closets, which open out of it. A single wash sink of similar construction to the one illustrated and described in the article on foundry equipment is provided, and the individual lockers for the use of the men, and built of expanded metal, are arranged on both sides of the room in the usual
FIG. 131. — Small Rack for Ordinary Cast Steel and Tool Steel Bars.
manner. In the water-closets six urinals and four closet seats are provided, the latter protected by double-hinged swinging doors, and the former separated by dividing partitions two feet wide. Both should be provided with an ample supply of water for automatically flushing them. The windows lighting the wash room and water-closets are placed high enough in the wall so as not to interfere with the lockers or the urinals.
By the plans herein given all of the requirements of the operatives are placed conveniently within the building, so that whether for stock, fuel, or any reasonable cause, there is no necessity of leaving the building, as it is a well-known fact that men working near artificial heat, as do those at forges, are very sensitive to both heat and cold out of doors, and that to make proper provision for their health, comfort, and convenience, while at their work, is not only proper and commendable in itself, but always conducive to their efficiency as workmen.
Its importance in the modern machine shop. Careful planning necessary. Continuous
progress of work through the different departments. What may be classed as transportation facilities. Traveling cranes. Overhead trolleys. Shop tracks. Yard car crane. Shop trucks.
Yard tracks and cars. Cast iron track. Requirements of a floor track. An economical system of shop tracks and cars. Overcoming wheel friction on curves. Forms of wheels and track. Dimensions of track. Switches. Track timbers. Yard tracks. Track for shop floors. The turntable. Shop cars. Construction and dimensions. Various forms of shop cars.
With removable stakes. With removable boxes. With racks for special work. With trays for special work. Dump car for coal, sand, etc. Double car, two cars and a special platform. Varying dimensions of cars. Number of cars necessary.
The question of the transportation of stock and material from the point of its receipt from outside sources to the various departments where it is to begin its regular transit from the raw material to the finished product, of transferring this material from one department to another during its progress through the shops, and of, its final transit from the department where it is finished to the storehouse, for safe keeping or for shipping to customers, is an important matter. For if closely followed through all its various stages, and the expenses accurately kept, as to the capital involved in the appliances necessary, the proper maintenance of these facilities in good working condition, and the labor necessary for their successful operation, it would appear to be a far larger item of expense in the general account than would usually be supposed from a superficial consideration of the question.
This is a matter upon which careful planning is needed in all its bearings, as any saving in this respect, while still rendering good service, is an actual saving, and, unlike the reduction of the cost in building a machine for the market, is not liable to effect a deterioration of the real quality or value of the product. This does not mean that the service can, or should be, made inefficient in order to avoid expense, but rather that it should be well planned, well administered, prompt and efficient in every way, yet without a useless appliance or an unnecessary man employed in it. For instance, the progress of the work through the different departments should be so arranged that, as far as possible,
may be really progressive from the raw material to the finished product, with as little retrograde movement as may be. In this way a considerable percentage of the work of transporting materials and stock in progress may be saved, rendering a less extensive equipment of cars, trucks, etc., necessary, as well as a smaller force of employees for handling them.
In arranging the different departments of the plant here shown due consideration was given to this matter and they were carefully planned with this end in view, as will be more fully pointed out in the chapters on Machine Shop Management which will succeed this part of the work.
In the list of appliances that may be classed as transportation facilities, we may mention traveling cranes, overhead trolleys, shop cars on tracks, cars on yard tracks, hand trucks, and small tool conveyors. Of these, the traveling cranes may be those propelled by a shaft running the entire distance of their travel, by those carrying an electric motor for their propulsion, and those of small capacity worked by hand, with a chain reaching down near the floor. Again, as to lifting power, they are operated by the shaft above mentioned, by a motor, or by chain blocks with the usual differential chain wheels or other similar device.
Overhead trolleys running on I-beams may have a small motor mounted upon them furnishing the power for their propulsion as well as for their lifting power. Frequently those of moderate capacity are pulled along by hand, and the loads lifted by chain blocks operated by hand. These trolley tracks are so constructed that they can be put up in straight lines, curves, switches, crossings, etc., which render them very convenient for light work, and they occupy but little room overhead, and none at all on the floor. In some cases, however, existing overhead obstacles such as shafting, belting, countershafts, etc., preclude the use of either the overhead trolley or the traveling crane; in others the weights are not sufficient to demand the expense of a traveling crane; in still other locations several traveling cranes would be required to cover the space to be operated in. Then there are other situations in which lack of height prevents the use of the overhead trolley system.
Shop tracks for the accommodation of cars of the usual size, say 34 inches wide and 5 feet long, will be of the same gage as the yard tracks, or about 20 inches, so that the shop cars or heavier and larger yard cars may be used on the whole system. These cars may be propelled by small electric motors in the form of an electric locomotive, which is simply a car fitted with two motors operated by a storage battery, but more often they are pushed about by hand, particularly when loaded with less than 2 tons weight.
A balance crane may be erected on a car for yard or shop use, and may by this arrangement be capable of picking up and carrying a load up to a ton or two. It is very useful in locations where power for loading is not available.