of handling steel of various qualities, his expert knowledge of how to produce forgings of complicated and intricate forms, and the thousand and one conditions and requirements demanded in successfully bringing out such work, correct in form and structure, and within a reasonable cost.

In the matter of case-hardening and tempering the forge shop department has increased materially, as there has never been a time in the past when hardened and ground steel work has been as much used in the better qualities of machine construction as at present; and case-hardening has reached such an extent that it is rare to find nuts, cap screws, and the like on any well-constructed machine that are not protected from injury by this valuable process.

While the actual forging work of the forge shop has decreased its scope, it has in a general way much increased in volume, since it is now customary to add to its equipment several machine tools, such as cutting-off machines, forge lathes, heavy turret lathes, cold saws, power hack saws, and other similar machines for roughing out work, which in many instances can be much more economically done by these methods than by confining the operations to forging under the hammer. In this case the appropriate machines for these purposes are included in the equipment of the forge shop and located as will be presently described, and as shown on the plan in Fig. 123.

The foundry floor, the engine foundation, and many of the foundations for machines in the machine shop, should be kept as free from jar, and from shocks sufficiently strong to disturb the ground by vibrations, as possible. For this reason the forge shop is placed as far from these buildings as may be convenient; therefore, in the rear corner of the plant, and opposite the rear end of the machine shop. The spur track from the railroad, which supplies shipping facilities and brings to the plant the raw materials necessary for its use, runs across the rear end of the group of buildings, in the rear of the machine shop and storehouse. It continues in a curve around the rear corner and up the side to the foundry gate, rising, as it goes to a height sufficient for conveniently dumping coal, coke, molding sand, etc., into the storage sheds located along that side, the first of which is shown at the left of the forge shop in Fig. 123. The curve of the railroad track cuts off somewhat of this rear corner of the building space and therefore the forge shop is located far enough from the rear line to accommodate it, and the space so left is utilized for a one-story building containing a space for the forge coal, another for bar stock storage, and the wash room and water-closets.

The forge shop is, like the other buildings of the plant, built of brick, with steel roof construction, the roof trusses being supported in the center by steel columns. It is lighted, not only from the side windows, but from those in the monitor roof, the sashes of which are hung on pivots and controlled by cords reaching nearly to the floor, by which they may be operated when neces

FIG. 123. General Plan of Forge Shop, showing Proper Arrangement of the Machine Tools, etc.

reference to the forge shop, as well as the location of the railroad track, and Fig. 123, which also shows the contiguous buildings and their positions in sary for ventilation. The general plan of the forge shop is clearly shown in

the tram car tracks connecting this department with the railroad tracks in the rear and the other departments toward the front of the plant.

For convenience in bringing in stock and taking out finished work the tram car tracks run nearly midway through the forge shop, as shown, and are connected by their branches with the foundry, the machine shop, storage sheds, and practically all departments of the plant, as well as at three points with the railroad track, two of these being shown on the plan.

The foreman's office is located in the front corner of the shop, and has connected with it the usual foreman's store closet for such minor supplies as are more conveniently kept there than in the general storeroom near the offices. A fixed desk furnishes a convenient place for spreading out drawings, and a private desk is provided for the foreman's personal use. is a forge shop scale for weighing stock and forgings. mounted on wheels so that it can be readily moved to where it may be needed.

Outside of the office This scale should be any part of the shop

Along the outer wall of the shop are located five regular forge fires having chimney flues built into the wall for their accommodation. These latter will not be necessary if the system of down-draft forges is used. This form of forge has several good qualities, not the least of which is that it offers less obstruction in handling large pieces of work, as it may be conveniently placed at a distance from the wall if desired, and will furnish quite as good ventilating facilities in clearing the shop of coal gas as those connected with separate chimneys. The draft may be increased or decreased at the will of the operator, particularly in the case of forges manufactured by the Buffalo Forge Company, in which a hinged and adjustable hood may be closed down over a fresh fire and raised for the handling of the work to be heated, as may be desired. If these down-draft forges are used it will be necessary to provide an exhaust fan with the proper connecting pipes for carrying off the smoke and gases, which may be delivered to one chimney, thus avoiding the expense of building the other four. Such an arrangement is very clean and wholesome for the workmen, when compared with the method shown, but considerably more expensive in its first cost, as well as requiring extra power to operate it.

The forges shown on the plan should be of such construction that the tuyeres may be readily attached and detached when necessary, for cleaning or for repairs. They should have such a form of bottom valve or gate as to readily discharge the clinkers or slag that may find its way down to it. These forges are usually constructed of cast iron and supported upon four legs, so as to give convenient access beneath them for cleaning, attaching the blast pipe, repairing, etc. Each should have, cast with it, or attached to it, two narrow troughs, running the length of its front, or shortest side, for holding coal and water. Many excellent ones are in the market and can be purchased more

economically than they can be built on the premises. The blast pipe should be arranged to slide on and off easily, in case it is necessary to disconnect it for cleaning or repairs, and it should be provided with a regulating valve or gate, fitting as nearly air-tight as may be, and operated by a lever conveniently located within the reach of the operator. These forges are usually made of rectangular form, but large fires are often made upon a circular forge, whose sides extend to the floor. They need not necessarily be provided with the water and coal troughs as mentioned above, as they are usually used for heating work for the steam hammers, drop presses, and similar large work, rather than for tempering, tool forging, or small work of this class.

The blast for these forges, for the heating furnace, for the drop presses, and for the case-hardening and annealing furnace, is furnished by a fan blower designed for a pressure necessary for forge work, and having an outlet of six inches in diameter, equivalent to a No. 3 Sturtevant steel pressure blower, which is admirably adapted for this purpose. It should be located over the bench near the forges, at the front end of the shop, so that there may be no unnecessary turns or bends in the pipe leading to the forges. These pipes should be placed along the walls near the floor, but never beneath it. In one shop the author saw blast pipes, composed of vitrified drain tiles, the joints made with Portland cement, and laid less than a foot beneath the surface of a dirt floor of the forge shop, and at one point passing directly under a bolt heading machine.

As might have been expected, the jar of the shop floor broke up the pipes and destroyed their usefulness. The blast pipes should be constructed of heavy galvanized iron, well fitted and fastened, and as nearly air-tight as may be. They should be easy of access, for the possible connection of additional pipes and for convenience of making repairs, which will have to be made sooner or later. They might be placed six or seven feet high, and along the walls, but this position will necessitate about thirty feet of additional pipe, increasing the friction of the air and consequently the power required, with no especially compensating gains other than getting the pipes up out of the way somewhat.

Some of the more important rules for setting up and connecting forge blowers may be here given. Place the blower as near as possible to the forges. Make the pipe connections as direct as possible. If bends or elbows are absolutely necessary, make the curves of large radius, and with no abrupt angles; the inside radius of an elbow should not be less than twice the diameter of the pipe. Have the aggregate areas of all the outlet pipes at least equal to the delivery pipe at the blower. If the pipes must carry the air over one hundred feet, speed up the blower proportionately above the figures given in the manufacturers' catalogue. In any event, the blower should be run at

!

such a speed as will give four to five ounces pressure at the tuyeres, not less than four ounces at the forge farthest from the blower.

The blower is driven from a line shaft running the length of the shop near its center. In front of the first fire is located a large steam hammer of the arched pattern, and capable of handling work up to 10 inches in diameter. At the next fire is a smaller, single-column steam hammer of about half the capacity. The necessity of providing the larger hammer will be a matter to be decided by the size of the largest forgings to be made. For instance, if only a few forgings which come up to its capacity are to be made, it will be more economical to purchase them of some large forge shop than to provide a large hammer that may be idle much of the time. The smaller hammer should be provided for even moderate-sized work, for any plant of modern pretensions.

Next to the small hammer two drop presses are located, with a special heating furnace for use in connection with them. These drops should carry hammers weighing from 150 to 600 pounds, according to the work which they are to do.

The heating furnace need not be over 30 inches square outside, built with a cast iron shell lined with fire bricks, supported on four cast iron legs, and provided with a vertical sliding, balanced door in front. The heating chamber will be about 20 inches square and from 10 to 12 inches high. A blast pipe leads up to it, and a smoke pipe from its rear side leads to the nearest chimney. Such a furnace will heat work for drop forging much more economically and satisfactorily than the usual open forge fire. They may be purchased at a very moderate cost.

The forge fires not occupied with steam hammer work will be used for ordinary hand forging, tool forging, tool dressing, tempering, and similar work. Where much tempering of special work is necessary, that is, when a large number of pieces of the regular product of the plant is to be so treated, special arrangements as to heating furnaces, dipping baths, etc., must be provided, and in many cases special automatic heating and hardening furnaces are employed. Obviously, the great variety of this class of work precludes a detailed description in this chapter.

Near the end wall, at the rear, is located an annealing and case-hardening furnace of ample capacity. As this will be built on the premises, and as information in reference to its requirements and its construction may not be readily available, drawings have been made showing the details of its construction and giving all necessary dimensions.

While this is for a furnace of quite large capacity for a machine shop plant, a smaller one may be readily constructed on proportionate dimensions, with good and practical results. If it is to be of say one half these dimensions, or one