fourth the capacity, the lower heating ducts will be single instead of double, and it will be preferable to build it with a cast iron casing inclosing all four sides, forming the door frames, and the separate pieces being bolted together at the corners, instead of having the brickwork held together by binders and rods as shown in the drawings.

H

The construction is clearly shown in Figs. 124, 125, and 126, being respectively a front, side, and a rear elevation. Fig. 127 is a crosssection through the fire box A, showing the bridge wall B, the form of the covering arch F, and the position of the blast pipe G. Fig. 128 is a longitudinal section showing the fire box A, heating chamber C, heating ducts D, D, and sections of the front and rear doors. Fig. 129 is a crosssection through the heating chamber C, the heating ducts D, D, dividing wall M, and the main door N. The foundation should be laid deep enough to support the weight of the furnace and its charge, and will be quite similar to that provided for boiler settings. The shaded portions indicate fire bricks, the balance being ordinary, hard, red bricks. The grate bars are of any convenient pattern, but must

11/

LL

FIG. 124. Front Elevation of Annealing and
Case-hardening Furnace

G

FIG. 125.

Side Elevation of Annealing and Case-hardening Furnace.

have ample air spaces so as not to impede the air blast delivered through the blast pipe G. The top arch is of fire brick and is carried all the way through both front and back walls, for convenience in making repairs upon it.

The floor of the heating chamber is composed of fire brick tiles 5 inches thick, 9 inches wide, and 24 inches long, their outer ends supported by the inwardly projecting side walls, and their inner ends by the dividing wall M.

They are laid about an inch apart so as to permit the gases and smoke to pass down between them to the heating ducts D, D, and out through the smoke pipe attached to the rear door L. The frame and door of the fire box are from the same pattern as the rear door K, while the frame of the ash pit door J, and the smoke door L, are from the same pattern. The doors are different, of course, as the door I must be provided with a circular sleeve to which the smoke pipe is attached, its other end connecting with the nearest chimney. annealing boxes are introduced and

The main door N, through which the removed, is of special construction and fitted with a fire-brick lining, perforated by a circular opening or "peek hole," and held in place by four

-5′6′′

4
B

A

S-Rad.

bolts (as shown in Fig. 125), which pass through iron straps on the inside of the fire brick lining. The stopper P is of tubular form and has an inwardly-projecting flange at its inner end for the purpose of holding the lining, which is composed of fire clay packed in as solidly as possible while it is slightly wet. This stopper may be removed at any time to obtain a view of the interior of the heating chamber and its contents during a heat, as all the FIG. 127. doors are tightly closed and the cracks luted with fire clay as soon as the fire is well under way, one charge of coal being usually sufficient for the heat after the furnace has been heated up.

BLAST PIPE

Section through Fire Box, etc., of Annealing and Case-hardening Furnace.

The blast pipe furnishing the blast for the forges will also supply this furnace, the pressure required being the same, and will be connected to the fixture G located in the wall of the ash pit for that purpose.

Such a furnace as has just been described will, if properly built, and with occasional repairs to the fire brick lining, last many years. The author knows of one which was built twenty years ago that is in serviceable condition at the present time.

On the opposite side of the central columns is located the group of machines for roughing out stock, the first being a heavy cutting-off machine capable of taking in stock up to six inches in diameter and cutting it off to any required length. In this machine there should be two tools fed automatically, and the machine should be provided with a convenient speed-changing device whereby the surface cutting speed may be maintained constant at all diameters, as this latter feature will materially increase the output of the machine.

FIG. 128.

Longitudinal Section of Annealing and Case-hardening Furnace.

Next to this machine are two cutting-off machines of a capacity for 4-inch stock and arranged similarly to the larger machine. They are so placed as to be conveniently operated by one man.

Next to these machines are two power hack saws, provided for cutting off square and flat stock. These should carry from 12 to 15 inch saws, and while apparently slow-working machines are capable of cutting off a large quantity of stock in proportion to the labor cost of attendance.

Located near the large cutting-off machine is the cold saw, which will serve for stock or forgings beyond the capacity of the cutting-off machine or the power hack saws, and will often save much valuable time in finishing up a forging. The saws in these machines are from 12 to 40 inches in diameter, the former size cutting off stock up to 3 inches in diameter, and the latter handling 13-inch stock. For this case the saw should be 20 inches in diameter, and capable of cutting off 7-inch stock. There are many of these saws in the market and apparently not very much choice between them, all conditions being considered.

K)

The shear, located next to the cold saw, is not generally as much used as before the power hack saw came into notice, yet in certain classes of rough work it is very useful and operates quickly. It should be able to cut off round stock up to one inch, square stock to the same size, and flat stock to half inch by two.

F

N

In the heavy turret lathe much work may be roughed out from the bar and sent to the machine shop in a more satisfactory condition than if it had been forged, and at the same time it will do the work more economically. It should take in stock up to 3 inches in diameter and be provided with a heavy, open, hexagonal turret, bored so as to allow the stock to pass entirely through it if necessary. If should also be provided with heavy roughing tools somewhat similar to box tools, as well as a heavy cutting-off slide adjustably supported on the bed.

C

K

E

E

M

D

OPENING 24 x 34°

Section through Heating Chamber of
Annealing and Case-hardening Furnace.

The forge lathe, located next to the turret lathe, will be useful in rough-turning spindles and similar

heavy work, and doing it much cheaper than forging the work down to close dimensions. It should be built for cuts of 6 or 8 to the inch, and a cutting speed from 100 feet per minute and slower.

A short work bench and vise is provided at each end of the line of forges for the convenience of the blacksmiths, and a much longer one on the opposite side for the men running the machine tools, which should have three vises upon it.

A supply of steam will be needed for the steam hammers, and may be brought from the power house in a conduit, the pipes being properly protected by a non-conducting covering to prevent, as far as possible, the loss of heat. But these hammers may be operated by compressed air, which will not be subjected to such loss. And as power will be required to run the line shafting driving the various machines, it may be more economical to bring in a current of electricity with which to drive one or more motors, by which the line shafting may be driven and from which a small air compressor may be operated, thus bringing the power within the building and under the control of the foreman in charge of it. This plan would seem more advisable than the other. If an air compressor is used it may be located between the shear and the scale, and the reservoir connected with it placed directly overhead.

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 purpose, rather than to place it on the floor level, where it will be subjected to dirt and accidental injury.

the

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 casily 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 by 1 inch for the upper three; for the next two, by 13; and the two lower ones, 1 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 1-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