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Scientific American Supplement, No. 303, October 22, 1881试读：
NEW EIGHTY TON STEAM HAMMER AT THE SAINT CHAMOND WORKS
Ever since the improvements that have been introduced into the manufacture of steel, and especially into the erection of works for its production, have made it possible to obtain this metal in very large masses, it has necessarily been preferred to iron for all pieces of large dimensions, inasmuch as it possesses in the highest degree that homogeneousness and resistance which are so difficult to obtain in the latter metal. It has consequently been found necessary to construct engines sufficiently powerful to effect the forging of enormous ingots, as well as special furnaces for heating them and apparatus for manipulating and transporting them.
The greatest efforts in this direction have been made with a view to supplying the wants of heavy artillery and of naval constructions; and to these efforts is metallurgy indebted for the creation of establishments on a scale that no one would have dared a few years ago to think of. The forging mill which we are about to describe is one of those creations which is destined to remain for a long time yet very rare; and one which is fully able to respond, not only to all present exigencies, but also, as far as can be foreseen, to all those that may arise for a long period to come. The mill is constructed as a portion of the vast works that the Compagnie des Forges et Aciéries de la Marine own at Saint Chamond, and which embrace likewise a powerful steel works that furnishes, especially, large ingots exceeding 100 tons in weight.
The mill consists, altogether, of three hammers, located in the same room, and being of unequal powers in order to respond to different requirements. The largest of these hammers is of 80 tons weight, and the other two weigh respectively 35 and 28 tons. Each of them has a corresponding furnace for heating by gas, as well as cranes for maneuvering the ingots and the different engines. The general plan view in Fig. 4 shows the arrangement of the hammers, cranes, and furnaces in the millhouse.
FIG. A.--ELEVATION OF A HAMMER. FIG. B.--PROFILE VIEW
The gas generators which supply the gas-furnaces are located out of doors, as are the steam-generators. The ingots are brought from the steel factory, and the forged pieces are taken away, by special trucks running on a system of rails. We shall now give the most important details in regard to the different parts of the works.
The Mill-House--This consists of a central room, 262 feet long, 98 feet wide, and 68 feet in height, with two lean-to annexes of 16 feet each, making the total width 100 feet. The structure is wholly of metal, and is so arranged as to permit of advantage being taken of every foot of space under cover. For this purpose the system of construction without tie-beams, known as the "De Dion type," has been adopted. Fig. 1 gives a general view of one of the trusses, and Fig. 5 shows some further details. The binding-rafters consist of four angle-irons connected by cross-bars of flat iron. The covering of corrugated galvanized iron rests directly upon the binding-rafters, the upper parts of which are covered with wood for the attachment of the corrugated metal. The spacing of these rafters is calculated according to the length of the sheets of corrugated iron, thus dispensing with the use of ordinary rafters, and making a roof which is at once very light and very durable, and consequently very economical. Rain falling on the roof flows into leaden gutters, from whence it is carried by leaders into a subterranean drain. The vertical walls of the structure are likewise of corrugated iron, and the general aspect of the building is very original and very satisfactory.
The 80 Ton Hammer--The three hammers, notwithstanding their difference in power, present similar arrangements, and scarcely vary except in dimensions. We shall confine ourselves here to a description of the 80 ton apparatus. This consists, in addition to the hammer, properly so called, of three cranes of 120 tons each, serving to maneuver the pieces to be forged, and of a fourth of 75 tons for maneuvering the working implements. These four cranes are arranged symmetrically around the hammer, and are supported at their upper extremity by metallic stays. Besides the foregoing there are three gas furnaces for heating the ingots. Figs. 1, 2, and 3 show the general arrangement of the apparatus.
Foundations of the Hammer and Composition of the Anvil-Bed--To obtain a foundation for the hammer an excavation was made to a depth of 26 feet until a bed of solid rock was reached, and upon this there was then spread a thick layer of beton, and upon this again there was placed a bed of dressed stones in the part that was to receive the anvil-stock and hammer.
On this base of dressed stones there was placed a bed formed of logs of heartwood of oak squaring 16 inches by 3 feet in height, standing upright, joined together very perfectly, and kept in close juxtaposition by a double band of iron straps joined by bolts. The object of this wooden bed was to deaden, in a great measure, the effect of the shock transmitted by the anvil-stock.
NEW EIGHTY-TON STEAM HAMMER AT THE ST CHAMOND WORKS.
FIG. 1.--TRANSVERSE SECTION.
FIG. 2.--PLAN.
FIG. 3.--PROFILE VIEW.
FIG. 4.--GENERAL PLAN OF THE FORGING MILL.
FIG. 5.--DETAILS OF THE TRUSSAND SUPPORT FOR THE CRANE.
The Anvil-Stock.--The anvil-stock, which is pyramidal in shape, and the total weight of which amounts to 500 tons, is composed of superposed courses, each formed of one or two blocks of cast iron. Each course and every contact was very carefully planed in order to make sure of a perfect fitting of the parts; and all the different blocks were connected by means of mortises, by hot bandaging, and by joints with key-pieces, in such a way as to effect a perfect solidity of the parts and to make the whole compact and impossible to get out of shape.
The anvil-stock was afterwards surrounded by a filling-in of masonry composed of rag-stones and a mortar made of cement and hydraulic lime. This masonry also forms the foundation for the standards of the hammer, and is capped with dressed stone to receive the bed-plates.
The Power-Hammer (Figs. A and B).--The power-hammer, properly so-called, consists, in addition to the hammer-head, of two standards to whose inner sides are bolted guides upon which slides the moving mass. The bed-plates of cast iron are 28 inches thick, and are independent of the anvil-stock. They are set into the bed of dressed stone capping the foundation, and are connected together by bars of iron and affixed to the masonry by foundation bolts. To these bedplates are affixed the standards by means of bolts and keys. The two standards are connected together by iron plates four inches in thickness, which are set into the metal and bolted to it so as to secure the utmost strength and solidity. The platform which connects the upper extremities of the standards supports the steam cylinder and the apparatus for distributing the steam. The latter consists of a throttle valve, twelve inches in diameter, and an eduction valve eighteen inches in diameter, the maneuvering of which is done by means of rods extending down to a platform upon which the engineman stands. This platform is so situated that all orders can be distinctly heard by the engineman, and so that he shall be protected from the heat radiated by the steel that is being forged. All the maneuvers of the hammers are effected with most wonderful facility and with the greatest precision.
The piston is of cast-steel, and the rod is of iron, 12 inches in diameter. The waste steam is carried out of the mill by a pipe, and, before being allowed to escape into the atmosphere, is directed into an expansion pipe which it penetrates from bottom to top. Here a portion of the water condenses and flows off, and the steam then escapes into the open air with a greatly diminished pressure. The object of this arrangement is to diminish to a considerable extent the shocks and disagreeable noise that would be produced by the direct escape of the steam at quite a high pressure and also to avoid the fall of condensed water.
The following are a few details regarding the construction of the hammer: Total height of foundations........... 26 ft. From the ground to the platform ...... 28 " Platform .............................. 3.25 " Height of cylinder.................... 21 " ________ Total height...................... 78.25 ft. Weight of anvil-stock................ 500 tons. Weight of bed-plates................. 122 " Weight of standards.................. 270 " Weight of platform and cylinder...... 148 " Piston, valves, engineman's platform, hammer, etc........................ 160 " __________ Total weight................... 1,200 tons. Weight of the hammer.................. 80 tons. Maximum fall.......................... 25.75 ft. Distance apart of the standards....... 21.6 " Width of hammer....................... 6 " Pressure of steam..................... 16 lb. Effective pressure to lift 80 tons.... 7 "
Description of Figures.--A, the 80-ton hammer; B, B1, B2, cranes; C, C1, C2, supports of cranes; D, D1, D2, gas furnaces; A1, the 35-ton hammer; A2, the 28-ton hammer; EE, railways; F, engineman's platform; G, lever for maneuvering the throttle valve; H, an ingot being forged.
GREAT STEAMERS.
The Brooklyn Eagle gives a very interesting description of the three new steamships now almost completed and shortly to be placed in the New York and Liverpool trade by the Cunard, Inman, and Williams and Guion lines. The writer has prepared a table comparing the three vessels with each other and with the Great Eastern, the only ship of greater dimensions ever built. We give as much of the article as our space will allow, and regret that we have not the room to give it entire: Line. Cunard. Inman. Guion. Admiralty. Vessel. Servia City of Rome. Alaska. Great[1] Length 530 feet. 546 feet. 520 feet. 679 feet. Breadth 52 feet. 52 ft. 3 in. 50 ft. 6 in. 82 feet. Depth 44 ft. 9 in. 37 feet. 38 feet. 60 feet. Gross ton'ge 8,500 8,300 8,000 13,344[2] Horse pow'r 10,500 10,000 11,000 2,600 Speed 17½ knots. 18 knots. 18 knots. 14 knots. Sal'n pas- 320 and 52 sengers. 450 300 2d class Steerage 600 1,500 1,000 Where Clydeb'nk Barrow in Clyde, built. Thomson Furness Elder Date of sailing. October 22 October 13 November 5
[Footnote 1: To be sold at auction soon.]
[Footnote 2: Net register.]
In 1870 the total tonnage of British steam shipping was 1,111,375; the returns for the year 1876 showed an increase to 2,150,302 tons, and from that time to the present it has been increasing still more rapidly. But, as can be seen from the above table, not only has the total tonnage increased to this enormous extent, but an immense advance has been made in increasing the size of vessels. The reason for this is, that it has been found that where speed is required, along with large cargo and passenger accommodation, a vessel of large dimensions is necessary, and will give what is required with the least proportionate first cost as well as working cost. Up to the present time the Inman line possessed, in the City of Berlin, of 5,491 tons, the vessel of largest tonnage in existence. Now, however, the Berlin is surpassed by the City of Rome by nearly 3,000 tons, and the latter is less, by 200 tons, than the Servia, of the Cunard line. It will be observed, too, that while there is not much difference between the three vessels in point of length, the depth of the Alaska and the City of Rome, respectively, is only 38 feet and 37 feet, that of the Servia is nearly 45 feet as compared with that of the Great Eastern of 60 feet. This makes the Servia, proportionately, the deepest ship of all. All three vessels are built of steel. This metal was chosen not only because of its greater strength as against iron, but also because it is more ductile and the advantage of less weight is gained, as will be seen when it is mentioned that the Servia, if built of iron, would have weighed 620 tons more than she does of steel, and would have entailed the drawback of a corresponding increase in draught of water. As regards rig, the three vessels have each a different style. The Cunard Company have adhered to their special rig--three masts, bark rigged--believing it to be more ship shape than the practice of fitting up masts according to the length of the ship. On these masts there is a good spread of canvas to assist in propelling the ship. The City of Rome is rigged with four masts; and here the handsome full-ship rig of the Inman line has been adhered to, with the addition of the fore and aft rigged jigger mast, rendered necessary by the enormous length of the vessel. It will be seen that the distinctive type of the Inman line has not been departed from in respect to the old fashioned but still handsome profile, with clipper bow, figurehead, and bowsprit--which latter makes the Rome's length over all 600 feet. For the figurehead has been chosen a full length figure of one of the Roman Cæsars, in the imperial purple. Altogether, the City of Rome is the most imposing and beautiful sight that can be seen on the water. The Alaska has also four masts, but only two crossed.
The length of the City of Rome, as compared with breadth, insures long and easy lines for the high speed required; and the depth of hold being only 37 feet, as compared with the beam of 52 feet, insures great stability and the consequent comfort of the passengers. A point calling for special notice is the large number of separate compartments formed by water tight bulkheads, each extending to the main deck. The largest of these compartments is only about 60 feet long; and, supposing that from collision or some other cause, one of these was filled with water, the trim of the vessel would not be materially affected. With a view to giving still further safety in the event of collision or stranding, the boilers are arranged in two boiler rooms, entirely separated from each other by means of a water tight iron bulkhead. This reduces what, in nearly all full-powered steamships, is a vast single compartment, into two of moderate size, 60 feet in length; and in the event of either boiler room being flooded, it still leaves the vessel with half her boiler power available, giving a speed of from thirteen to fourteen knots per hour. The vessel's decks are of iron, covered with teak planking; while the whole of the deck houses, with turtle decks and other erections on the upper deck, are of iron, to stand the strains of an Atlantic winter. Steam is supplied by eight cylindrical tubular boilers, fired from both ends, each of the boilers being 19 feet long and having 14 feet mean diameter. There are in all forty eight furnaces. The internal arrangements are of the finest description. There are two smoking rooms, and in the after deckhouse is a deck saloon for ladies, which is fitted up in the most elegant manner, and will prevent the necessity of going below in showery weather. At the sides of the hurricane deck are carried twelve life boats, one of which is fitted as a steam launch. The upper saloon or drawing-room is 100 feet long, the height between decks being 9 feet. The grand dining-saloon is 52 feet long, 52 feet wide, and 9 feet high, or 17 feet in the way of the large opening to the drawing-room above. This opening is surmounted by a skylight, and forms a very effective and elegant relief to the otherwise flat and heavy ceiling. There are three large and fourteen small dining tables, the large tables being arranged longitudinally in the central part of the saloon, and the small tables at right angles on the sides. Each diner has his own revolving arm chair, and accommodation is provided for 250 persons at once. A large American organ is fixed at the fore end of the room, and opening off through double spring doors at the foot of the grand staircase is a handsome American luncheon bar, with the usual fittings. On each side of the vessel, from the saloon to the after end of the engine room, are placed staterooms providing for 300 passengers. The arrangements for steerage passengers are of a superior description. The berths are arranged in single tiers or half rooms, not double, as is usually the custom, each being separated by a passage, and having a large side light, thus adding greatly to the light, ventilation, and comfort of the steerage passengers, and necessitating the advantage of a smaller number of persons in each room. The City of Rome is the first of the two due here; she sails from Liverpool on October 13.
In the Servia the machinery consists of three cylinder compound surface condensing engines, one cylinder being 72 inches, and two 100 inches in diameter, with a stroke of piston of 6 feet 6 inches. There are seven boilers and thirty-nine furnaces. Practically the Servia is a five decker, as she is built with four decks--of steel, covered with yellow pine--and a promenade reserved for passengers. There is a music room on the upper deck, which is 50 feet by 22 feet, and which is handsomely fitted up with polished wood panelings. For the convenience of the passengers there are no less than four different entrances from the upper deck to the cabins. The saloon is 74 feet by 49 feet, with sitting accommodations for 350 persons, while the clear height under the beams is 8 feet 6 inches. The sides are all in fancy woods, with beautifully polished inlaid panels, and all the upholstery of the saloon is of morocco leather. For two-thirds of its entire length the lower deck is fitted up with first class staterooms. The ship is divided into nine water-tight bulkheads, and she is built according to the Admiralty requirements for war purposes. There are in all twelve boats equipped as life-boats. The Servia possesses a peculiarity which will add to her safety, namely, a double bottom, or inner skin. Thus, were she to ground on rocks, she would be perfectly safe, so long as the inner skin remained intact. Steam is used for heating the cabins and saloons, and by this means the temperature can be properly adjusted in all weathers. In every part of the vessel the most advanced scientific improvements have been adopted. The Servia leaves Liverpool on October 22.
The Alaska, whose owners, it is understood, are determined to make her beat all afloat in speed, does not sail until November 5, and therefore it is premature to say anything about her interior equipments. She is the sister of the celebrated Arizona, and was built by the well-known firm of Elder & Co., on the Clyde.
IMPROVED ROAD LOCOMOTIVE.
Several attempts have been made to connect the leading wheels of a traction engine with the driving wheels, so as to make drivers of all of them, and thus increase the tractive power of the engine, and to afford greater facilities for getting along soft ground or out of holes. The wheels with continuous railway and India-rubber tires have been employed to gain the required adhesion, but these wheels have been too costly, and the attempts to couple driving and leading wheels have failed. The arrangement for making the leading wheels into drivers, illustrated on page 4825, has been recently brought out by the Durham and North Yorkshire Steam Cultivation Company, Ripon, the design being by Messrs. Johnson and Phillips. The invention consists in mounting the leading axle in a ball and long socket, the socket being rotated in fixed bearings. The ball having but limited range of motion in the socket, is driven round with it, but is free to move in azimuth for steering.
This engine has now been in use more than twelve months in traction and thrashing work, and, we are informed, with complete success. The illustrations represent a 7-horse power, with a cylinder 8 in. diameter by 12 in. stroke, and steam jacketed. The shafts and axles are of Bowling iron. The boiler contains 140 ft. of heating surface, and is made entirely of Bowling iron, with the longitudinal seams welded. The gearing is fitted with two speeds arranged to travel at 1½ and 3 miles per hour, and the front or hind road wheels can be put out of gear when not required. The hind driving wheels are 5 ft. 6 in. diameter, and the front wheels 5 ft.; weight of engine 8 tons.--The Engineer.
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