U. S. Battleship Delaware - Description of Machinery - Official Trials
U. S. BATTLESHIP DELAWARE
By CAPT. R. T. HALL, U. S. N.
The battleship Delaware, built by the Newport News Shipbuilding and Dry Dock Co., Newport News, Va., is one of two sister ships, the other being the North Dakota, built by the Fore River Shipbuilding Co., of Quincy, Mass. The contract for this vessel was signed August 6, 1907, the price being $3,987,000, which does not include the armor and armor bolts (exclusive of protective deck), ordnance and ordnance outfit and certain articles supplied by the Government. The contract time for completion was thirty-six months.
The main engines were required to develop twenty-six thousand five hundred horsepower when working one hundred and thirty revolutions per minute, with a steam pressure of two hundred and sixty-five pounds at the high-pressure cylinder.
The guaranteed speed of the ship was twenty-one knots per hour for four hours.
PRINCIPAL DIMENSIONS OF HULL
| Length on Normal Load Water Line, Feet and Inches | 510 - 00 |
| Between Perpendiculars, Feet and Inches | 510 - 00 |
| Overall, Feet and Inches | 518 - 09 |
| Breadth, Molded, Feet and Inches | 84 - 10 1/4 |
| Extreme, to Outside Plating | 85 - 02 5/8 |
| Trial displacement, Tons | 20,000 |
| Displacement Per Inch Immersion, at Normal Draught, Tons | 71.6 |
| Capacity of Engine Room Feed Tanks, Tons | 39 |
| Reserve Feed Water Compartments, Tons | 221.4 |
There are two propelling engines, right and left, outboard turning when going ahead, and placed abreast in watertight compartments, separated by a middle-line bulkhead.
The engines are of the vertical, inverted-cylinder, direct acting, four-cylinder, triple-expansion type. The order of the cylinders, beginning forward, is forward low pressure, high pressure, intermediate and after low pressure. The cranks of the two forward engines are opposite, as are the cranks of the two after engines, the first pair being set at right angles with the second. The sequence of the cranks, therefore, is high pressure, intermediate pressure, forward low pressure and after low pressure.
The framing of the engines consists of forged columns trussed by forged-steel stays.
The engine bedplates are of cast steel, in three sections, supported on the keelson plates, and have seatings for the main bearings, columns and the turning engines.
The cylinders and valve chests are of the best quality of cast iron, fitted with working liners of c1ose-grained cast iron as hard as can be properly worked. All cylinders are steam jacketed around the working liners and the intermediate and low-pressure cylinders at both ends. The steam is supplied at boiler pressure to the high-pressure cylinder jackets and through reducing valves for the intermediate and low pressure jackets, successively, each having its respective drain through a trap to the feed tanks.
The high-pressure and the intermediate-pressure cylinders touch at finished surfaces so disposed as to offer constraint against athwartship motion only.
On the casings flanges are cast for securing lagging. There are facings for the crosshead guides and other fittings, and there are brackets for the supporting columns and the tie rods.
The high-pressure piston is made of cast iron, the intermediate and the low-pressure pistons of cast steel, and all followers are of class "A” cast steel.
The high and intermediate-pressure piston rings are solid the low-pressure rings are cut obliquely and fitted with a brass tongue piece and lug, over which is fitted a limiting piece. All the rings are set out with “C” springs, each having equal tension.
Each piston rod is tapered to fit the piston and it is secured by a nut having a locking plate. The lower end is fitted to a forged-steel crosshead to which is bolted a cast-steel slipper. This slipper is lined with white metal and works in a single guide bolted to the cylinder facings at the upper end and to a cast-steel guide of "I" section at the lower end; this girder is supported by the inboard engine columns.
The go-ahead guides are iron castings and are made hollow to contain a water jacket; the backing guides are of cast-steel and bolted to the flanges on the go-ahead guides.
The connecting rods are high-grade steel forgings, forked at the top to span the crosshead, and are "T" headed at the bottom.
The crank shafts are in two sections, each carrying two cranks, coupling disk and raised seatings for the eccentrics. The latter are made in two parts, bolted firmly in place and secured by a key with adjusting pieces on either side.
The forward section of the crank shaft operates a shaft bilge pump.
The main valves are of the piston type, one for the high pressure and two for the intermediate and low-pressure cylinders.
The heads are of cast steel with lap-welded steel-pipe distance pieces riveted on; the packing rings are of cast iron turned larger than the bore of the valve chest, cut obliquely and bolted together to allow contraction but not expansion.
The valve stems carry balance pistons working in cylinders on the upper valve-chest cover; the tops of the high and of intermediate-pressure balance pistons are connected to the low-pressure receiver and the tops of the low-pressure balance pistons are connected to the main exhaust pipe.
The bottom of the high-pressure valve stem carries composition gibs working in brackets secured to the lower valve chest covers. The intermediate and the low-pressure valve stems are worked by a crosshead similarly guided. The valve gear is of the Stephenson type, with double—bar links and an independent linking arrangement on the reversing shaft.
USS Delaware Engine Room General Arrangement
The reversing gear for each engine consists of a steam cylinder and an oil-controlling cylinder bolted to the high-pressure cylinder. The piston rod of the reversing gear, which is common to both cylinders, acts directly on the arm, keyed to the reversing shaft. The piston rod passes through the controlling cylinder with a uniform diameter.
The valve of the steam cylinder is of the piston pattern, of composition, working in composition-lined valve chest.
There is a by-pass valve on the oil cylinder, worked by a continuation of the stem of the steam-piston valve. These valves are worked by a floating lever, the primary motion being derived from the hand lever on the working platform and the secondary motion from the reversing shaft, all parts being so adjusted that the reversing shaft follows the motion of the hand lever and is firmly held when stopped. There is a stopcock in the by-pass pipe of the oil cylinder, and a pump for reversing by hand is connected to the oil cylinder with its lever convenient to the working platform. The by-pass pipes are connected to the valve box of the hand pump in such a way as to leave the hand arrangement always in gear. The piston of the oil cylinder is packed by two cup leathers.
There is one reversing shaft for each engine, with an axial hole through it. It has arms for the reversing engine and for each link. Each reversing arm for the links is made with a slot fitted with a block, to which the extension links are attached. Each block is adjustable in the slot of its arm by a screw and hand wheel of an approved hand-locking device and is fitted with a suitable index. The slots in these arms are so arranged that the links may be thrown into full backward gear, irrespective of the position of the block in the slot; and the length of the slots is such that cut-off may be varied from about 0.5 to 0.83 of the stroke.
There is installed in each engine room a double engine for turning the main engine with steam of one hundred pounds pressure. This engine drives, by worm gearing, a second worm, which may be made, at will, to mesh with a worm wheel fitted on the crank shaft.
The turning engines have piston valves, and are made reversible by means of Stephenson links, reversed by hand levers.
Each turning-engine shaft is fitted for turning by hand.
Water service is provided for each engine by a 3 ½ -inch pipe from the discharge side of the main circulating pump. This pipe has suitable branches to the various parts of the engine; the discharge is returned to the suction side of the same pump by suitable pipe connections.
The oil service is supplied with oil from a gravity tank fed by a small steam pump with overflow pipe to the pump suction. The piping arrangement is such that oil is distributed to all the oil boxes, which have adjusting valves and wick feed to pipes leading to all bearings except those served by the forced-lubrication system.
Each main engine is provided with its own system of forced lubrication, each system consisting of three steam oil pumps, one main-supply oil tank and one water and oil-settling tank, together with the necessary piping, valves and filters. The crank pits are of oiltight construction, fitted with an oil well, and are so designed that no bilge water or dirt can enter therein. An oil trough is thus formed at the base of each engine to catch all the oil. The tops of the crank pits are covered with a light sheet-iron casing to prevent splashing and waste of oil, but allowing sufficient clearance for the oscillation of the connecting and eccentric rods.
The pumps of each system are designated by A, B and C. Pump A draws oil from the main supply tank and discharges same through oil filters to the main bearings only. Pump B is arranged primarily to draw oil from the crank-pit oil well and discharge same through filters to the main supply tank. The filters are provided in triplicate, two intended to be used at a time, while the other is being overhauled and cleaned. This pump can also be used as an auxiliary on the water suction from oil well, with delivery to settling tank. Pump C is in the nature of a standby, principally intended to draw water and oil from the oil well and discharge same to settling tank, but it is also arranged to perform the duties of both the other pumps in case of emergency.
The plant operates as follows: Pump A draws the oil from the main supply tank and discharges same through a pipe leading to the main engine and through branch pipes to the main bearings. The branch pipes conduct the oil to the bearings through holes in the bearing caps. Annular grooves in the bearings provide for the proper distribution of the oil throughout the main bearings, the oil passing through a radial hole in each journal to the axial holes of the crank shaft. The openings at the end of axial holes are closed by oiltight cover plates. From the crank-shaft axial holes the oil is forced through radial holes to the crank-pin axial holes and through radial holes to the surface of the crank pins. The crosshead pins are provided with swivel joints and pipes and valves so arranged that either forced lubrication or the water surface can be used on the crosshead pins. All other parts of the engine are oiled in the usual manner, by gravity flow supplied from manifolds and cups. Ordinarily the crosshead pins are oiled in like manner, instead of being connected to the forced system. After performing its function the oil is forced out at the ends of the bearings and drains to the crank pit, which, as stated, serves the purpose of a trough for catching the oil. From the crank-pit oil well the oil is drawn by the pump B and delivered through oil filters to the main supply tank, thus completing its cycle, which is repeated indefinitely as described.
Whenever the oil shows signs of water, due to water-service waste and other sources, the pump C is put on the water suction from the oil well and discharges to the settling tank, from which, after allowing to settle, the oil is drained off to the crank pit and the water to the bilge. The settling tank has no suction connection to any pump.
Pressure gauges are provided to show the pressure at which the oil is supplied. Thermometers are also fitted in the main bearing caps for taking the temperature of the bearings, etc. Large storage tanks are provided for making up leakage and other waste and for replenishing the entire system when desired.