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81-407: USCGC Eagle may refer to: USCGC  Eagle  (1925) , was a "100-foot" Eagle -class patrol boat , commissioned in 1925 and transferred to the U.S. Navy in 1936 USCGC  Eagle  (WIX-327) , is a Gorch Fock -class barque originally commissioned as Segelschulschiff Horst Wessel , a German training vessel taken as war reparations by

162-639: A vertical beam or overhead beam , and sometimes simply referred as a "beam", was another early adaptation of the beam engine, but its use was confined almost entirely to the United States. After its introduction, the walking beam quickly became the most popular engine type in American waters for inland waterway and coastal service, eventually making its way into American transoceanic steamships as well. The type proved to have remarkable longevity, with walking beam engines still being occasionally manufactured as late as

243-417: A beam (i.e. walking beam, side-lever or grasshopper) engine. The later definition only uses the term for engines that apply power directly to the crankshaft via the piston rod and/or connecting rod. Unless otherwise noted, this article uses the later definition. Unlike the side-lever or beam engine, a direct-acting engine could be readily adapted to power either paddlewheels or a propeller. As well as offering

324-457: A centrally located crankshaft. Back-acting engines were another type of engine popular in both warships and commercial vessels in the mid-19th century, but like many other engine types in this era of rapidly changing technology, they were eventually abandoned for other solutions. There is only one known surviving back-acting engine—that of the TV Emery Rice (formerly USS  Ranger ), now

405-492: A common, T-shaped crosshead. The vertical arm of the crosshead extended down between the two cylinders and was attached at the bottom to both the crankshaft connecting rod and to a guide block that slid between the vertical sides of the cylinders, enabling the assembly to maintain the correct path as it moved. The Siamese engine was invented by British engineer Joseph Maudslay (son of Henry ), but although he invented it after his oscillating engine (see below), it failed to achieve

486-544: A compound engine gave a significant increase in fuel efficiency, so allowing steamships to out-compete sail on the route from the UK to China, even before the opening of the Suez Canal in 1869. A triple-expansion engine is a compound engine that expands the steam in three stages, e.g. an engine with three cylinders at three different pressures. A quadruple-expansion engine expands the steam in four stages. However, as explained above,

567-468: A compound walking beam type, compound being the cylinder technology, and walking beam being the connection method. Over time, as most engines became direct-acting but cylinder technologies grew more complex, engines began to be classified solely according to cylinder technology. More commonly encountered marine steam engine types are listed in the following sections. Note that not all these terms are exclusive to marine applications. The side-lever engine

648-541: A continuously moving assembly line like automobiles. The size of the craft made this too difficult, however, and a "step-by-step" movement was instituted on the 1,700-foot (520 m) line, entailing seven separate assembly areas, followed by the addition of a 200-foot (61 m) extension to the assembly facility, or B-Building, to support a pre-assembly stage. Unfortunately, the Eagles suffered from various issues due to Ford's institutional inexperience with shipbuilding: for instance,

729-430: A different design operating at only 90 psi (620 kPa). This was insufficient to fully realise the economic benefits of triple expansion. Aberdeen was fitted with two double ended Scotch type steel boilers, running at 125 psi (860 kPa). These boilers had patent corrugated furnaces that overcame the competing problems of heat transfer and sufficient strength to deal with the boiler pressure. This provided

810-497: A fundamental nature to the design concept. First, Ford engineers built a full-scale pattern at the company's Highland Park facility , giving both the Ford team and the Naval officers an opportunity to correct flaws in the rough initial design and decide on the placement of all rivet holes in the craft, as well as allowing the carmaker's production experts the chance to compose specifications for

891-474: A lower profile, direct-acting engines had the advantage of being smaller and weighing considerably less than beam or side-lever engines. The Royal Navy found that on average a direct-acting engine (early definition) weighed 40% less and required an engine room only two thirds the size of that for a side-lever of equivalent power. One disadvantage of such engines is that they were more prone to wear and tear and thus required more maintenance. An oscillating engine

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972-729: A ship's economy or its speed. Broadly speaking, a compound engine can refer to a steam engine with any number of different-pressure cylinders—however, the term usually refers to engines that expand steam through only two stages, i.e., those that operate cylinders at only two different pressures (or "double-expansion" engines). Note that a compound engine (including multiple-expansion engines, see below) can have more than one set of variable-pressure cylinders. For example, an engine might have two cylinders operating at pressure x and two operating at pressure y, or one cylinder operating at pressure x and three operating at pressure y. What makes it compound (or double-expansion) as opposed to multiple-expansion

1053-421: A short range and were not particularly seaworthy due to their weight, low power, and tendency to break down, but they were employed successfully along rivers and canals, and for short journeys along the coast. The first successful transatlantic crossing by a steamship occurred in 1819 when Savannah sailed from Savannah, Georgia to Liverpool, England . The first steamship to make regular transatlantic crossings

1134-407: A side-rod, extended down each side of the cylinder to connect to the end of the side-lever on the same side. The far ends of the two side-levers were connected to one another by a horizontal crosstail, from which extended a single, common connecting rod which operated the crankshaft as the levers rocked up and down around the central pin. The main disadvantage of the side-lever engine was that it

1215-503: A small, low-profile engine like the trunk engine to power the U.S. Federal government's monitors , a type of warship developed during the American Civil War that had very little space for a conventional powerplant. The trunk engine itself was, however, unsuitable for this purpose, because the preponderance of weight was on the side of the engine that contained the cylinder and trunk—a problem that designers could not compensate for on

1296-415: A smaller, lighter, more efficient design. In a steeple engine, the vertical oscillation of the piston is not converted to a horizontal rocking motion as in a beam engine, but is instead used to move an assembly, composed of a crosshead and two rods, through a vertical guide at the top of the engine, which in turn rotates the crankshaft connecting rod below. In early examples of the type, the crosshead assembly

1377-462: Is also an alternative name for the steeple engine (below). Many sources thus prefer to refer to it by its informal name of "square" engine to avoid confusion. Additionally, the marine crosshead or square engine described in this section should not be confused with the term " square engine " as applied to internal combustion engines , which in the latter case refers to an engine whose bore is equal to its stroke . The walking beam, technically known as

1458-401: Is that the engine could be easily started from any crank position. Like the conventional side-lever engine however, grasshopper engines were disadvantaged by their weight and size. They were mainly used in small watercraft such as riverboats and tugs . The crosshead engine, also known as a square , sawmill or A-frame engine, was a type of paddlewheel engine used in the United States. It

1539-438: Is that there are only two pressures , x and y. The first compound engine believed to have been installed in a ship was that fitted to Henry Eckford by the American engineer James P. Allaire in 1824. However, many sources attribute the "invention" of the marine compound engine to Glasgow 's John Elder in the 1850s. Elder made improvements to the compound engine that made it safe and economical for ocean-crossing voyages for

1620-855: The Hawaiian Islands in 1921 before being supplanted by larger ships. Eagle boat 34, as related in Max Miller's 1932 book I Cover The Waterfront , shared the yearly duty alternately with the Navy tug USS  Koka of capturing elephant seals on Mexico's Guadalupe Island for the San Diego Zoo . Five of the Eagle Boats were transferred to the United States Coast Guard in 1919 but proved unsuitable for service because poor maneuvering characteristics and sea-keeping qualities. The balance were sold in

1701-624: The River Rouge on the outskirts of Detroit , he proposed to turn them out as factory products, using mass production techniques, and employing factory workers. He would then send the boats by the Great Lakes and the St. Lawrence River to the Atlantic coast. However, Ford had little part in the design of the boats. Except for his insistence upon simple plans and the use of steam turbines, he contributed little of

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1782-417: The beam engine . The typical side-lever engine had a pair of heavy horizontal iron beams, known as side-levers, each secured in the centre by a pin near the base of the engine, allowing the levers to pivot through a limited arc. The engine cylinder stood vertically between this pair of levers at one end, with the piston rod attached to a horizontal crosshead above, from each end of which a vertical rod, known as

1863-519: The 1830s and the type was perfected in the early 1840s by the Scottish shipbuilder David Napier . The steeple engine was gradually superseded by the various types of direct-acting engine. The Siamese engine, also referred to as the "double cylinder" or "twin cylinder" engine, was another early alternative to the beam or side-lever engine. This type of engine had two identical, vertical engine cylinders arranged side-by-side, whose piston rods were attached to

1944-577: The 1930s and early 1940s. Eight Eagle boats saw service during World War II. One was stationed in Miami as a training vessel., while one, Eagle 56 , was sunk by a German submarine near Portland, Maine in April 1945. After the war, the seven remaining Eagle Boats were decommissioned. PE-61 through PE-112 were canceled on 30 November 1918. PE-5, PE-15, PE-25, PE-45, PE-65, PE-75, PE-86, PE-95, PE-105, and PE-112 were allotted for transfer to Italy, though this plan

2025-504: The 1940s. In marine applications, the beam itself was generally reinforced with iron struts that gave it a characteristic diamond shape, although the supports on which the beam rested were often built of wood. The adjective "walking" is believed to have originated from a corruption of the technical term "working beam". Walking beam engines were a type of paddlewheel engine and were rarely used for powering propellers. They were used primarily for ships and boats working in rivers, lakes and along

2106-526: The Eagle Boats never saw service in World War I . Reports on their performance at sea were mixed. The introduction, at Ford's insistence, of flanged plates instead of rolled plates facilitated production but resulted in sea-keeping characteristics which were far from ideal. In the first years after the war, a number of them were used as aircraft tenders. Despite the handicap of their size, they serviced photographic reconnaissance planes at Midway in 1920 and in

2187-701: The Eagle class sought to remedy. They were originally commissioned USS Eagle Boat No.1 (or 2,3..etc.) but this was changed to PE-1 (or 2,4.. etc.) in 1920. They never officially saw combat in World War I, but some were used during the Allied intervention in the Russian Civil War . PE-19, 27, 32, 38, 48 and 55–57 survived to be used in World War II . Attention turned to building steel patrol vessels. In their construction, it

2268-484: The Model T did not use electric arc welding , and the resulting workmanship on the Eagle boats was so poor that the superintending constructor requested that Ford workers do as little welding as possible on water-tight and oil-tight bulkheads. Additionally, the use of ladders instead of scaffolds caused major difficulties—the attempted bolting of plates, carried out by workers wielding short-handled wrenches on ladders meant that

2349-521: The Navy's plans for the projected steel patrol ships, Ford urged that all hull plates be flat so that they could be produced quickly in quantity and he also persuaded the Navy to accept steam turbines instead of reciprocating steam engines . At this point, Secretary of the Navy Josephus Daniels was drawn into the project. He recognized that no facilities were available at the Navy yards for building new craft and asked Ford if he would undertake

2430-655: The United States Navy that were built during World War I using mass production techniques. They were steel-hulled ships smaller than contemporary destroyers but having a greater operational radius than the wooden-hulled, 110-foot (34 m) submarine chasers developed in 1917. The submarine chasers' range of about 900 miles (1,400 km) at a cruising speed of 10 knots (19 km/h; 12 mph) restricted their operations to off-shore anti-submarine work and denied them an open-ocean escort capability; their high consumption of gasoline and limited fuel storage were handicaps

2511-462: The United States and commissioned into the Coast Guard in 1946; she is still in active service See also [ edit ] USRC  Eagle USS  Eagle [REDACTED] [REDACTED] List of ships with the same or similar names This article includes a list of ships with the same or similar names. If an internal link for a specific ship led you here, you may wish to change

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2592-509: The United States and in Ericsson's native country of Sweden, and as they had few advantages over more conventional engines, were soon supplanted by other types. The back-acting engine, also known as the return connecting rod engine , was another engine designed to have a very low profile. The back-acting engine was in effect a modified steeple engine, laid horizontally across the keel of a ship rather than standing vertically above it. Instead of

2673-412: The assembly maintained the correct path as it moved. The engine's alternative name—"A-frame"—presumably derived from the shape of the frames that supported these guides. Some crosshead engines had more than one cylinder, in which case the piston rods were usually all connected to the same crosshead. Because the cylinder was above the crankshaft in this type of engine, it had a high center of gravity, and

2754-408: The bolters were unable to apply sufficient force to bring the plates together tightly. Metal shavings between plates then made the riveters' task of pulling the plates together for a seal practically impossible. The first Eagle boat was launched on 11 July. The launching of these 200-foot (61 m) craft was a formidable operation. Not built on slipways from which they could slide into the water,

2835-475: The centerpiece of a display at the American Merchant Marine Museum . As steamships grew steadily in size and tonnage through the course of the 19th century, the need for low profile, low centre-of-gravity engines correspondingly declined. Freed increasingly from these design constraints, engineers were able to revert to simpler, more efficient and more easily maintained designs. The result was

2916-457: The close of the 19th century. Because they became so common, vertical engines are not usually referred to as such, but are instead referred to based upon their cylinder technology, i.e. as compound, triple-expansion, quadruple-expansion etc. The term "vertical" for this type of engine is imprecise, since technically any type of steam engine is "vertical" if the cylinder is vertically oriented. An engine someone describes as "vertical" might not be of

2997-635: The coastline, but were a less popular choice for seagoing vessels because the great height of the engine made the vessel less stable in heavy seas. They were also of limited use militarily, because the engine was exposed to enemy fire and could thus be easily disabled. Their popularity in the United States was due primarily to the fact that the walking beam engine was well suited for the shallow- draft boats that operated in America's shallow coastal and inland waterways. Walking beam engines remained popular with American shipping lines and excursion operations right into

3078-435: The conservatism of American domestic shipbuilders and shipping line owners, who doggedly clung to outdated technologies like the walking beam and its associated paddlewheel long after they had been abandoned in other parts of the world. The steeple engine, sometimes referred to as a "crosshead" engine, was an early attempt to break away from the beam concept common to both the walking beam and side-lever types, and come up with

3159-765: The course of the 19th century. The two main methods of classifying such engines are by connection mechanism and cylinder technology . Most early marine engines had the same cylinder technology (simple expansion, see below) but a number of different methods of supplying power to the crankshaft (i.e. connection mechanism) were in use. Thus, early marine engines are classified mostly according to their connection mechanism. Some common connection mechanisms were side-lever, steeple, walking beam and direct-acting (see following sections). However, steam engines can also be classified according to cylinder technology (simple-expansion, compound, annular etc.). One can therefore find examples of engines classified under both methods. An engine can be

3240-443: The cramped spaces on the boats themselves, and violated Ford's own mass production ethos. The original expectation, set out in a contract between Ford and the Navy on 1 March 1918, was for delivery of 100 ships: "one by mid-July, ten by mid-August, twenty by mid-September, and twenty-five each month thereafter," or approximately one new Eagle boat completed each working day of the month. The first seven boats were not completed until

3321-424: The crankshaft rotated—hence the term, oscillating . Steam was supplied and exhausted through the trunnions. The oscillating motion of the cylinder was usually used to line up ports in the trunnions to direct the steam feed and exhaust to the cylinder at the correct times. However, separate valves were often provided, controlled by the oscillating motion. This let the timing be varied to enable expansive working (as in

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3402-410: The early 20th century. Although the walking beam engine was technically obsolete in the later 19th century, it remained popular with excursion steamer passengers who expected to see the "walking beam" in motion. There were also technical reasons for retaining the walking beam engine in America, as it was easier to build, requiring less precision in its construction. Wood could be used for the main frame of

3483-556: The end of 1918, and succeeding boats were plagued by issues such as leaky fuel oil compartments. This state of affairs continued, even though the labor force reached 4,380 by July and later peaked at 8,000. The chief reasons were Ford's excessive initial optimism and the inexperience of labor and supervisory personnel in shipbuilding. Upon the signing of the Armistice in November 1918 , the number under contract, previously raised from 100 to 112,

3564-412: The engine in the paddle ship PD Krippen ). This provides simplicity but still retains the advantages of compactness. The first patented oscillating engine was built by Joseph Maudslay in 1827, but the type is considered to have been perfected by John Penn . Oscillating engines remained a popular type of marine engine for much of the 19th century. The trunk engine, another type of direct-acting engine,

3645-517: The engine, at a much lower cost than typical practice of using iron castings for more modern engine designs. Fuel was also much cheaper in America than in Europe, so the lower efficiency of the walking beam engine was less of a consideration. The Philadelphia shipbuilder Charles H. Cramp blamed America's general lack of competitiveness with the British shipbuilding industry in the mid-to-late 19th century upon

3726-404: The first Royal Navy steam vessel in 1820 until 1840, 70 steam vessels entered service, the majority with side-lever engines, using boilers set to 4psi maximum pressure. The low steam pressures dictated the large cylinder sizes for the side-lever engines, though the effective pressure on the piston was the difference between the boiler pressure and the vacuum in the condenser. The side-lever engine

3807-543: The first time. To fully realise their benefits, marine compound engines required boiler pressures higher than the limit imposed by the United Kingdom 's Board of Trade , who would only allow 25 pounds per square inch (170 kPa). The shipowner and engineer Alfred Holt was able to persuade the authorisation of higher boiler pressures, launching SS  Agamemnon in 1865, with boilers running at 60 psi (410 kPa). The combination of higher boiler pressures and

3888-424: The growing dominance of the so-called "vertical" engine (more correctly known as the vertical inverted direct acting engine). In this type of engine, the cylinders are located directly above the crankshaft, with the piston rod/connecting rod assemblies forming a more or less straight line between the two. The configuration is similar to that of a modern internal combustion engine (one notable difference being that

3969-691: The gunboat type exists in the Western Australian Museum in Fremantle . After sinking in 1872, it was raised in 1985 from the SS ; Xantho and can now be turned over by hand. The engine's mode of operation, illustrating its compact nature, could be viewed on the Xantho project's website. The vibrating lever, or half-trunk engine, was a development of the conventional trunk engine conceived by Swedish - American engineer John Ericsson . Ericsson needed

4050-493: The higher boiler pressures that became prevalent in the latter half of the 19th century due to the difficulty of maintaining a steam seal around the trunk, and builders abandoned them for other solutions. Trunk engines were normally large, but a small, mass-produced, high-revolution, high-pressure version was produced for the Crimean War. In being quite effective, the type persisted in later gunboats. An original trunk engine of

4131-625: The hope of getting him to serve on the United States Shipping Board . Wilson felt that Ford, with his knowledge of mass production techniques, could immensely speed the building of ships in quantity. Apprised of the need for anti-submarine vessels to combat the U-boat menace, Ford replied, "what we want is one type of ship in large numbers." On 7 November, Ford accepted membership on the Shipping Board and an active advisory role. Examining

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4212-418: The hulls moved slowly from the assembly line on enormous, tractor-drawn flatcars. They were then placed on a 225-foot (69 m) steel trestle alongside the water's edge which could be sunk 20 feet (6.1 m) into the water by hydraulic action. The plan was to fit the Eagles out with all the basic equipment of a warship—turbines, weaponry, wiring, etc.--after launch, but this quickly became a choke point due to

4293-583: The link to point directly to the intended ship article, if one exists. Retrieved from " https://en.wikipedia.org/w/index.php?title=USCGC_Eagle&oldid=1046800693 " Categories : Set index articles on ships Ships of the United States Coast Guard Hidden categories: Articles with short description Short description is different from Wikidata All set index articles Eagle-class patrol craft The Eagle-class patrol craft were anti-submarine vessels of

4374-500: The literature of the early period then, an engine can generally be assumed to be simple-expansion unless otherwise stated. Compound engines were a method of improving efficiency. Until the development of compound engines, steam engines used the steam only once before it was recycled back to the boiler. A compound engine first recycles the steam into one or more larger, lower-pressure secondary cylinders, to use more of its heat energy. Compound engines could be configured to increase either

4455-459: The location of the lever pivot and connecting rod are more or less reversed, with the pivot located at one end of the lever instead of the centre, while the connecting rod is attached to the lever between the cylinder at one end and the pivot at the other. Chief advantages of the grasshopper engine were cheapness of construction and robustness, with the type said to require less maintenance than any other type of marine steam engine. Another advantage

4536-612: The manufacturing and assembly processes. The assembly plant was completed in five months, and the first keel was laid in May 1918. The machinery and fittings were largely built at Ford's Highland Park plant in Detroit, although the new River Rouge plant, given impetus by the war, saw a good deal of the steel sheets and other parts formed and fabricated there in the A-Building, or fabricating building. At first, Ford believed that boats could be sent down

4617-656: The number of expansion stages defines the engine, not the number of cylinders, e.g. the RMS Titanic had four-cylinder, triple-expansion engines. The first successful commercial use was an engine built at Govan in Scotland by Alexander C. Kirk for the SS  Aberdeen in 1881. An earlier experiment with an almost identical engine in SS Propontis in 1874 had had problems with the boilers. The initial installation, running at 150 psi (1,000 kPa) had to be replaced with

4698-636: The rivalry in 1790 after his successful test resulted in a passenger service on the Delaware River. In 1807, the American Robert Fulton built the world's first commercially successful steamboat, simply known as the North River Steamboat , and powered by a Watt engine. Following Fulton's success, steamboat technology developed rapidly on both sides of the Atlantic . Steamboats initially had

4779-455: The same widespread acceptance, as it was only marginally smaller and lighter than the side-lever engines it was designed to replace. It was however used on a number of mid-century warships, including the first warship fitted with a screw propeller, HMS  Rattler . There are two definitions of a direct-acting engine encountered in 19th-century literature. The earlier definition applies the term "direct-acting" to any type of engine other than

4860-475: The side-to-side motion of the connecting rod, which links a gudgeon pin at the piston head to an outside crankshaft. The walls of the trunk were either bolted to the piston or cast as one piece with it, and moved back and forth with it. The working portion of the cylinder is annular or ring-shaped, with the trunk passing through the centre of the cylinder itself. Early examples of trunk engines had vertical cylinders. However, ship builders quickly realized that

4941-406: The small monitor warships. Ericsson resolved this problem by placing two horizontal cylinders back-to-back in the middle of the engine, working two "vibrating levers", one on each side, which by means of shafts and additional levers rotated a centrally located crankshaft. Vibrating lever engines were later used in some other warships and merchant vessels, but their use was confined to ships built in

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5022-514: The standards of the war era or the present," and today serves as a case study in the history of technology to illustrate the difficulty in transferring knowledge and techniques between superficially similar, but fundamentally different, fields of endeavor. The term "Eagle Boat" stemmed from a wartime editorial in The Washington Post which called for "...an eagle to scour the seas and pounce upon and destroy every German submarine." However,

5103-436: The steam engine is double acting, see below, whereas almost all internal combustion engines generate power only in the downward stroke). Vertical engines are sometimes referred to as "hammer", "forge hammer" or "steam hammer" engines, due to their roughly similar appearance to another common 19th-century steam technology, the steam hammer . Vertical engines came to supersede almost every other type of marine steam engine toward

5184-596: The steam engine to marine applications in England would have to wait until almost a century after Newcomen, when Scottish engineer William Symington built the world's "first practical steamboat ", the Charlotte Dundas , in 1802. Rivaling inventors James Rumsey and John Fitch were the first to build steamboats in the United States. Rumsey exhibited his steamboat design in 1787 on the Potomac River; however, Fitch won

5265-508: The task. Ford agreed, and, in January 1918, he was directed to proceed with the building of 100 of them. Later on, 12 more were added for delivery to the Italian government. The first boat was launched on 11 July 1918. According to Ford, "They were built simply by applying our production principles to a new product." Ford's plan for building the ships was revolutionary. Establishing a new plant on

5346-404: The technical solution that ensured that virtually all newly built ocean-going steamships were fitted with triple expansion engines within a few years of Aberdeen coming into service. Multiple-expansion engine manufacture continued well into the 20th century. All 2,700 Liberty ships built by the United States during World War II were powered by triple-expansion engines, because the capacity of

5427-411: The triangular crosshead assembly found in a typical steeple engine however, the back-acting engine generally used a set of two or more elongated, parallel piston rods terminating in a crosshead to perform the same function. The term "back-acting" or "return connecting rod" derives from the fact that the connecting rod "returns" or comes back from the side of the engine opposite the engine cylinder to rotate

5508-543: The type was compact enough to lay horizontally across the keel . In this configuration, it was very useful to navies, as it had a profile low enough to fit entirely below a ship's waterline , as safe as possible from enemy fire. The type was generally produced for military service by John Penn. Trunk engines were common on mid-19th century warships. They also powered commercial vessels, where—though valued for their compact size and low centre of gravity—they were expensive to operate. Trunk engines, however, did not work well with

5589-420: The vertical inverted direct-acting type, unless they use the term "vertical" without qualification. A simple-expansion engine is a steam engine that expands the steam through only one stage, which is to say, all its cylinders are operated at the same pressure. Since this was by far the most common type of engine in the early period of marine engine development, the term "simple expansion" is rarely encountered. In

5670-485: Was a paddlewheel engine and was not suitable for driving screw propellers . The last ship built for transatlantic service that had a side-lever engine was the Cunard Line 's paddle steamer RMS  Scotia , considered an anachronism when it entered service in 1862. The grasshopper or 'half-lever' engine was a variant of the side-lever engine. The grasshopper engine differs from the conventional side-lever in that

5751-406: Was a type of direct-acting engine that was designed to achieve further reductions in engine size and weight. Oscillating engines had the piston rods connected directly to the crankshaft, dispensing with the need for connecting rods. To achieve this, the engine cylinders were not immobile as in most engines, but secured in the middle by trunnions that let the cylinders themselves pivot back and forth as

5832-574: Was cancelled and none were ever delivered. [REDACTED]   This article incorporates text from the public domain Dictionary of American Naval Fighting Ships . See here for text Marine steam engine The first commercially successful steam engine was developed by Thomas Newcomen in 1712. The steam engine improvements brought forth by James Watt in the later half of the 18th century greatly improved steam engine efficiency and allowed more compact engine arrangements. Successful adaptation of

5913-570: Was cut to 60. Of these, seven were commissioned in 1918, and the remaining 53 were commissioned in 1919. The entire Eagle Boat operation came briefly under challenge by Senator Henry Cabot Lodge of Massachusetts in December 1918. At the ensuing Congressional hearings, Navy officials successfully defended the boats as being a necessary experiment and well made while Ford profits were proved to be modest. However, historian David Hounshell states that "the Eagle boat venture cannot be considered successful by

5994-464: Was large and heavy. For inland waterway and coastal service, lighter and more efficient designs soon replaced it. It remained the dominant engine type for oceangoing service through much of the first half of the 19th century however, due to its relatively low centre of gravity , which gave ships more stability in heavy seas. It was also a common early engine type for warships, since its relatively low height made it less susceptible to battle damage. From

6075-525: Was necessary to eliminate the established shipbuilding facilities as possible sources of construction as they were totally engaged in the building of destroyers, larger warships, and merchant shipping. Accordingly, a design was developed by the Bureau of Construction and Repair which was sufficiently simplified to permit speedy construction by less experienced shipyards. In June 1917, President Woodrow Wilson had summoned auto-builder Henry Ford to Washington in

6156-404: Was originally developed as a means of reducing an engine's height while retaining a long stroke . (A long stroke was considered important at this time because it reduced the strain on components.) A trunk engine locates the connecting rod within a large-diameter hollow piston. This "trunk" carries almost no load. The interior of the trunk is open to outside air, and is wide enough to accommodate

6237-619: Was rectangular in shape, but over time it was refined into an elongated triangle. The triangular assembly above the engine cylinder gives the engine its characteristic "steeple" shape, hence the name. Steeple engines were tall like walking beam engines, but much narrower laterally, saving both space and weight. Because of their height and high centre of gravity, they were, like walking beams, considered less appropriate for oceangoing service, but they remained highly popular for several decades, especially in Europe, for inland waterway and coastal vessels. Steeple engines began to appear in steamships in

6318-511: Was the sidewheel steamer Great Western in 1838. As the 19th century progressed, marine steam engines and steamship technology developed alongside each other. Paddle propulsion gradually gave way to the screw propeller , and the introduction of iron and later steel hulls to replace the traditional wooden hull allowed ships to grow ever larger, necessitating steam power plants that were increasingly complex and powerful. A wide variety of reciprocating marine steam engines were developed over

6399-470: Was the first type of steam engine widely adopted for marine use in Europe . In the early years of steam navigation (from c1815), the side-lever was the most common type of marine engine for inland waterway and coastal service in Europe, and it remained for many years the preferred engine for oceangoing service on both sides of the Atlantic . The side-lever was an adaptation of the earliest form of steam engine,

6480-406: Was the most common type of engine in the early years of American steam navigation. The crosshead engine is described as having a vertical cylinder above the crankshaft, with the piston rod secured to a horizontal crosshead, from each end of which, on opposite sides of the cylinder, extended a connecting rod that rotated its own separate crankshaft. The crosshead moved within vertical guides so that

6561-433: Was therefore deemed unsuitable for oceangoing service. This largely confined it to vessels built for inland waterways. As marine engines grew steadily larger and heavier through the 19th century, the high center of gravity of square crosshead engines became increasingly impractical, and by the 1840s, ship builders abandoned them in favor of the walking beam engine. The name of this engine can cause confusion, as "crosshead"

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