Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: Do steam locomotives have gears?
A geared steam locomotive is a type of steam locomotive which uses gearing, usually reduction gearing, in the drivetrain, as opposed to the common directly driven design.
With the decline of the commercial use of steam traction, the commercial use of geared locomotives has similarly reduced.
Developments after the separate expansion valve led to more sophisticated valve gears that could achieve the same goal of varying inlet lap with a single valve. The first of these were the link valve gears, particularly the Stephenson link valve gear. This uses a pair of eccentrics with a sliding link mechanism between them that acts as a mechanical adding device. Selecting intermediate positions provides a valve actuation with the effect of increasing cut-off. As such valve gears also provided, and were first developed for, reversing, they were widely used on locomotives. Theoretically, the precise effect is that of reduced valve "travel", rather than an "earlier" cut-off. This has the effect of reducing overall valve opening, reducing initial steam supply and so having the effect of wire-drawing rather than pure expansion. Despite this, the Stephenson gear became one of the two most-widely used gears for locomotives.
There were various types of articulated geared steam locomotive, including:There are several classes of articulated electric locomotives of generally two types:
Electric and diesel bogie locomotives have many construction aspects in common with Meyer type steam locomotives but are not seen as articulated.
On engines with outside cylinders there are three possible variations:There are three common variations:There are three common variations:There are many other variations, e.g. geared steam locomotives which may have only one cylinder.
The only conventional steam locomotive with one cylinder that is known is the Nielson One-Cylinder Locomotive.
The first new loco was built in 1976. To date (2008) over eighty locos have been built – steam, diesel and electric. Most have been miniature or narrow gauge except for two standard gauge steam locos for Beamish Museum – the replicas of "Steam Elephant" and "Puffing Billy". In 2008 Alan Keef Ltd built the frames, running gear and mechanical parts for two Parry People Mover railcars for use on the Stourbridge Town branch (139001 and 139002). A number of Alan Keef's locomotives are replicas of steam locomotives but with diesel power. These are referred to as "steam outline" (s/o) in the listing below.
Cass Scenic Railroad State Park Glossary of steam locomotive components Steam donkey Steam motor
Whilst at Mechelen in 1844 he developed a new type of valve gear (a mechanism that allows for adjustment of the travel of the valves that distribute the steam to the cylinders and enables a steam locomotive to be put into reverse and to economise steam). He was not permitted by the company to patent the device himself as he was deemed of too lowly a rank. An engineer colleague and friend, M. Fisher, applied for the patent on his behalf but never claimed any contribution to it. Walschaerts name on the documents erroneously omitted the final 's' causing confusion over its correct spelling over the succeeding years. A locomotive built at the Tubize workshops fitted with the Walschaerts valve gear was awarded a gold medal at the 1873 Universal Exhibition in Vienna. This valve gear came to be used in the majority of steam locomotives, and became almost universal throughout the 20th Century.
No geared steam locomotives remain in commercial use in America. However, several are in operation on tourist lines.
Poppet valves have been used on steam locomotives, often in conjunction with Lentz or Caprotti valve gear. British examples include:Sentinel Waggon Works used poppet valves in their steam wagons and steam locomotives. Reversing was achieved by a simple sliding camshaft system.
A booster engine for steam locomotives is a small two-cylinder steam engine back-gear-connected to the trailing truck axle on the locomotive or, if none, the lead truck on the tender. A rocking idler gear permits it to be put into operation by the engineer. It would drive one axle only and could be non-reversible with one idler gear or reversible with two idler gears.
As with many of the Pennsylvania Railroad's steam locomotives, the J1 had its headlight above the smokebox. Like the M1 the J1 had a keystone numberplate, unlike the round numberplates seen on the rest of the PRR's freight steam locomotives. They were also equipped with Baker valve gear instead of Walschaerts valve gear which was more common on the PRR. Additionally, they had radial-stay fireboxes instead of the Belpaire fireboxes seen on nearly all of the Pennsylvania Railroad's steam locomotives. Mechanically, these locomotives were identical to the C&O's T-1 class 2-10-4s.
This gearing is part of the machinery within the locomotive and should not be confused with the pinion that propels a rack locomotive along the rack between the rails. The geared steam locomotives that have been built have been for conventional track, relying on the adhesion between wheels and rail.
Because, today, locomotives no longer tend to have separate driving and carrying axles (see wheel arrangement), as was formerly common with steam locomotives, but usually have bogies where all axles are driven, the term running gear is (inaccurately) superseding the term 'driving gear' in some parts of the world.
The generally accepted smallest gauge for a live steam locomotive is Gauge 1, although O scale live steam models are also common. Producing smaller-scale models remains problematic, as the laws of physics do not themselves scale: creating a small-scale boiler that produces useful quantities of steam requires careful engineering. Hornby Railways has produced commercial live steam-powered locomotives in OO scale by utilising an electrically heated boiler mounted in the tender, with cylinders in the locomotive, and control provided by electrical- signals fed through the track from a remote control unit. They are less mechanically realistic than models in larger scales; the visible valve gear is a dummy, as on the electric-motor-powered models, and steam admission to the cylinders is controlled by a rotary-valve servo inside the boiler casing, which is also a dummy. Nevertheless, the locomotive is driven by steam that is created on board the locomotive and is hence a genuine "steam" locomotive.
A steam turbine locomotive is a steam locomotive which transmits steam power to the wheels via a steam turbine. Numerous attempts at this type of locomotive were made, mostly without success. In the 1930s this type of locomotive was seen as a way both to revitalize steam power and challenge the diesel locomotives then being introduced.
There are two ways to drive the wheels: either directly via gears, or using generator-driven traction motors.
Joy's valve-gear was used extensively on Lancashire and Yorkshire Railway and London and North Western Railway locomotives, and also on the Manning Wardle-built narrow gauge 2-6-2 locomotives of the Lynton and Barnstaple Railway. Joy gear was also used by John Fowler & Co. and several other steam traction engine manufacturers. The most numerous locomotive class using Joy valve gear was Russian O class, in O and O variants (over 4500 built) - a letter "d" / "D" in their designations stood for Joy (in Russian phonetically: Джой - Dzhoy). Joy's valve gear was used in the Doble steam car until replaced by Stephenson's valve gear.
Some geared steam locomotives are still at work in the sugar plantations of Indonesia, and no doubt elsewhere too, but in most countries they may now be seen only on tourist lines, preservation sites and museums. The particular advantage in cane sugar operations is the ability to use the dried solid residue of pressing the cane (see bagasse) as a fuel of trivial cost, providing that low cost technical labor is available to maintain the locomotives.
The Shay locomotive was the most widely used geared steam locomotive. The locomotives were built to the patents of Ephraim Shay, who has been credited with the popularization of the concept of a "geared steam locomotive". Although the design of Ephraim Shay's early locomotives differed from later ones, there is a clear line of development that joins all Shays.
Articulated Beyer-Garratt Cab forward Double Fairlie Duplex Electric-steam locomotive Geared steam locomotive Heilmann locomotive High-pressure steam locomotive Mallet 5AT Advanced Technology Steam Locomotive Steam dummy Steam turbine locomotive Triplex
The Sentinel Waggon Works built numerous geared shunting locomotives to several designs mainly with vertical water-tube boilers and high-speed, enclosed, poppet-valve engines. These combined high-pressure boilers with high-reduction gearing to provide high torque at low speeds.[2] The Willamette locomotive was an improved-upon clone of the Shay locomotive produced in limited number by Willamette Iron & Steel (better known for their steam donkey engines) after key patents expired. West coast logging customers were clamoring for improvements in detail design and the application of more modern locomotive technology to the geared locomotive; Lima (manufacturers of the Shay) were dragging their heels. The Willamette was the response to that. A & G Price Ltd of Thames, New Zealand built a number of geared locomotives, often home-grown variants of the Climax A, Climax B or Heisler types. They did however produce a type that is known as the "16-wheeler" (0-4-4-4-4-0) that was also produced by another NZ manufacturer, Johnson Brothers of Invercargill. Price's last steam engine was a Heisler locomotive, built 3 years after the last American Heisler was built. Aveling and Porter built a few geared locomotives which were, essentially, traction engines with flanged wheels. The early ones used sprocket chain drive but later versions had spur gears. The Avonside Engine Company produced a small number of narrow gauge geared steam locomotives for sugar cane plantations in Natal. These were similar in design to Heislers. The Kitson-Still locomotive used different ends of the same cylinders for steam or diesel propulsion. The crank was above the frame and a gear train of fixed reduction linked it to the centre axle. Vertical boilered "coffee-pot" locomotives were often geared, though those made by De Winton were not.
The Walschaerts valve gear is a type of valve gear invented by Belgian railway mechanical engineer Egide Walschaerts in 1844 used to regulate the flow of steam to the pistons in steam engines. The gear is sometimes named without the final "s", since it was incorrectly patented under that name. It was extensively used in steam locomotives from the late 19th century until the end of the steam era.
These restrictions do not apply to marine or stationary steam engines due to not having size or weight restrictions. Ships often had massive waste steam recovery systems, such as the 400 ton waste steam turbine used to recover very low 6psi waste steam on the Titanic and its sister ships. This is several times the weight of an entire locomotive, and so is clearly not feasible as a form of waste steam recovery for locomotives.
The Heisler locomotive has a 'Vee-Twin' style steam engine, one cylinder each side of the boiler, affixed to a centrally located longitudinal driveshaft, again geared to the wheels.
These were not the first locomotives to use geared transmission. Richard Trevithick's Coalbookdale Locomotive used a large gear instead of side rods to link the crankshaft to the driving axles, with a net 1:1 gear ratio. The early Grasshopper (1832), Crab (1837) and Mud Digger (1842) locomotives built for the Baltimore and Ohio Railroad used gear ratios on the order of 2:1 so that each turn of the crankshaft caused about two turns of the driving axles. This allowed use of relatively small driving wheels without sacrificing speed.[1]