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Crosshead Vs Trunk
In mechanical engineering, a crosshead is a mechanical joint used as part of the slider-crank linkages of long reciprocating engines (either internal combustion or steam) and reciprocating compressors to eliminate sideways force on the piston. Also, the crosshead enables the connecting rod to freely move outside the cylinder. Because of the very small bore-to-stroke ratio on such engines, the connecting rod would hit the cylinder walls and block the engine from rotating if the piston was attached directly to the connecting rod like on trunk engines. Therefore, the longitudinal dimension of the crosshead must be matched to the stroke of the engine. Overview On smaller engines, the connecting rod links the piston and the crankshaft directly, but this transmits sideways forces to the piston, since the crankpin (and thus the direction the force is applied) moves from side to side with the rotary motion of the crank. These transverse forces are tolerable in a smaller engine. A large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crosshead Bearing
In mechanical engineering, a crosshead is a mechanical joint used as part of the slider-crank linkages of long reciprocating engines (either internal combustion or steam) and reciprocating compressors to eliminate sideways force on the piston. Also, the crosshead enables the connecting rod to freely move outside the cylinder. Because of the very small bore-to-stroke ratio on such engines, the connecting rod would hit the cylinder walls and block the engine from rotating if the piston was attached directly to the connecting rod like on trunk engines. Therefore, the longitudinal dimension of the crosshead must be matched to the stroke of the engine. Overview On smaller engines, the connecting rod links the piston and the crankshaft directly, but this transmits sideways forces to the piston, since the crankpin (and thus the direction the force is applied) moves from side to side with the rotary motion of the crank. These transverse forces are tolerable in a smaller engine. A large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crankpin
A crankpin or crank pin, also known as a rod bearing journal, is a mechanical device in an engine which connects the crankshaft to the connecting rod for each cylinder. It has a cylindrical surface, to allow the crankpin to rotate relative to the "big end" of the connecting rod. The most common configuration is for a crankpin to serve one cylinder. However, many V engines have each crankpin shared by each pair of cylinders. Design The crankpin connects to the larger end of the connecting rod for each cylinder. This end of the connecting rod is called the "big end", as opposed to the "small end" or "little end" (which connects to the wrist/gudgeon pin in the piston). The bearing which allows the crankpin to rotate around its shaft is called the "rod bearing". In automotive engines, the most common type of rod bearing is the plain bearing, however Bushing (bearing), bushings or roller bearings are also used in some engines. Configurations In a single-cylinder engine, strai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bearings (mechanical)
A bearing is a machine element that constrains relative motion to only the desired motion, and reduces friction between moving parts. The design of the bearing may, for example, provide for free linear movement of the moving part or for free rotation around a fixed axis; or, it may ''prevent'' a motion by controlling the vectors of normal forces that bear on the moving parts. Most bearings facilitate the desired motion by minimizing friction. Bearings are classified broadly according to the type of operation, the motions allowed, or to the directions of the loads (forces) applied to the parts. Rotary bearings hold rotating components such as shafts or axles within mechanical systems, and transfer axial and radial loads from the source of the load to the structure supporting it. The simplest form of bearing, the ''plain bearing'', consists of a shaft rotating in a hole. Lubrication is used to reduce friction. In the ''ball bearing'' and ''roller bearing'', to reduce slidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engine Technology
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power generation), heat energy (e.g. geothermal), chemical energy, electric potential and nuclear energy (from nuclear fission or nuclear fusion). Many of these processes generate heat as an intermediate energy form, so heat engines have special importance. Some natural processes, such as atmospheric convection cells convert environmental heat into motion (e.g. in the form of rising air currents). Mechanical energy is of particular importance in transportation, but also plays a role in many industrial processes such as cutting, grinding, crushing, and mixing. Mechanical heat engines convert heat into work via various thermodynamic processes. The internal combustion engine is perhaps the most common example of a mechanical heat engine, in whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crosshead Piston
A piston is a component of reciprocating engines, reciprocating pumps, gas compressors, hydraulic cylinders and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod. In a pump, the function is reversed and force is transferred from the crankshaft to the piston for the purpose of compressing or ejecting the fluid in the cylinder. In some engines, the piston also acts as a valve by covering and uncovering ports in the cylinder. __TOC__ Piston engines Internal combustion engines An internal combustion engine is acted upon by the pressure of the expanding combustion gases in the combustion chamber space at the top of the cylinder. This force then acts downwards through the connecting rod and onto the crankshaft. The connecting rod is attached ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Side-lever
A marine steam engine is a steam engine that is used to power a ship or boat. This article deals mainly with marine steam engines of the reciprocating type, which were in use from the inception of the steamboat in the early 19th century to their last years of large-scale manufacture during World War II. Reciprocating steam engines were progressively replaced in marine applications during the 20th century by steam turbines and marine diesel engines. History 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 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. Ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Steam Engine
A marine steam engine is a steam engine that is used to power a ship or boat. This article deals mainly with marine steam engines of the reciprocating type, which were in use from the inception of the steamboat in the early 19th century to their last years of large-scale manufacture during World War II. Reciprocating steam engines were progressively replaced in marine applications during the 20th century by steam turbines and marine diesel engines. History 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 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. Ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steam Locomotive
A steam locomotive is a locomotive that provides the force to move itself and other vehicles by means of the expansion of steam. It is fuelled by burning combustible material (usually coal, oil or, rarely, wood) to heat water in the locomotive's boiler to the point where it becomes gaseous and its volume increases 1,700 times. Functionally, it is a steam engine on wheels. In most locomotives, the steam is admitted alternately to each end of its cylinders, in which pistons are mechanically connected to the locomotive's main wheels. Fuel and water supplies are usually carried with the locomotive, either on the locomotive itself or in a tender coupled to it. Variations in this general design include electrically-powered boilers, turbines in place of pistons, and using steam generated externally. Steam locomotives were first developed in the United Kingdom during the early 19th century and used for railway transport until the middle of the 20th century. Richard Trevithick ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oscillating Cylinder Steam Engine
An oscillating cylinder steam engine (also known as a wobbler in the US) is a simple steam-engine design (proposed by William Murdoch at the end of 18th century) that requires no valve gear. Instead the cylinder rocks, or oscillates, as the crank moves the piston, pivoting in the mounting trunnion so that ports in the cylinder line up with ports in a fixed port face alternately to direct steam into or out of the cylinder. Oscillating cylinder steam engines are now mainly used in toys and models but, in the past, have been used in full-size working engines, mainly on ships and small stationary engines. They have the advantage of simplicity and, therefore, low manufacturing costs. They also tend to be more compact than other types of cylinder of the same capacity, which makes them advantageous for use in ships. Operation alt=oscillating cylinder diagram, Operation of a simple oscillating cylinder steam engine The steam needs to be fed into the end of the cylinder at just the rig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Diesel Engine
Marine propulsion is the mechanism or system used to generate thrust to move a watercraft through water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electric motor or internal combustion engine driving a propeller, or less frequently, in pump-jets, an impeller. Marine engineering is the discipline concerned with the engineering design process of marine propulsion systems. Human-powered paddles and oars, and later, sails were the first forms of marine propulsion. Rowed galleys, some equipped with sail, played an important early role in early human seafaring and warfares. The first advanced mechanical means of marine propulsion was the marine steam engine, introduced in the early 19th century. During the 20th century it was replaced by two-stroke or four-stroke diesel engines, outboard motors, and gas turbine engines on faster ships. Marine nuclear reactors, which appeared in the 1950s, pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gudgeon Pin
In internal combustion engines, the gudgeon pin (UK, wrist pin or piston pin US) connects the piston to the connecting rod, and provides a bearing for the connecting rod to pivot upon as the piston moves.Nunney, Malcolm James (2007) "The Reciprocating Piston Petrol Engine: Gudgeon pins and their location" ''Light and heavy vehicle technology'' (4th ed.) Butterworth-Heinemann, Oxford, UKp. 28 In very early engine designs, including those driven by steam, and many very large stationary or marine engines, the gudgeon pin is located in a sliding crosshead that connects to the piston via a rod. A gudgeon is a pivot or journal. The origin of the word gudgeon is the Middle English word gojoun, which originated from the Middle French word goujon. Its first known use was in the 15th century.Webster's Seventh New Collegiate Dictionary, G & C Merriam Company, 1963, p. 370 Overview The gudgeon pin is typically a forged short hollow rod made of a steel alloy of high strength and hardness tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crosshead Guide
In mechanical engineering, a crosshead is a mechanical joint used as part of the slider-crank linkages of long reciprocating engines (either internal combustion or steam) and reciprocating compressors to eliminate sideways force on the piston. Also, the crosshead enables the connecting rod to freely move outside the cylinder. Because of the very small bore-to-stroke ratio on such engines, the connecting rod would hit the cylinder walls and block the engine from rotating if the piston was attached directly to the connecting rod like on trunk engines. Therefore, the longitudinal dimension of the crosshead must be matched to the stroke of the engine. Overview On smaller engines, the connecting rod links the piston and the crankshaft directly, but this transmits sideways forces to the piston, since the crankpin (and thus the direction the force is applied) moves from side to side with the rotary motion of the crank. These transverse forces are tolerable in a smaller engine. A large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
