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| {{About|machinery and engineering|the rock band|Moving Parts|the musical album|Fewer Moving Parts}}
| | I would like to introduce myself to you, I am Andrew and my wife doesn't like it at all. One of the issues she enjoys most is canoeing and she's been doing it for quite a while. Distributing production is how he tends to make a living. My spouse and I live in Kentucky.<br><br>my web page psychic readings online, [http://myoceancounty.net/groups/apply-these-guidelines-when-gardening-and-grow/ click], |
| [[File:Engine movingparts.jpg|thumb|right|some of the moving parts of an automobile engine]]
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| The '''moving parts''' of a [[machine]] are those parts of it that move. Machines include both moving (or movable) and fixed parts. The moving parts have controlled and constrained motions.<ref name=Bhandari2001 /><ref name=Goodeve1860 />
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| Moving parts do not include any moving fluids, such as [[fuel]], [[coolant]] or [[hydraulic fluid]].{{Citation needed|date=July 2010}} Moving parts also do not include any mechanical [[lock (device)|lock]]s, [[switch]]es, [[Nut (hardware)|nuts]] and [[Screw|bolts]], [[screw cap]]s for bottles etc. A system with no moving parts is described as "[[Solid-state (electronics)|solid state]]".
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| == Mechanical efficiency and wear ==
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| The amount of moving parts in a machine is a factor in its [[mechanical efficiency]]. The greater the number of moving parts, the greater the amount of energy lost to heat by [[friction]] between those parts.<ref name=Balmer2008 /> In a modern [[automobile engine]], for example, roughly 7% of the total [[Power (physics)|power]] obtained from burning the engine's fuel is lost to friction between the engine's moving parts.<ref name=Moeller2002 />
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| Conversely, the fewer the number of moving parts, the greater the efficiency. Machines with no moving parts at all can be very efficient. An [[electrical transformer]], for example, has no moving parts, and its mechanical efficiency is generally above the 90% mark. (The remaining power losses in a transformer are from other causes, including loss to electrical resistance in the copper windings and [[hysteresis]] loss and [[eddy current]] loss in the iron core.)<ref name=Linsley2008 />
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| Two means are used for overcoming the efficiency losses caused by friction between moving parts. First, moving parts are [[lubrication|lubricated]]. Second, the moving parts of a machine are designed so that they have a small amount of contact with one another. The latter, in its turn, comprises two approaches. A machine can be reduced in size, thereby quite simply reducing the areas of the moving parts that rub against one another; and the designs of the individual components can be modified, changing their shapes and structures to reduce or avoid contact with one another.<ref name=Moeller2002 />
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| Lubrication also reduces [[wear]], as does the use of suitable materials. As moving parts wear out, this can affect the precision of the machine. Designers thus have to design moving parts with this factor in mind, ensuring that if precision over the lifetime of the machine is paramount, that wear is accounted for and, if possible, minimized. (A simple example of this is the design of a simple single-wheel [[wheelbarrow]]. A design where the [[axle]] is fixed to the barrow arms and the wheel rotates around it is prone to wear which quickly causes wobble, whereas a rotating axle that is attached to the wheel and that rotates upon [[bearing (mechanical)|bearing]]s in the arms does not start to wobble as the axle wears through the arms.)<ref name=Wilson1952 />
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| The scientific and engineering discipline that deals with the lubrication, friction, and wear of moving parts is [[tribology]], an interdisciplinary field that encompasses [[materials science]], [[mechanical engineering]], [[chemistry]], and [[mechanics]].<ref name=Wakelin1974 />
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| == Failure ==
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| As mentioned, wear is a concern for moving parts in a machine.<ref name=Todinov2007 /> Other concerns that lead to failure include [[corrosion]],<ref name=Todinov2007 /> [[erosion]],<ref name=Todinov2007 /> [[thermal stress]] and heat generation,<ref name=Todinov2007 /> [[vibration]],<ref name=Todinov2007 /> [[fatigue loading]],<ref name=Todinov2007 /> and [[cavitation]].
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| Fatigue is related to large inertial forces, and is affected by the type of motion that a moving part has. A moving part that has a uniform rotation motion is subject to less fatigue than a moving part that oscillates back and forth. Vibration leads to failure when the ''forcing frequency'' of the machine's operation hits a [[resonant frequency]] of one or more moving parts, such as rotating shafts. Designers avoid this by calculating the natural frequencies of the parts at design time, and altering the parts to limit or eliminate such resonance.
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| Yet further factors that can lead to failure of moving parts include failures in the cooling and lubrication systems of a machine.<ref name="Todinov2007" />
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| One final, particular, factor related to failure of moving parts is kinetic energy. The sudden release of the kinetic energy of the moving parts of a machine causes overstress failures if a moving part is impeded in its motion by a foreign object, such as stone caught on the blades of a fan or propellor, or even the proverbial "[[Wrench|spanner]]/[[monkey wrench]] in the works".<ref name=Todinov2007 /> (See [[foreign object damage]] for further discussion of this.)
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| == Kinetic energy of the moving parts of a machine ==
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| The [[kinetic energy]] of a machine is the sum of the kinetic energies of its individual moving parts. A machine with moving parts can, mathematically, be treated as a connected system of bodies, whose kinetic energies are simply summed. The individual kinetic energies are determined from the kinetic energies of the moving parts' [[translation (physics)|translation]]s and [[rotation]]s about their axes.<ref name=Hibbeler2009 />
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| The ''kinetic energy of rotation of the moving parts'' can be determined by noting that every such system of moving parts can be reduced to a collection of connected bodies rotating about an instantaneous axis, which form either a ring or a portion of an ideal ring, of radius <math>a</math> rotating at <math>n</math> [[revolutions per minute|revolutions per second]]. This ideal ring is known as the ''equivalent flywheel'', whose radius is the ''radius of gyration''. The [[integral]] of the squares of the radii all the portions of the ring with respect to their mass <math>\int a^2 dm</math>, also expressible if the ring is modelled as a collection of discrete particles as the sum of the products of those mass and the squares of their radii <math>\sum_{k=0}^n m_k \times a_k^2</math> is the ring's [[moment of inertia]], denoted <math>I</math>. The rotational kinetic energy of the whole system of moving parts is <math>\frac{1}{2} I \omega^2</math>, where <math>\omega</math> is the [[angular velocity]] of the moving parts about the same axis as the moment of inertia.<ref name=Hibbeler2009 /><ref name=Cotterill1884 />
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| The ''kinetic energy of translation'' of the moving parts is <math>\frac{1}{2} m v^2</math>, where <math>m</math> is the total mass and <math>v</math> is the [[Magnitude (vector)|magnitude]] of the [[velocity]]. This gives the formula for the ''total kinetic energy of the moving parts of a machine'' as <math>\frac{1}{2} I \omega^2 + \frac{1}{2} m v^2</math>.<ref name=Hibbeler2009 /><ref name=Cotterill1884 />
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| == Representing moving parts in engineering diagrams ==
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| [[File:Exemple lineaire rectiligne et glissiere iso et hyperstatique .svg|thumb|file|This engineering diagram (illustrating the principle in [[kinematic design]] that using incorrect types/numbers of mechanical linkages can cause fixed parts to wobble<ref name=Wilson1952 />) shows the motion of the wobbling parts with a solid outline of the moving part in one position at one extremity of its motion and a phantom line outline of the part in the position at the other extremity.]]
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| In [[technical drawing]], moving parts are, conventionally, designated by drawing the solid outline of the part in its main or initial position, with an added outline of the part in a secondary, moved, position drawn with a ''phantom line'' (a line comprising "dot-dot-dash" sequences of two short and one long line segments) outline.<ref name=LoPressman2007 /><ref name=Madsen2001 /><ref name=JensenHelsel1985 /> These conventions are enshrined in several standards from the [[American National Standards Institute]] and the [[American Society of Mechanical Engineers]], including ASME Y14.2M published in 1979.<ref name=Wright2002 />
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| In recent decades, the use of [[animation]] has become more practical and widespread in technical and engineering diagrams for the illustration of the motions of moving parts. Animation represents moving parts more clearly and enables them and their motions to be more readily visualized.<ref name=GoetschChalkNelson1999 /> Furthermore, [[computer aided design]] tools allow the motions of moving parts to be simulated, allowing machine designers to determine, for example, whether the moving parts in a given design would obstruct one another's motion or collide by simple visual inspection of the (animated) computer model rather than by the designer performing a numerical analysis directly.<ref name=Comninos1989 /><ref name=Steadman1989 />
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| == See also ==
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| * [[kinetic art]] — sculpture that contains moving parts
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| * [[movement (clockwork)]] — the specific name for the moving parts of a clock or watch
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| == References ==
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| <references>
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| <ref name=Balmer2008>{{cite book|title=Doc Fizzix Mousetrap Racers: The Complete Builder's Manual|author=Alden J. Balmer|publisher=Fox Chapel Publishing|year=2008|isbn=9781565233591|pages=32}}</ref>
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| <ref name=Hibbeler2009>{{cite book|title=Engineering Mechanics: Dynamics|author=Russell C. Hibbeler|edition=12th|publisher=Prentice Hall|year=2009|isbn=9780136077916|pages=457–458}}</ref>
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| <ref name=Cotterill1884>{{cite book|title=Applied Mechanics. An Elementary General Introduction to the Theory of Structures and Machines. With Diagrams, Illustrations, and Examples|author=James Henry Cotterill|edition=Adegi Graphics LLC reprint|isbn=9781421257013|pages=212–215|year=1884|publisher=Macmillan & Co.|location=London}}</ref>
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| <ref name=Moeller2002>{{cite book|title=Energy efficiency: issues and trends|author=Steven T. Moeller|publisher=Nova Publishers|year=2002|isbn=9781590332016|pages=57}}</ref>
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| <ref name=Linsley2008>{{cite book|title=Advanced Electrical Installation Work|author=Trevor Linsley|edition=5th|publisher=Newnes|year=2008|isbn=9780750687522|pages=216}}</ref>
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| <ref name=LoPressman2007>{{cite book|title=How to Make Patent Drawings: A Patent It Yourself Companion|author=Jack Lo and David Pressman|edition=5th|publisher=Nolo|year=2007|isbn=9781413306538|pages=226}}</ref>
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| <ref name=Madsen2001>{{cite book|title=Engineering drawing and design|series=Delmar drafting series|author=David A. Madsen|edition=3rd|publisher=Cengage Learning|year=2001|pages=48|isbn=9780766816343}}</ref>
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| <ref name=JensenHelsel1985>{{cite book|title=Fundamentals of engineering drawing|author=Cecil Howard Jensen and Jay D. Helsel|edition=2nd|publisher=Gregg Division, McGraw-Hill|year=1985|isbn=9780070325340|pages=28}}</ref>
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| <ref name=Wright2002>{{cite book|title=Introduction to engineering|series=Wiley Desktop Editions Series|author=Paul H. Wright|edition=3rd|publisher=John Wiley and Sons|year=2002|isbn=9780471059202|pages=155–156,171}}</ref>
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| <ref name=Bhandari2001>{{cite book|title=Introduction to machine design|author=V B Bhandari|publisher=Tata McGraw-Hill|year=2001|isbn=9780070434493|pages=1}}</ref>
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| <ref name=Goodeve1860>{{cite book|title=The Elements of Mechanism|author=Thomas Minchin Goodeve|edition=Read Books 2007 reprint|isbn=9781406700497|pages=1|location=London|publisher=Longman, Green, Longman, and Roberts}}</ref>
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| <ref name=GoetschChalkNelson1999>{{cite book|title=Technical drawing|series=Delmar technical graphics series|author=David L. Goetsch, William Chalk, John A. Nelson|edition=4th|publisher=Cengage Learning|year=1999|isbn=9780766805316|pages=452, 456}}</ref>
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| <ref name=Wilson1952>{{cite book|title=An introduction to scientific research|series=Dover books explaining science|author=Edgar Bright Wilson|publisher=Courier Dover Publications|edition=1991 reprint|year=1952|isbn=9780486665450|pages=104–105,108}}</ref>
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| <ref name=Wakelin1974>{{cite book|title=Annual review of materials science|volume=4|editor=Robert A. Huggins|publisher=Annual Reviews, inc.|year=1974|isbn=9780824317041|pages=221|chapter=Tribology: The Friction, Lubrication, and Wear of Moving Parts|author=R. J. Wakelin}}</ref>
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| <ref name=Comninos1989>{{cite book|title=Computers in art, design, and animation|editor=John Lansdown and Rae A. Earnshaw|author=Peter P. Comninos|chapter=Computer Graphics and Animation for Interior and Industrial Designers|publisher=Springer|year=1989|isbn=9780387968964|pages=216–217}}</ref>
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| <ref name=Steadman1989>{{cite book|title=Computers in art, design, and animation|editor=John Lansdown and Rae A. Earnshaw|author=Philip Steadman|chapter=Computer Assistance to the Design Process|publisher=Springer|year=1989|isbn=9780387968964|pages=158}}</ref>
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| <ref name=Todinov2007>{{cite book|title=Risk-based reliability analysis and generic principles for risk reduction|author=M. T. Todinov|publisher=Elsevier|year=2007|isbn=9780080447285|pages=208–209}}</ref>
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| </references>
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| == Further reading ==
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| * {{cite journal|publisher=[[American National Standards Institute]]|title=Line conventions and lettering|id=ANSI/ASME Y14.2M|location=New York|year=1979}}
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| * {{cite journal|title=Method of diagramming for moving parts fluid controls|id=ANSI/NFPA T3.28.9-1976|publisher=[[National Fluid Power Association]] and [[American National Standards Institute]]|year=1976}}
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| [[Category:Technology]]
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| [[Category:Machinery]]
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I would like to introduce myself to you, I am Andrew and my wife doesn't like it at all. One of the issues she enjoys most is canoeing and she's been doing it for quite a while. Distributing production is how he tends to make a living. My spouse and I live in Kentucky.
my web page psychic readings online, click,