Roller chain: Difference between revisions

[[Image:The sketch (drawing) of roller chain, Leonardo da Vinci.jpg|thumb|250px|The [[sketch (drawing)|sketch]] of roller chain, [[Leonardo da Vinci]], [[Codex Atlanticus]]]]

'''Roller chain''' or '''bush roller chain''' is the type of [[chain drive]] most commonly used for transmission of [[power transmission#Mechanical power|mechanical power]] on many kinds of domestic, [[Industrial sector|industrial]] and agricultural machinery, including [[conveyor]]s, [[wire]]- and [[tube (fluid conveyance)|tube]]-[[drawing (manufacturing)|drawing]] machines, [[printing press]]es, [[car]]s, [[motorcycle]]s, and [[bicycle]]s. It consists of a series of short cylindrical rollers held together by side links. It is driven by a toothed wheel called a [[sprocket]]. It is a simple,<ref>[[Template:Citation needed]]</ref> reliable, and efficient<ref name="hw.ac.uk">As much as 98% efficient under ideal conditions, according to {{cite web | last = Kidd | first = Matt D. |author2=N. E. Loch |author3=R. L. Reuben | year = 1998 | url = http://www.hw.ac.uk/mecWWW/research/mdk/res.htm | title = Bicycle Chain Efficiency | work = The Engineering of Sport conference | publisher = Heriot-Watt University | access-date = 16 May 2006 |archive-url = https://web.archive.org/web/20060206210227/http://www.hw.ac.uk/mecWWW/research/mdk/res.htm <!-- Bot retrieved archive --> |archive-date = 6 February 2006}}</ref> means of power transmission.

Sketches by [[Leonardo da Vinci]] in the 16th century show a chain with a [[rolling-element bearing#Roller bearings|roller bearing]].<ref> In the 16th century, [[Leonardo da Vinci]] made sketches of what appears to be the first steel chain. These chains were probably designed to transmit pulling, not wrapping, power because they consist only of plates and pins and have metal fittings. However, da Vinci's sketch does show a roller bearing.{{cite book | title=The Complete Guide to Chain | editor=Tsubakimoto Chain Co. | editor-link=Tsubakimoto Chain Co. | publisher=Kogyo Chosaki Publishing Co., Ltd. | isbn=0-9658932-0-0 | year=1997 | pages=240 | id=p. 211 | url=http://chain-guide.com/breaks/brief-history-of-chain.html | access-date = 17 May 2006}}</ref> In 1800, [[James Fussell IV|James Fussell]] patented a roller chain on development of his [[balance lock]]<ref name="Fussell patent">{{cite web |title=The Repertory of Patent Inventions, and Other Discoveries and Improvements in Arts, Manufactures, and Agriculture: Being a Continuation, on an Enlarged Plan, of the Repertory of Arts and Manufactures ... |url=https://wwwbooks.google.co.ukcom/books/edition/The_Repertory_of_Patent_Inventions_and_O/?id=aSY1AAAAMAAJ |publisher=G. and T. Wilkie |access-date=7 January 2021 |page=303 |language=en |date=1800}}</ref> and in 1880 [[Hans Renold]] patented a bush roller chain.<ref name="Reid 2015 196">{{cite book |last1=Reid |first1=Carlton |title=Roads were not built for cars : How cyclists were the first to push for good roads & became the pioneers of motoring |date=2015 |publisher=Island Press |location=Washington, DC |isbn=9781610916899 |page=196 }}</ref>

The roller chain design reduces friction compared to simpler designs, resulting in higher efficiency and less wear. The original power transmission chain varieties lacked rollers and bushings, with both the inner and outer plates held by pins which directly contacted the [[sprocket]] teeth; however this configuration exhibited extremely rapid wear of both the sprocket teeth, and the plates where they pivoted on the pins. This problem was partially solved by the development of bushed chains, with the pins holding the outer plates passing through bushings or sleeves connecting the inner plates. This distributed the wear over a greater area; however the teeth of the sprockets still wore more rapidly than is desirable, from the sliding friction against the bushings. The addition of rollers surrounding the bushing sleeves of the chain and provided rolling contact with the teeth of the sprockets resulting in excellent resistance to wear of both sprockets and chain as well. There is even very low friction, as long as the chain is sufficiently lubricated. Continuous, clean, lubrication of roller chains is of primary importance for efficient operation, as well asis correct tensioning.<ref>{{Cite web|title=Chain Lubrication Best Practices for Drives and Conveyors|url=https://www.machinerylubrication.com/Read/316/chains-drives-lubricants|access-date=2021-11-24|website=www.machinerylubrication.com|language=en}}</ref>

There are also many chains that have to operate in dirty conditions, and for size or operational reasons cannot be sealed. Examples include chains on [[list of agricultural machinery|farm equipment]], bicycles, and [[chain saw]]s. These chains will necessarily have relatively high rates of wear, particularly when the operators are prepared to accept more friction, less efficiency, more noise and more frequent replacement as they neglect lubrication and adjustment.

Many oil-based lubricants attract dirt and other particles, eventually forming an abrasive paste that will compound wear on chains. This problem can be circumventedreduced by use of a "dry" [[Polytetrafluoroethylene|PTFE]] spray, which forms a solid film after application and repels both particles and moisture.<ref>{{Cite news|url=https://interflonusa.com/what-is-micpol/#assembly|title=What is MicPol?|work=Lubrication|access-date=2018-10-03|language=en|archive-date=3 October 2018|archive-url=https://web.archive.org/web/20181003141443/https://interflonusa.com/what-is-micpol/#assembly|url-status=dead}}</ref>

==Variants in design==

Roller chain is made in several sizes, the most common [[American National Standards Institute]] (ANSI) standards being 40, 50, 60, and 80. The first digit(s)digits indicate the pitch of the chain in eighths of an [[inch]], with the last digit being 0 for standard chain, 1 for lightweight chain, and 5 for bushed chain with no rollers. Thus, a chain with half-inch pitch would beis a #No. 40 while a #No. 160 sprocket would havehas teeth spaced 2&nbsp;inches apart, etc. Metric pitches are expressed in sixteenths of an inch; thus a metric #No. 8 chain (08B-1) would beis equivalent to an ANSI #No. 40. Most roller chain is made from plain carbon or alloy steel, but stainless steel is used in food processing machinery or other places where lubrication is a problem, and nylon or brass are occasionally seen for the same reason.

Roller chain is ordinarily hooked up using a master link (also known as a "connecting link"), which typically has one pin held by a [[horseshoe clip]] rather than friction fit, allowing it to be inserted or removed with simple tools. Chain with a removable link or pin is also known as "cottered chain", which allows the length of the chain to be adjusted. Half links (also known as "offsets") are available and are used to increase the length of the chain by a single roller. Riveted roller chain has the master link (also known as a "connecting link") "riveted" or mashed on the ends. These pins are made to be durable and are not removable.<ref>{{cite web|url=http://panzit.com/library/chain/riveted-vs-cottered-chain/|title=Riveted vs Cottered Chain - Panzit Library|work=panzit.com|access-date=17 January 2015|archive-url=https://web.archive.org/web/20120426080753/http://panzit.com/library/chain/riveted-vs-cottered-chain/|archive-date=26 April 2012}}</ref>

A '''Horseshoehorseshoe clip''' is the U-shaped spring steel fitting that holds the side-plate of the joining (or "master") link formerly essential to complete the loop of a roller chain. The clip method is losing popularity as more and more chains are manufactured as endless loops not intended for maintenance. Modern motorcycles are often fitted with an endless chain but in the increasingly rare circumstances of the chain wearing out and needing to be replaced, a length of chain and a joining link (with horseshoe clip) will be provided as a spare. Changes in motorcycle suspension are tending to make this use less prevalent.

* Roller chains are used in low- to mid-speed drives at around 600 to 800 feet per minute; however, at higher speeds, around 2,000 to 3,000 feet per minute, [[belt Belt_(mechanical)#V_belts|V-belt]]s are normally used due to wear and noise issues.

* The great majority ofSome [[automobile]] [[engine]]s use roller chains to drive the [[camshaft]](s). Very high performance engines often use gear drive, and starting in the early 1960s [[toothed belt]]s were used by some manufacturers.

*A perhaps unusual use of a pair of motorcycle chains is in the [[Harrier Jumpjump Jetjet]], where a chain drive from an air motor is used to rotate the movable engine nozzles, allowing them to be pointed downwards for hovering flight, or to the rear for normal forward flight, a system known as "[[Thrustthrust vectoring]]".

Chain failure is much less of a problem on hub-geared systems (e.g.since Bendixthe 2-speed,chainline Sturmey-Archerdoes AW)not sincebend, so the parallel pins have a much bigger wearing surface in contact with the bush. The hub-gear system also allows complete enclosure, a great aid to lubrication and protection from grit.

[[Standards organization]]s (such as [[ANSI]] and [https://www.iso.org/committee/50982/x/catalogue/ ISO]) maintain standards for design, dimensions, and [[interchangeable parts|interchangeability]] of transmission chains. For example, the following Tabletable shows data from ANSI standard B29.1-2011 (Precisionprecision Powerpower Transmissiontransmission Rollerroller Chainschains, Attachmentsattachments, and Sprocketssprockets)<ref name="ASME B29.1-2011">[https://www.asme.org/products/codes-standards/b291-2011-precision-power-transmission-roller ASME B29.1-2011 - Precision Power Transmission Roller Chains, Attachments, and Sprockets].</ref> developed by the [[American Society of Mechanical Engineers]] (ASME). See the references<ref>{{cite book | title=The Complete Guide to Chain | editor=Tsubakimoto Chain Co. | editor-link=Tsubakimoto Chain Co. | publisher=Kogyo Chosaki Publishing Co., Ltd. | isbn=0-9658932-0-0 | year=1997 | pages=240 | id=p. 86 | url=http://chain-guide.com/applications/1-1-1-ansi-roller-chains.html | access-date = 30 January 2015 | chapter=Transmission Chains | chapter-url=http://chain-guide.com/applications/1-transmission-chains.html }}</ref><ref name="MachinerysHandbook25epp2337-2361">{{Harvnb|GreenMachinery's Handbook|1996|pp=2337–2361}}</ref><ref>{{cite web |title=ANSI G7 Standard Roller Chain - Tsubaki Europe |url=http://tsubaki.eu/chain/ansi-standard-roller-chain/#Single |work=Tsubaki Europe |publisher=Tsubakimoto Europe B.V. |access-date=18 June 2009}}</ref> for additional information.

|colspan="8" |ASME/ANSI B29.1-2011 Roller Chainchain Standardstandard Sizessizes

!Maximum Rollerroller Diameterdiameter

!Minimum Ultimateultimate Tensiletensile Strengthstrength

!Measuring Loadload

| colspan="4" | Notes:<br /> 1. *The pitch is the distance between roller centers. The width is the distance between the link plates (i.e. slightly more than the roller width to allow for clearance).<br /> 2. *The right-hand digit of the standard denotes 0 = normal chain, 1 = lightweight chain, 5 = rollerless bushing chain. <br /> 3. *The left-hand digit denotes the number of eighths of an inch that make up the pitch. <br /> 4. *An "H" following the standard number denotes heavyweight chain. A hyphenated number following the standard number denotes double-strand (2), triple-strand (3), and so on. Thus 60H-3 denotes 3/4 inch pitch heavyweight triple-strand chain.

A typical bicycle chain (for [[derailleur gears]]) uses narrow {{frac|1|2}}-inch-pitch chain. The width of the chain is variable, and does not affect the load capacity. The more sprockets at the rear wheel (historically 3–6, nowadays 7–12 sprockets), the narrower the chain. Chains are sold according to the number of speeds they are designed to work with, for example, "10 speed chain". Hub gear or single speed bicycles use 1/2" x 1/8" inch chains, where 1/8" inch refers to the maximum thickness of a sprocket that can be used with the chain.

Roller chains made using ISO standard are sometimes called as "isochains".

{{Commons category|Roller chains}}https://www.leonardodigitale.com/en/browse/Codex-atlanticus/0987-r/