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China manufacturer Heavy Duty Series Duplex Industrial Agricultural Transmission Conveyor Roller Chains with Standard America European ANSI or Made to Drawing wholesaler

Merchandise Description

Weighty Duty Collection Duplex Roller Chains & Bush Chains

ISO/ANSI
Chain No.
 
Pitch

P
mm
 

Roller diameter

d1max
mm
 

Width in between inner plates
b1min
mm
 
Pin diameter

d2max
mm
 

Pin size Inner plate depth
h2max
mm
 
Plate thickness

Tmax
mm
 

Transverse pitch
Pt
mm
 
Tensile strength

Qmin
kN/lbf
 

Average tensile toughness
Q0
kN
 
Weight for every meter
q kg/m
 
Lmax
mm
Lcmax
mm
60H-two 19.050 eleven.ninety one twelve.57 5.ninety four fifty five.3 57.1 eighteen.00 3.twenty five 26.11 sixty three.6/14455 eighty four.five 3.71
80H-two twenty five.four hundred 15.88 15.seventy five 7.ninety two sixty eight.8 70.3 24.00 four.00 32.fifty nine 113.4/25773 145.three 6.15
100H-two 31.750 19.05 eighteen.90 9.fifty three eighty two.seven 86. 30.00 four.eighty 39.09 177./45717 225.nine 9.03
120H-two 38.a hundred 22.23 25.22 11.ten 102.four 106.four 35.70 5.sixty forty eight.87 254./57727 322.7 13.13
140H-two forty four.450 25.forty 25.22 12.70 109.8 114.four 41.00 6.forty 52.20 344.8/78364 437.seven 16.sixty
160H-two fifty.800 28.58 31.55 fourteen.27 one hundred thirty.one 134.nine forty seven.80 7.twenty sixty one.ninety 453.6/103091 571.six 20.twenty
180H-two 57.one hundred fifty 35.seventy one 35.forty eight seventeen.forty six 146.5 a hundred and fifty five.6 53.sixty 8.00 sixty nine.sixteen 562/127726 680. 29.20
200H-2 sixty three.500 39.sixty eight 37.eighty five 19.eighty five 164.nine 171.eight 60.00 nine.fifty 78.31 707.6/sixteen 0571 894.9 38.11
240H-2 76.200 47.sixty three 47.35 23.eighty one 212.six 223.1 seventy two.30 twelve.70 one zero one.22 a thousand/227270 1200. 60.fifty

 

ROLLER CHAIN

Roller chain or bush roller chain is the sort of chain drive most typically used for transmission of mechanical energy on several varieties of domestic, industrial and agricultural machinery, including conveyors, wire- and tube-drawing devices, printing presses, automobiles, bikes, and bicycles. It is composed of a series of brief cylindrical rollers held with each other by facet backlinks. It is driven by a toothed wheel named a sprocket. It is a simple, reputable, and productive signifies of electrical power transmission.

Construction OF THE CHAIN

Two distinct sizes of roller chain, displaying construction.
There are 2 sorts of hyperlinks alternating in the bush roller chain. The 1st sort is internal hyperlinks, possessing 2 inner plates held with each other by 2 sleeves or bushings upon which rotate 2 rollers. Interior hyperlinks alternate with the second kind, the outer back links, consisting of 2 outer plates held with each other by pins passing by way of the bushings of the inner hyperlinks. The “bushingless” roller chain is related in procedure however not in building alternatively of different bushings or sleeves holding the interior plates collectively, the plate has a tube stamped into it protruding from the gap which serves the very same purpose. This has the advantage of eliminating 1 stage in assembly of the chain.

The roller chain style reduces friction in contrast to easier designs, resulting in larger performance and much less use. The first power transmission chain types lacked rollers and bushings, with each the inner and outer plates held by pins which directly contacted the sprocket tooth however this configuration exhibited really fast use of equally the sprocket enamel, and the plates exactly where they pivoted on the pins. This dilemma was partly solved by the advancement of bushed chains, with the pins keeping the outer plates passing through bushings or sleeves connecting the inner plates. This distributed the put on over a greater area however the tooth of the sprockets nonetheless wore far more swiftly than is appealing, from the sliding friction from the bushings. The addition of rollers bordering the bushing sleeves of the chain and presented rolling get in touch with with the tooth of the sprockets ensuing in exceptional resistance to wear of each sprockets and chain as well. There is even quite lower friction, as lengthy as the chain is sufficiently lubricated. Ongoing, cleanse, lubrication of roller chains is of primary significance for productive procedure as properly as correct tensioning.

LUBRICATION

Numerous driving chains (for instance, in manufacturing facility tools, or driving a camshaft within an inner combustion engine) function in clear environments, and hence the wearing surfaces (that is, the pins and bushings) are safe from precipitation and airborne grit, numerous even in a sealed environment such as an oil tub. Some roller chains are developed to have o-rings constructed into the space among the exterior hyperlink plate and the inside roller website link plates. Chain manufacturers started to incorporate this characteristic in 1971 right after the software was invented by Joseph Montano although functioning for Whitney Chain of Hartford, Connecticut. O-rings were integrated as a way to boost lubrication to the hyperlinks of electricity transmission chains, a service that is vitally important to extending their functioning existence. These rubber fixtures form a barrier that holds manufacturing facility utilized lubricating grease inside of the pin and bushing put on places. Additional, the rubber o-rings avoid dirt and other contaminants from getting into inside the chain linkages, in which these kinds of particles would or else result in significant use.[citation necessary]

There are also a lot of chains that have to function in soiled situations, and for measurement or operational motives can not be sealed. Illustrations consist of chains on farm equipment, bicycles, and chain saws. These chains will necessarily have relatively large prices of put on, specifically when the operators are geared up to take more friction, considerably less efficiency, far more sounds and much more regular replacement as they neglect lubrication and adjustment.

Many oil-dependent lubricants entice dirt and other particles, sooner or later forming an CZPT paste that will compound wear on chains. This issue can be circumvented by use of a “dry” PTFE spray, which varieties a solid film soon after application and repels both particles and moisture.

VARIANTS Design and style

Layout of a roller chain: 1. Outer plate, 2. Internal plate, 3. Pin, 4. Bushing, 5. Roller
If the chain is not becoming utilized for a high use software (for occasion if it is just transmitting motion from a hand-operated lever to a control shaft on a machine, or a sliding doorway on an oven), then 1 of the easier types of chain may nonetheless be utilised. Conversely, in which added energy but the clean push of a smaller pitch is essential, the chain could be “siamesed” rather of just 2 rows of plates on the outer sides of the chain, there may be 3 (“duplex”), 4 (“triplex”), or much more rows of plates managing parallel, with bushings and rollers amongst each and every adjacent pair, and the very same quantity of rows of teeth managing in parallel on the sprockets to match. Timing chains on automotive engines, for case in point, generally have a number of rows of plates called strands.

Roller chain is made in a number of sizes, the most frequent American Countrywide Requirements Institute (ANSI) specifications being forty, 50, sixty, and 80. The very first digit(s) indicate the pitch of the chain in eighths of an inch, with the last digit becoming 0 for common chain, 1 for lightweight chain, and 5 for bushed chain with no rollers. As a result, a chain with fifty percent-inch pitch would be a #40 whilst a #a hundred and sixty sprocket would have tooth spaced 2 inches apart, and so forth. Metric pitches are expressed in sixteenths of an inch hence a metric #8 chain (08B-1) would be equal to an ANSI #forty. Most roller chain is produced from plain carbon or alloy metal, but stainless metal is utilised in foods processing machinery or other places the place lubrication is a problem, and nylon or brass are sometimes noticed for the very same reason.

Roller chain is ordinarily hooked up utilizing a master link (also known as a connecting url), which normally has 1 pin held by a horseshoe clip relatively than friction in shape, making it possible for it to be inserted or removed with basic tools. Chain with a removable hyperlink or pin is also identified as cottered chain, which permits the length of the chain to be adjusted. Fifty percent back links (also recognized as offsets) are offered and are utilized to improve the length of the chain by a single roller. Riveted roller chain has the master url (also acknowledged as a connecting link) “riveted” or mashed on the ends. These pins are made to be durable and are not removable.

USE

An illustration of 2 ‘ghost’ sprockets tensioning a triplex roller chain method
Roller chains are employed in reduced- to mid-velocity drives at all around 600 to 800 ft for every moment nonetheless, at increased speeds, close to 2,000 to 3,000 feet for each moment, V-belts are usually utilised thanks to use and sounds troubles.
A bicycle chain is a form of roller chain. Bicycle chains might have a master website link, or could require a chain instrument for removing and installation. A similar but bigger and as a result more robust chain is utilized on most motorcycles despite the fact that it is sometimes changed by either a toothed belt or a shaft push, which supply decrease sounds degree and less routine maintenance specifications.
The excellent bulk of automobile engines use roller chains to generate the camshaft(s). Really large functionality engines usually use equipment drive, and starting up in the early sixties toothed belts had been used by some makers.
Chains are also employed in forklifts employing hydraulic rams as a pulley to CZPT and reduce the carriage however, these chains are not considered roller chains, but are categorised as carry or leaf chains.
Chainsaw slicing chains superficially resemble roller chains but are much more closely relevant to leaf chains. They are pushed by projecting travel links which also provide to find the chain on to the bar.

Sea Harrier FA.2 ZA195 entrance (cold) vector thrust nozzle – the nozzle is rotated by a chain drive from an air motor
A possibly uncommon use of a pair of motorcycle chains is in the Harrier Jump Jet, in which a chain drive from an air motor is used to rotate the movable engine nozzles, permitting them to be pointed downwards for hovering flight, or to the rear for typical forward flight, a system known as Thrust vectoring.

Dress in

 

The impact of wear on a roller chain is to improve the pitch (spacing of the links), leading to the chain to expand for a longer time. Observe that this is thanks to dress in at the pivoting pins and bushes, not from genuine stretching of the metallic (as does come about to some adaptable steel parts this sort of as the hand-brake cable of a motor automobile).

With CZPT chains it is unusual for a chain (other than that of a bicycle) to use right up until it breaks, given that a worn chain sales opportunities to the speedy onset of wear on the enamel of the sprockets, with greatest failure currently being the reduction of all the teeth on the sprocket. The sprockets (in particular the smaller sized of the two) endure a grinding movement that puts a characteristic hook condition into the pushed confront of the teeth. (This influence is made even worse by a chain improperly tensioned, but is unavoidable no make a difference what treatment is taken). The worn enamel (and chain) no lengthier supplies easy transmission of electrical power and this may possibly turn into apparent from the sounds, the vibration or (in vehicle engines employing a timing chain) the variation in ignition timing witnessed with a timing mild. Both sprockets and chain should be replaced in these circumstances, because a new chain on worn sprockets will not previous prolonged. However, in significantly less extreme circumstances it may possibly be achievable to save the greater of the 2 sprockets, given that it is usually the smaller 1 that suffers the most put on. Only in very gentle-weight apps this kind of as a bicycle, or in severe instances of inappropriate stress, will the chain usually soar off the sprockets.

The lengthening thanks to wear of a chain is calculated by the pursuing method:

M = the size of a number of back links measured

S = the number of backlinks calculated

P = Pitch

In business, it is normal to keep an eye on the motion of the chain tensioner (regardless of whether handbook or automatic) or the exact duration of a drive chain (a single rule of thumb is to exchange a roller chain which has elongated 3% on an adjustable travel or 1.5% on a fixed-centre generate). A simpler method, specifically suitable for the cycle or motorbike user, is to try to pull the chain away from the larger of the 2 sprockets, even though making certain the chain is taut. Any significant movement (e.g. generating it attainable to see by way of a gap) possibly signifies a chain worn up to and outside of the limit. Sprocket harm will end result if the dilemma is disregarded. Sprocket put on cancels this effect, and could mask chain wear.

CHAIN Power

The most widespread measure of roller chain’s toughness is tensile power. Tensile power represents how significantly load a chain can face up to below a one-time load prior to breaking. Just as critical as tensile strength is a chain’s exhaustion power. The crucial elements in a chain’s fatigue power is the good quality of metal utilised to manufacture the chain, the warmth remedy of the chain factors, the good quality of the pitch gap fabrication of the linkplates, and the type of shot additionally the intensity of shot peen protection on the linkplates. Other elements can consist of the thickness of the linkplates and the layout (contour) of the linkplates. The rule of thumb for roller chain working on a continuous push is for the chain load to not CZPT a mere 1/6 or 1/9 of the chain’s tensile energy, depending on the kind of learn hyperlinks utilized (press-suit vs. slip-match)[citation required]. Roller chains working on a continuous travel outside of these thresholds can and typically do are unsuccessful prematurely by means of linkplate exhaustion failure.

The common minimum supreme energy of the ANSI 29.1 steel chain is twelve,five hundred x (pitch, in inches)two. X-ring and O-Ring chains tremendously decrease dress in by signifies of interior lubricants, growing chain lifestyle. The interior lubrication is inserted by indicates of a vacuum when riveting the chain together.

CHAIN STHangZhouRDS

Specifications companies (such as ANSI and ISO) keep requirements for design and style, proportions, and interchangeability of transmission chains. For instance, the following Desk exhibits information from ANSI normal B29.1-2011 (Precision Electricity Transmission Roller Chains, Attachments, and Sprockets) designed by the American Society of Mechanical Engineers (ASME). See the references[8][9][10] for further details.

ASME/ANSI B29.1-2011 Roller Chain Common SizesSizePitchMaximum Roller DiameterMinimum Final Tensile StrengthMeasuring Load25

ASME/ANSI B29.1-2011 Roller Chain Common Measurements
Dimension Pitch Greatest Roller Diameter Bare minimum Final Tensile Strength Measuring Load
twenty five .250 in (6.35 mm) .a hundred thirty in (3.30 mm) 780 lb (350 kg) 18 lb (8.2 kg)
35 .375 in (9.53 mm) .200 in (5.08 mm) 1,760 lb (800 kg) eighteen lb (8.2 kg)
forty one .five hundred in (twelve.70 mm) .306 in (7.77 mm) 1,500 lb (680 kg) 18 lb (8.2 kg)
40 .five hundred in (12.70 mm) .312 in (7.ninety two mm) three,a hundred twenty five lb (1,417 kg) 31 lb (fourteen kg)
fifty .625 in (fifteen.88 mm) .four hundred in (ten.sixteen mm) four,880 lb (2,210 kg) 49 lb (22 kg)
sixty .750 in (19.05 mm) .469 in (11.91 mm) seven,030 lb (3,one hundred ninety kg) 70 lb (32 kg)
80 one.000 in (25.40 mm) .625 in (fifteen.88 mm) twelve,500 lb (5,seven-hundred kg) a hundred twenty five lb (57 kg)
a hundred 1.250 in (31.75 mm) .750 in (19.05 mm) 19,531 lb (8,859 kg) 195 lb (88 kg)
120 one.500 in (38.10 mm) .875 in (22.23 mm) 28,a hundred twenty five lb (twelve,757 kg) 281 lb (127 kg)
one hundred forty one.750 in (forty four.45 mm) 1.000 in (25.forty mm) 38,280 lb (17,360 kg) 383 lb (174 kg)
one hundred sixty 2.000 in (50.eighty mm) 1.125 in (28.58 mm) fifty,000 lb (23,000 kg) five hundred lb (230 kg)
a hundred and eighty 2.250 in (57.fifteen mm) one.460 in (37.08 mm) 63,280 lb (28,seven-hundred kg) 633 lb (287 kg)
200 two.500 in (63.50 mm) 1.562 in (39.67 mm) seventy eight,one hundred seventy five lb (35,460 kg) 781 lb (354 kg)
240 3.000 in (seventy six.20 mm) one.875 in (47.sixty three mm) 112,five hundred lb (51,000 kg) 1,000 lb (450 kg

For mnemonic purposes, under is one more presentation of important proportions from the exact same standard, expressed in fractions of an inch (which was component of the pondering behind the choice of preferred numbers in the ANSI common):

Pitch (inches) Pitch expressed
in eighths
ANSI normal
chain number
Width (inches)
1four 28 twofive 1eight
threeeight three8 three5 threesixteen
onetwo 48 fourone one4
12 four8 4 516
fiveeight five8 five three8
three4 68 six onetwo
one eight8 8 5eight

Notes:
one. The pitch is the distance among roller centers. The width is the length between the url plates (i.e. slightly a lot more than the roller width to enable for clearance).
2. The appropriate-hand digit of the common denotes 0 = normal chain, 1 = light-weight chain, 5 = rollerless bushing chain.
3. The remaining-hand digit denotes the amount of eighths of an inch that make up the pitch.
4. An “H” following the normal amount denotes heavyweight chain. A hyphenated variety pursuing the regular amount denotes double-strand (2), triple-strand (3), and so on. Thus 60H-3 denotes variety 60 heavyweight triple-strand chain.
 A standard bicycle chain (for derailleur gears) uses slim 1⁄2-inch-pitch chain. The width of the chain is variable, and does not affect the load potential. The a lot more sprockets at the rear wheel (traditionally 3-6, today 7-12 sprockets), the narrower the chain. Chains are sold according to the quantity of speeds they are developed to work with, for case in point, “10 pace chain”. Hub gear or one pace bicycles use 1/2″ x 1/8″ chains, in which 1/8″ refers to the greatest thickness of a sprocket that can be used with the chain.

Generally chains with parallel shaped links have an even quantity of back links, with every single narrow website link followed by a broad one. Chains built up with a uniform sort of hyperlink, slender at 1 and broad at the other end, can be produced with an odd quantity of hyperlinks, which can be an edge to adapt to a special chainwheel-distance on the other facet this kind of a chain tends to be not so powerful.

Roller chains made utilizing ISO common are occasionally referred to as as isochains.

 

WHY Select US 

one. Dependable Quality Assurance System
two. Slicing-Edge Pc-Controlled CNC Devices
3. Bespoke Options from Extremely Seasoned Specialists
4. Customization and OEM Offered for Specific Software
5. Extensive Inventory of Spare Areas and Components
6. Well-Produced Worldwide Marketing and advertising Network
7. Successful Following-Sale Services System

 

The 219 sets of superior computerized generation equipment give ensures for high product high quality. The 167 engineers and professionals with senior professional titles can style and build goods to satisfy the exact calls for of buyers, and OEM customizations are also accessible with us. Our audio global service network can supply buyers with well timed soon after-income technical services.

We are not just a producer and supplier, but also an business specialist. We function pro-actively with you to supply expert guidance and solution recommendations in purchase to stop up with a most expense powerful product available for your specific software. The clientele we provide worldwide assortment from finish users to distributors and OEMs. Our OEM replacements can be substituted wherever essential and suited for equally repair and new assemblies.

 

Specialty Chains: A Distinctive Option for Your Particular Undertaking Occasionally Storage of industrial conveyor chains is also important for services daily life. When these components are not in use, they are not able to be positioned at will, or else, the good quality of the chain will be easily ruined. Do not shop these items in humid, substantial temperature and chemically intense places. Keep away from storing in a humid surroundings, since the self-strengthening chain is in a humid surroundings, and the dampness and oxygen masking the surface will chemically react to type rust, hurt the high quality of the chain, and influence sales. Chains should not be placed in locations where the temperature is too large or in direct daylight. Direct sunlight will enhance the temperature of the instant noodles of the chain, which will expand and agreement when heated, thereby shifting the physical qualities of the chain and triggering harm or decline of teeth for the duration of use. Exposing the chain to aggressive chemical substances can severely corrode the sprocket area. Chains generally used in corrosive environments are largely galvanized or nickel-plated chains. For that reason, the chain should be stored in accordance with affordable rules, so as to lengthen the support existence of the chain and reduce the cost of the manufacturer.
a normal roller chain basically is not proper for your task – you are possibly in a difficult surroundings or have weighty-responsibility specifications or demanding programs. While we also supply machining choices for chains and attachments, these “standard” specialty chains are our most well-liked. Do you want nails to the leading of a chain or binding chain? no issue! Our specialist chain merchants are usually at your services. From spires to side bows, each of our specialty chains is built to exacting ANSI requirements, so you can be self-confident your equipment will perform as expected without having unforeseen failures or chain bends.

China manufacturer Heavy Duty Series Duplex Industrial Agricultural Transmission Conveyor Roller Chains with Standard America European ANSI or Made to Drawing     wholesaler

China Professional Heavy Duty Chain Toothen Side Metal Stainless Steel China Series Large Pitch Best Price CZPT Special Attachments Double Sharp to Type Roller Chains near me shop

Merchandise Description

Large Responsibility Chain Toothen Facet Metallic Stainless Steel China Collection Massive Pitch Ideal Price tag Manufacture Special Attachments Double Sharp to Variety Roller Chains

Heavy roller chain

 

Hefty responsibility roller chains are created to ANSI B29.1 but have thicker side panels. The thicker side panels not only display improved power and exhaustion resistance of the roller chain, but also decrease stretching and use more than time. Hefty duty roller chains are the best selection for agricultural apps, skid steer loaders, heavy tools and any application exactly where you want to boost the chain strength CZPT rising the measurement. Roller chains and sprockets have the widest selection of weighty chains. Standards offer one, double, triple, double pitch and even heavy duty roller chains. Nevertheless, if you don’t see the solution you need, you can make a personalized large obligation roller chain as essential.

 

Overview
A chain is a versatile section consisting of adjacent similar or comparatively equivalent sections. All machinery, mechanisms, and chains utilized on the equipment are collectively referred to as the industrial chain. A shut chain and two sprockets type a system to understand the transmission of the transmission chain. In comparison with gear generate and belt travel, this push has the pursuing attributes:
(1) Multi-tooth bearing, protected and dependable
(2) Flexible transmission to take in shock and vibration
(3) The centre distance range is large, and the manufacturing and installation accuracy requiremSpecialty Chains: A Special Choice for Your Specific Undertaking Sometimes a standard roller chain simply just isn’t appropriate for your task – you happen to be both in a difficult atmosphere or have large-obligation needs or demanding applications. Although we also offer you machining choices for chains and attachments, these “standard” specialty chains are our most common. Do you want nails to the prime of a chain or binding chain? no difficulty! Our expert chain merchants are usually at your services. From spires to facet bows, each of our specialty chains is built to exacting ANSI specifications, so you can be self-assured your machine will operate as anticipated without having unforeseen failures or chain bends.
ents are low
(4) In contrast with the belt drive, the transmission ratio is correct, the transmission efficiency is larger, and it is ideal for harsh environments these kinds of as higher temperature, dust, and humidity.
The chain composition is fairly simple, labor-intense, and accompanied by sounds pollution. In recent a long time, the world’s significant industrial nations around the world have gradually replaced labor-intensive and materials-intense goods with engineering-intensive merchandise, and most of them have shifted from domestic items to imported merchandise. At the very same time, compared with mainframes or comprehensive sets of equipment, these items do not call for a great deal of right after-revenue solutions, opening the doorway for my country’s export chain.
two. Production
The chain adopts a procedure route that combines mechanical and warmth treatment method processes and is formed by means of content modification, stamping forming, heat treatment strengthening, assembly (or welding), and other processes. At existing, most domestic enterprises use special planes, automated traces, or production traces for processing and production, and some enterprises also insert non-damaging screening in important processes.

China Professional Heavy Duty Chain Toothen Side Metal Stainless Steel China Series Large Pitch Best Price CZPT Special Attachments Double Sharp to Type Roller Chains     near me shop

China manufacturer Heavy Duty Series Cottered Type Roller Chains wholesaler

Solution Description

chain number: 10AH-1, 12AH-1, 16AH-1….40AH-three
content: 40Mn or stainless metal

Specialty Chains: A Distinctive Decision for Your Specific Project Occasionally a normal roller chain just just isn’t right for your undertaking – you are either in a difficult surroundings or have weighty-obligation specifications or demanding purposes. Whilst we also offer machining possibilities for chains and attachments, these “common” specialty chains are our most popular. Do you need to have nails to the top of a chain or binding chain? no problem! Our specialist chain retailers are alwayChain Wear A roller chain is a sequence of related journal bearings that articulate as they enter and depart the sprocket. This articulation can result in pin and bushing put on. As the material wears absent from these surfaces, the roller chain will steadily elongate (Determine 1). Comprehension Roller Chain Dress in Elevated daily life owing to put on is a standard phenomenon for the duration of generate procedure. The put on fee is dependent on numerous aspects these incorporate proper lubrication, load, and the frequency and diploma of articulation in between the pin and bushing. The manufacture of vital put on areas, nails, and bushings need the strictest attention to detail. It begins with the correct choice of raw supplies, portion fabrication, and element preparing just before assembly, including assembly. All of these are vital elements for ideal efficiency. If the put on components are not of the optimum good quality, the dress in daily life of the roller chain will experience no matter of other elements.
s at your service. From spires to aspect bows, every of our specialty chains is developed to exacting ANSI expectations, so you can be assured your machine will work as anticipated without having unexpected failures or chain bends.

China manufacturer Heavy Duty Series Cottered Type Roller Chains     wholesaler