A roller chain is a type of chain used to transmit mechanical power. It is a type of chain drive and is widely used in household, industrial and agricultural machinery, including conveyors, plotters, printing machines, automobiles, motorcycles, and bicycles. It is linked together by a series of short cylindrical rollers and driven by a gear called a sprocket, which is a simple, reliable and efficient power transmission device
1 .Introduction to Roller Chain：
Roller chains generally refer to precision roller chains for short-pitch transmission, the most widely used and the largest output. Roller chains are divided into single row and multi-row, suitable for small power transmission. The basic parameter of the roller chain is the chain link p, which is equal to the chain number of the roller chain multiplied by 25.4/16 (mm). There are two kinds of suffixes in the chain number, A and B, indicating two series, and the two series complement each other.
2. roller chain composition：
The roller chain is composed of an inner chain plate 1, an outer chain plate 2, a pin shaft 3, a sleeve 4 and a roller 5. The inner chain plate and the sleeve, the outer chain plate and the pin are all interference fits; the rollers and the sleeve, and the sleeve and the pin are all clearance fits. When working, the inner and outer chain links can deflect relative to each other, the sleeve can rotate freely around the pin shaft, and the roller is set on the sleeve to reduce the wear between the chain and the sprocket. In order to reduce the weight and make the strength of each section equal, the inner and outer chain plates are often made into an “8″ shape. [2] Each part of the chain is made of carbon steel or alloy steel. Usually through heat treatment to achieve a certain strength and hardness.
3.Roller Chain Chain Pitch:
The center-to-center distance between two adjacent pin shafts on the chain is called the chain pitch, denoted by p, which is the most important parameter of the chain. When the pitch increases, the size of each part of the chain increases accordingly, and the power that can be transmitted also increases accordingly. [2] The chain pitch p is equal to the chain number of the roller chain multiplied by 25.4/16 (mm). For example, chain number 12, roller chain pitch p=12×25.4/16=19.05mm.
4.The structure of the roller chain：
Roller chains are available in single and multi-row chains. When it is necessary to bear a larger load and transmit a larger power, multiple rows of chains can be used, as shown in Figure 2. Multi-row chains are equivalent to several ordinary single-row chains connected with each other by long pins. It should not be too much, commonly used are double-row chains and three-row chains.
5.Roller link joint form：
The length of the chain is represented by the number of chain links. Generally, an even-numbered chain link is used. In this way, split pins or spring clips can be used at the joints of the chain. When the curved chain plate is under tension, additional bending moment will be generated, and generally should be avoided as far as possible
6.Roller chain standard：
GB/T1243-1997 stipulates that roller chains are divided into A and B series, among which A series is used for high speed, heavy load and important transmission, which is more commonly used. The chain number multiplied by 25.4/16mm is the pitch value. B series is used for general transmission. The marking of the roller chain is: chain number one row number one chain link number one standard number. For example: 10A-1-86-GB/T1243-1997 means: A series roller chain, the pitch is 15.875mm, single row, the number of links is 86, the manufacturing standard GB/T1243-1997
7.Application of roller chain：
Chain drive is widely used in various machinery in various industries such as agriculture, mining, metallurgy, petrochemical industry and lifting transportation. The power that the chain transmission can transmit can reach 3600kW, and it is usually used for power below 100kW; the chain speed can reach 30~40m/s, and the commonly used chain speed is below 15m/s; ~2.5 is suitable.
8.Features of roller chain drive：
advantage：
Compared with the belt drive, it has no elastic sliding, can maintain an accurate average transmission ratio, and has high transmission efficiency; the chain does not require a large tension force, so the load on the shaft and bearing is small; it will not slip, the transmission is reliable, and the overload Strong ability, can work well under low speed and heavy load.
shortcoming：
Both the instantaneous chain speed and the instantaneous transmission ratio change, the transmission stability is poor, and there are shocks and noises during operation. It is not suitable for high-speed occasions, and it is not suitable for frequent changes in the direction of rotation.
9.invention process：
According to research, the application of chains in China has a history of more than 3,000 years. In ancient China, the dump trucks and waterwheels used to lift water from low to high are similar to modern conveyor chains. In the “Xinyixiangfayao” written by Su Song in the Northern Song Dynasty of China, it is recorded that what drives the rotation of the armillary sphere is like a chain transmission device made of modern metal. It can be seen that China is one of the earliest countries in chain application. However, the basic structure of the modern chain was first conceived and proposed by Leonardo da Vinci (1452-1519), a great scientist and artist in the European Renaissance. Since then, in 1832, Galle in France invented the pin chain, and in 1864, the Slaite sleeveless roller chain in Britain. But it was the Swiss Hans Reynolds who really reached the level of modern chain structure design. In 1880, he perfected the shortcomings of the previous chain structure, designed the chain into the popular set of roller chains, and obtained the roller chain in the UK. chain invention patent.
Post time: Mar-13-2023
