Chain drives are perfect for small center distances and can be used up to 3 meters in most circumstances, but up to 8 meters in extreme cases. Chain drives may transmit up to 100 kW of power and have a peripheral velocity of up to 15 m/s. It’s possible to have an 8:1 velocity ratio.
The fundamental problem of belt and rope drives is that the velocity ratio does not remain constant and fluctuates due to slip. Because chain drives are positive drives, they don’t slip, hence the velocity ratio is constant.
Bicycles, motorbikes, rolling mills, agricultural machinery, machine tools, conveyors, coal cutters, and other power transmission applications all use chain drives. A chain drive is made up of two wheels called sprockets and a chain. The sprockets are toothed wheels that are fitted with an endless chain.
In this article, you’ll learn the various types of chain drives. You’ll also learn their advantages and disadvantages.
Read more: Understanding chain drive
Types of chain drive
The followings are the common types of chain drive used for power transmission:
- Roller chain
- Silent chain
- Leaf Chain
- Flat-top Chain
- Engineering Steel Chain
Conveyors, wire- and tube drawing machines, printing presses, vehicles, motorcycles, and bicycles are all examples of home, industrial, and agricultural machinery that use this sort of chain to transmit mechanical power.
A roller chain is made up of a succession of short cylindrical rollers connected by side links. A toothed wheel called a sprocket drives it. It is a power transmission system that is simple, dependable, and efficient. The diameter of these chains is usually less than the height of the link plates. When the chain engages the sprockets, the link plates act as guides.
Chains can also be used as a guide to support material carried on rails or routes, which is common in conveyors and bucket elevators. Both driving and conveyor applications use roller chains.
- The single-strand standard series roller chain is the most popular driving chain. These chains’ power rating capacities cover a broad range of drive load needs. Multiple-strand roller chains are used to increase power capacity without altering the pitch or linear speed of the chain.
Flat-top chains are commonly used on conveyors, with the slat conveyor being the most common application. A series of steel top plates with hinge-like barrels curled on each side make up the Flat-top chain. To form a joint, pins are placed through the barrels.
These serve as both bearings and beams. Pins are held in place in the barrels of one top plate by press fits or headings but are free to articulate in the barrels of the following link. To keep the connecting pin in one of the top plate’s barrels, it’s frequently knurled or expanded on one end. As a result, a continuous length of flat-top chain is created. Only conveying is the purpose of the flat-top chain.
Engineering Steel Chain
Engineering steel chains were first developed in the 1880s for challenging conveying applications. Conveyors, bucket elevators, and tension linkages all use engineering steel chains. There are only a few that are used in drives. Tensile loads, various types of wear, lubrication, and the environment are the key design issues for these chains.
When building an engineering steel chain, the most significant parameters to consider are the following. Conveyor chain wear includes joint wear, roller and bushing wear, as well as sidebar and track wear.
Read more: Understanding powertrain and drivetrain
The silent chain, also known as the inverted tooth chain, is made up of a succession of toothed link plates attached to joint components in such a way that they can flex freely between pitches.
Silent chains are made up of stacked rows of flat link plates with gear-like shapes that contact sprocket teeth in the same way that a rack engages a gear, as seen in the diagram. One or more pins hold the links together at each chain joint, allowing the chain to stretch.
Silent chains from various manufacturers are typically unable to be joined. Silent chains are utilized in a wide range of industrial applications that demand a small, high-speed, smooth, low-noise drive.
High-performance silent chains come in a variety of diameters, pitches, and widths, and are utilized on extremely high-speed drives that demand outstanding smoothness and quietness. These chains are typically used in industrial equipment that requires extreme smoothness.
The purpose of leaf chains is to elevate rather than transmit power. Tensions are high, but the pace is slow. Normally, the chains only work on a sporadic basis. Tensile loads, joint wear, and link plate and sheave wear are all important factors to consider while designing leaf chains.
Leaf chains are not compatible with sprockets since they are designed to run over sheaves and have no provision for engaging a sprocket. Because leaf chains are frequently used to carry enormous loads, they must have a high yield strength and not be permanently stretched when doing so. The most prevalent application for leaf chains is on lift trucks.
Below are some other common types of chain drive:
Automobile Chain Drive
A chain-drive system in a vehicle transfers power from a differential to the rear axle. Chain drives were a prominent power transfer device in the early days of automobiles. With its rigid Hotchkiss, Driveshaft, and universal joints, it became a popular alternative to the Système Panhard.
Driveshafts and universal joints are more difficult to design than chain drives. It allows the suspension to react to bumps more effectively since there is less unsprung weight at the rear wheels. This would result in a smoother ride for the automobile.
Read more: Understanding drive belt
Bicycle chain drive
The majority of bicycle chains are constructed of ordinary carbon or alloy steel; however, some are nickel-plated to prevent rust or for aesthetic reasons.
The key feature that defined the safety bicycle, which was launched in 1885 and featured two equal-sized wheels, from the “high wheeler” style of bicycle, was chain drive. The popularity of chain-driven safety is still a common component of modern bicycle design.
The efficiency of a bicycle chain is high because it shifts the center of the pressure away from the axle, decreasing stress on the bearings and lowering friction in the inner wheel. It was discovered that a higher chain tension was more efficient.
Advantages and disadvantages of Chain drives
The following are the advantages of chain drives in their various applications:
- They’re non-sail positive drives.
- The level of efficiency is really high (up to 99 percent).
- It can be used for shafts with modest as well as large center distances up to 3 meters.
- They can achieve a high-velocity ratio of up to 8:1 in a single step.
- They are capable of transmitting more power than belt drives.
- When compared to belt drives, sprockets put less stress on the shafts since they are lighter than pulleys.
- They can work under difficult temperature and climatic conditions, unlike belt drives.
- They are more compact and take up less space than belt drives.
- The cost of upkeep is minimal.
Despite the good benefits of chain drives, some limitations still occur. The followings are the disadvantages of chain drives in their various applications:
- Both the driving and driven shafts should be perfectly aligned with their axes parallel.
- More lubrication is required.
- The initial cost is quite high.
- The operation cannot have periodic reversals due to the stretching of the chin.
- There are more variations in velocity.
Read more: Understanding pulley and belt
That is all for this article, where the common types of chain drives are been discussed. The advantages and disadvantages of these chain drives are also explained. I hope you learn a lot from the reading, if so, kindly share with other students. Thanks for reading, see you around!