Chain drives are used most of the time to transport power from one component to another at a longer distance; however, they may also be utilized for shorter distances.
They are one of the most common mechanical power transmission techniques, along with shaft couplings, gear drives, belt drives, and lead screws.
Because each approach offers a unique set of benefits and drawbacks compared to the others, engineers need to exercise extreme caution before settling on one strategy.
We’ll look at chain drives and the many different types of chain drives available in this post. They are an essential component of a wide variety of devices.
In addition to their function in the transmission of power, they have a variety of other potential uses as well (but more on that later). So let us begin from the very beginning, shall we?
What Exactly is a Chain Drive?
Before delving into the different types of chain drive, let us first find out what a chain drive is.
A chain drive is a specific mechanical power transmission system that moves power from one location to another by using chains to make the transfer.
A standard chain drive will include anywhere from two to multiple sprockets in addition to the chain itself. The chain links have large holes to accommodate the sprocket teeth.
When the prime mover turns, the chain wrapped around the sprocket on the shaft also turns. This then imparts a mechanical force onto the driven shaft, which results in mechanical power transmission.
A chain drive’s ability to maintain a constant speed ratio owing to its zero slip characteristic is one of its primary benefits compared to a belt drive’s ability to do the same.
In addition, since there is no delay in the transmission of power, it may be used as a timing chain in applications like internal combustion engines.
The absence of slippage also ensures a high level of mechanical efficiency. The only kind of loss that may occur with a chain drive is frictional loss, which occurs when the chain links rub against the sprocket.
Chain drives are much more adaptable than gear drives regarding the range of distances they can function.
This is because they come into action in situations in which the distance between two shafts is larger than the maximum distance for which gears are practicable.
Chain drives are effective across a wide range of distances while maintaining a relatively small footprint in the system.
They may be found in applications that cover a little distance, such as bicycles, and applications that cover a vast distance, such as naval engines that are five stories high.
A single chain may power multiple shafts at the same time. So what are the different types of chain drive? The next paragraph discusses that.
Different Types of Chain Drive
Because chain drives may be used in various mechanical contexts, designers have invented a dizzying array of unique chain drive configurations.
Depending on the criteria we use to measure them, they might be placed in several different groups.
Chain drives may be broken down into three types when their functionality is considered. Below are the three different types of chain drive.
- Conveyor chain drive
- Power transmission chain drive
- Hoisting and hauling chain drive
Conveyor chain drive
One of the different types of chain drive, conveyor chains are yet another typical use for chain drives. Chain drives made specifically for the conveyance of materials are used in conveyors.
They are available in many unique designs, each with its benefits, such as minimal friction, high-temperature resistance, and chemical inertness. In addition to that, they might be magnetic and anti-static.
The packaging, automobile, food and beverage, pharmaceutical, and textile industries all employ conveyor chain drives.
Conveyor chains may have numerous attachments attached to them so they can be used for various purposes.
Power Transmission Chain Drive
The power transmission chain drive, one of the different types of chain drive, is used to transfer power from one shaft to another.
The vast majority of equipment that generates electricity cannot be consumed at the same location, such as pumps that also include motors.
Transmission systems provide electrical electricity to consumers through a variety of various channels. When chains are used this way, we refer to those particular chains as power transmission chains.
Bicycles, farm equipment, compressors, engine camshafts, and other similar components are all examples of common instances. The power transfer in all of these applications is accomplished via chain drives.
Chain Hoisting and Hauling Driving Mechanism
Chain hoists are the most prevalent piece of machinery used to raise and lower other pieces of machinery. Using pulleys, they can raise enormous weights with very little effort. They are among the three different types of chain drive.
Hand chain hoists, also known as chain blocks, are a ubiquitous piece of equipment found in many companies, as well as garages, workshops, building sites, and ship engine rooms.
They can raise or lower weights weighing up to 20 tons. There are also manual, pneumatic, and electrical options for hoisting chains.
We will devote the next section to discussing the many categories of chains; however, due to the simplicity of both their construction and the industries in which they are used, we will discuss hoisting chains right now.
There are two distinct types of hoist chains, and they are as follows:
- Oval link chain
- Stud link chain
Oval link chain
Chains with oval links are sometimes referred to as coil chains. They are often employed as hoisting chains for weights ranging from light to medium, and they are designed to be used in lifting applications that include a slow lifting speed.
The chain link has an oval form, and when the links are interlocked, each one is welded shut.
It is possible to use chains with square links occasionally; however, this chain is often avoided owing to its poor stress distribution and kinking concerns.
Stud Link Chain
When it comes to high-load applications, stud link chains are the superior solution. Across the inside of the link of each chain is a stud that has been attached.
In addition to increasing strength and longevity, the studs prevent the cable from kinking. Ship anchors and other heavy-duty lifting machinery use stud link chains for their lifting applications.
Different Kinds of Chains Used in Chain Drive
We have already talked about the different types of chain drive available in the mechanical world; now, we will be looking at the different types of chains used in chain drive.
Chain drives use various chains, each of which has benefits and drawbacks. The following are the five varieties that are used the most frequently:
- Flat-top chain
- Silent chain or inverted tooth chain
- Leaf chain
- Roller chain (bush roller chain)
- Engineering steel chain
Flat Top Chain
Flat-top chains have no other purpose save that of communicating. However, because the material may be transported directly on its links, they can serve as an alternative to conveyor belts and the belt drives that go with them.
A single link is typically fabricated from a steel plate that has hollow protrusions in the form of a barrel on the bottom side of the plate.
A pin is inserted through these protrusions below the links to connect them to the links that came before them and those that will come after them.
Because of how these joints are constructed, there is only one possible direction of movement. Specialized varieties of flat-top chains can bend in a sideways direction.
The structure of the pin makes it possible for the conveyor chain to travel laterally in both directions, which enables it to navigate around bends.
For material transportation along assembly lines, low-speed conveyor machines with flat top chains as their drive mechanism are used.
The flat top chain is one of the different types of chains used in any of the different types of chain drive.
Silent Chain (Inverted Tooth Chain)
The majority of chain drives are notorious for the significant operating noise that they produce. Therefore, a chain that produces less noise is preferable in places sensitive to sound pollution, such as confined spaces, mines, and residential areas.
The disruption to the environment around them is kept under control as a result, which is also beneficial to the well-being of the workers.
Then there are quiet chains, also referred to as inverted tooth chains. The functioning of a silent chain may be kept very quiet even if it can transmit significant quantities of electricity at rapid speeds.
The link chain is made up of flat plates that have been piled in rows and joined with at least one pin each. On the underside of each link, where it contacts the sprocket teeth, there is a curve miming the shape of sprocket gear teeth.
The amount of flat plates included inside each link of a silent chain contributes to the improvement in tensile strength and the expansion of the chain’s load capacity.
These are the most basic forms of chains that may be found in usage. They solely include pins and link plates in their construction.
The link plates are constructed by alternating between a pin and an articulated link. Because leaf chains are intended to run across sheaves for guiding, they do not mesh with the teeth of sprockets.
There are applications for lifting and counterbalancing that make use of leaf chains. Applications such as lifts, lift trucks, forklifts, straddle carriers, and lift masts are typical devices that use leaf chains.
In these machines operating at low speeds, the lift’s chain is subjected to substantial static stresses and a small working load. Compared to other chain designs, leaf chains are superior in their ability to withstand stress and inertia.
Every single one of the lift chains has to be able to withstand significant tensile pressures without being stretched out or snapping. In addition, they need to have enough flexibility to withstand fatigue.
Therefore, lubrication and the operating environment are two factors that must always get enough consideration throughout the early stages of product design.
Roller Chain (Bush Roller Chain)
When people think of chains, the roller chain is generally the first kind that comes to mind. Roller chains, also known as bush roller chains, are often used in the transportation sector for power transmission in applications such as bicycles, motorcycles, and other vehicles. In most cases, they are crafted from carbon steel in its most basic form or from steel alloys.
An inner plate, known as a roller link plate, and an outer plate, known as a pin link plate, as well as bushes, pins, and rollers, make up a roller chain. The rollers are spaced at equal intervals between each link in the chain.
These rollers interact with the teeth of the sprocket to facilitate the transmission of power along the chain. When roller chains come into contact with the teeth of the sprocket, they spin as necessary, which results in a reduction in the amount of power that is lost. This is an essential benefit of roller chains.
Regarding transmission chains, the roller chain link plates (located on each side of the roller) have a height larger than the rollers themselves.
During operation, the side plates will not touch the sprocket since this will be in place. In addition to that, they serve as guides and stop the roller chain from sliding off the track when it is not in use.
When it comes to roller chains used in conveyors, the diameter of the rollers is often much more than the height of the sidebars.
This eliminates translational friction, which increases operational efficiency and prevents the sidebars from coming into contact with the conveyor track. Additionally, larger rollers lower the amount of friction caused by rotation.
Roller chains with several strands are an option for designers tasked with meeting increased power demands. Because there are numerous strands, it is possible to employ slower chain speeds and smaller chain pitches while still meeting the load requirements.
Engineering Steel Chain
Since the 1880s, engineers have been using chains made of engineering steel. This chain was developed to withstand the harshest conditions and meet the requirements of the most challenging applications.
They were constructed from steel rolled at a high temperature and were occasionally heat-treated to increase their durability.
Chains made of steel are just as important in modern engineering. However, to satisfy the requirements of modern industry, their tensile strength, wear rate, loading capacity, and pitch have all been improved.
These chains are made up of links and joints that look like pins. Because it must function normally in the presence of particles of dirt, dust, and abrasives, the clearance between the components of this chain is higher than the clearance between the components of other chains.
Most engineering steel chains are used as conveyor chains for material handling; however, some chains are also used in drives.
As a result, they are used in various applications, including conveyors, forklifts, bucket elevators, and oil drilling equipment, to name a few.
How to Choose Which Chain Drive is Most Suited for Your Particular Application?
Because there are so many different types of chain drive and their designs, each with its unique appearance and set of capabilities, it may not be easy to choose the best chain drive for a certain application.
Eliminating possibilities that are not appropriate for this selection should be your first step. You can do so by analyzing the chain’s functionality and its characteristics. Before making the ultimate decision, this will reduce the number of possibilities.
The following is a list of the most significant considerations to make when choosing a chain drive:
- Chain velocity
- Service environment
- Shaft layout
- Distance between the shafts
Not all chain drives are capable of operating in high-speed environments. There are chain drives available that are optimized for use at slower speeds.
Calculations need to be done to determine whether or not the speed falls within the acceptable range, and then the results may be used to derive the requirements.
Due to this examination, the number of possible designs that may be implemented for this application will be significantly reduced.
The chain drive’s predicted resistance to moisture, filth, abrasives, corrosion, and high temperature will be determined by the service environment in which it will be used.
In addition, other characteristics will be influenced, such as vibration, noise levels, and fatigue strength. For instance, the designers can use an inverted tooth chain in locations concerned about noise levels.
The Layout of the Shafts
Most chain drives cannot function with shafts that are not parallel to one another. So the designers may have no choice but to consider gear drives as an option if the shafts aren’t perfectly aligned.
When choosing the best chain drive for your application, the issue of how much power has to be transmitted should be the primary focus of your attention. The chain has to have the capacity to deal with the power that the prime mover generates.
At this point, the accuracy of the calculations will determine not only the safety of the crew but also the effectiveness of the chain drive system. Therefore, it is strongly suggested to operate with an appropriate level of safety factor.
Space Between Each of the Shafts
It is strongly suggested that the spacing in the middle of the chain between the shafts be 1anywhere between 30 and 50 times the chain pitch.
In addition, the designer is responsible for ensuring that the smaller sprocket has a minimum arc of contact equal to or greater than 120 degrees.
Finally, when there are a limited number of sprocket teeth, there must always be at least five of them in contact with the chain at any one time.
Lubrication is necessary for most chain drives to achieve a good wear life. The necessity for chain lubrication will be determined by the chain type, size, weight, and operating speed, respectively.
Depending on the application, designers may prefer lubrication techniques such as manual drip feed, oil bath, or forced feed.
Some chains are self-lubricated, meaning they do not need further lubrication throughout their service life.
These types of chains make use of bushings that are constructed from oil-infused sintered polymers or metals, which provide continuous lubrication while the chain is in use.
Benefits of Using the Different Types Of Chain Drive
Many benefits and advantages are associated with using any of the different types of chain drive. They are:
- Having the capacity to transmit torque across considerable distances
- A chain drive, unlike a belt drive, does not experience slippage.
- A chain drive is more space-efficient than a belt drive. Therefore, it may be used in areas with limited clearance.
- One chain drive may provide power to several different shafts.
- Drive that is versatile and able to function well in a wide range of temperatures and conditions of service (dry, wet, abrasive, corrosive, etc.)
- This system has a low friction rate, which ensures that it has high mechanical efficiency.
Different Types of Chain Drive Have Several Drawbacks
Some of the major drawbacks peculiar to the different types of chain drive are:
- It cannot function with shafts that are not parallel.
- Chain drives are notorious for their loud noise, and they are also capable of causing vibrations.
- Incorrect alignment may result in the chain being dislodged.
- Some designs need continual lubrication.
- In most cases, an enclosure is required.
- They periodically need to adjust the chain tension, which is done by tightening an idler sprocket on the chain.