Conveyor chains are frequently required to operate in arduous and challenging environments, from the transport of biomass fuels to cement, steel-work, recycling, paper and pulp and food processing industries. These are demanding applications that rely on the use of industrial chain and components that have the strength and durability to withstand wear.
1. Split sprockets
Conveyor chain sprockets are often large and heavy and will frequently require the use of a crane to get the sprocket in place.
If an engineer is having to dismantle large parts of the drive, or if there are multiple sprockets being fitted on the same shaft, then this can mean significant periods of machine downtime. A solution to this problem is the use of a split sprocket.
Split sprockets can prove especially useful in high-wear industry applications such as cement and recycling. However while in theory they all do the same job, not all split sprockets are created equally.
Some industrial chains manufacturers, for example, will look to create a split sprocket by essentially cutting an existing sprocket in half and then rejoining the two sections back together. The problem with this approach is that it can result in a poorly assembled component which can increase the risk of uneven distribution of load and decrease the wear-life of the sprocket teeth, bore and key-ways.
To increase the chances of trouble-free operation, it is recommended to select a split sprocket that has been manufactured as two separate segments so the two mating sections can then be perfectly aligned.
2. Shear pin sprockets
Shear pins help to prevent damage to machinery due to sudden overloading by shearing the pin at a predetermined load.
The conveyor chain sprocket can rotate freely, allowing the drive to spin and preventing damage to the conveyor chain, drive motor or conveyor.
While it's true that shear pin sprockets can be more expensive than standard sprockets, over time they can prove their true worth by getting your conveyor moving quickly again, reducing your machine downtime and saving on replacement costs.
3. Induction hardened teeth
The induction hardening of conveyor chain sprocket teeth can extend conveyor chain sprocket life, particularly in heavy load drives or in severe or abrasive environments.
Hard conveyor chain bores however, are well known to cause premature wear on shafts, so it is important that only individual teeth profile has been hardened so the bore remains soft and ductile.
4. Odd vs even numbers of teeth
The introduction of sprockets with even numbers of teeth was intended to offer customers a greater degree of choice when designing chain conveyor systems.
In reality though, when the same teeth are repeatedly engaged by the rollers on each rotation, this can often result in uneven wear.
If the number of teeth in the smaller sprocket is a divisor of the number of pitches on the conveyor chain, then you'll also be likely to see a vastly increased amount of chain wear.
Conversely, choosing a sprocket with an odd number of teeth has been shown to result in at least double the service life of the chain.
5. Double pitch sprockets
Double pitched sprockets are often overlooked these days, but if your conveyor chain is compatible they can be an ideal solution to save on space and extend the wear life of your chain.
Double pitch sprockets have more teeth than a standard sprocket of the same pitch circle diameter which means they distribute wear more evenly across the teeth.
6. Sprocket alignment
Whenever a sprocket is replaced it is essential that it is correctly aligned with the shafts to ensure accurate distribution of load across the entire chain width.
To check for signs of wobble a straight edge, nylon line or laser sight tool should be used across the machined faces of the sprocket in several positions. Once the sprocket has been aligned you can then drive the keys home as a final check.
Conveyor chain applications rely on the highest quality materials and manufacturing methods to ensure optimum strength, durability and resistance to wear.
Making sure you've selected the right sprocket for your conveyor system can offer significant benefits in reducing machine downtime and prolonging the service life of your chain.