The "Chain" coupling is considered a "flexible" coupling, although they're really pretty rigid when connected. And while they will withstand some misalignment, the perfect application would have the attached equipment be Laser Aligned, or properly aligned with dial indicators and a lot of skill.The total coupling is made up of 4 components. The main components are 2 sprockets with hardened teeth (not just ordinary sprockets), bored to proper dimensions for mounting on the driver and driven shafts. These sprockets are available as "taper-lock" type of bushings as well for easier mounting and flexibility. The second component is a "double-row" roller chain of the proper pitch to mate with the sprockets. And finally, we have an outside "Case" that covers the complete chain and sprocket mechanism and is there to keep the lubricating grease from flying around during shaft rotation.
Mounting of the sprockets is rather straight forward in that they are mounted on the driver and driven shafts and positioned with the proper clearance between them so that the roller chain wraps around the sprockets and meshes properly with the teeth.
The body consists of two dedicated sprockets with hardened teeth and a two-strand roller chain. The sprockets are coupled when the chains are wound around the sprockets, and decoupled when the chains are removed. Therefore, transmission power can be coupled or separated without moving the transmission system, which can be a real plus for some equipment.
For ease of mounting and inspection, the casing can be separated at a right angle to the shaft. The mating part to the hub is finished precisely to hold the hub firmly with no eccentricity. Furthermore, the other hole has a trapezoidal groove into which an oil seal is inserted for the prevention of oil leakage while holding the sprocket boss flexibly so that the flexibility of the coupling will not be lost. The coupling life is notably extended due to the prevention of both lubricant spatter and the infiltration of dust particles when installing the casing, which ensures effective lubrication. The casing protects the unit from corrosion and ensures safe operation. If the coupling is used under frequent start and stop operation or excessive vibration, contact the manufacturer for proper recommendations.
One manufacturer has the following three lubrication systems recommended when using Roller Chain Couplings. The choice depends on the operating speed.
Lubrication System I - Apply grease regularly on a monthly basis.
Lubrication System II - Apply grease regularly on a weekly basis, or mount the casing filled with grease. Lubrication System III - Mount the casing filled with grease. For System III, it is especially important to use high-grade grease because of the grease may stick to the inner surface of the case due to centrifugal force, resulting in poor lubrication. Lubrication frequency and type of grease will depend on the specific manufacturer, so be certain to check the operating instructions that come with the unit.
One special design of the "chain" coupling has the chain and cover made of Nylon. This allows the coupling to be used in atmospheres such as the "Food" industry. The coupling requires no lubrication and is therefore significantly cleaner than those requiring lubricating grease on a regular basis.
So depending on your actual application, A.R.&E. can assist you in the proper selection of a Chain Type Coupling, if that's best, and supply it for you when you're ready to purchase.