Upper Sprocket Assembly,
Spare Part of the Month, July 2015
Description: This part is an upper sprocket assembly found on a S/RM and is considered a key part of the vertical hoist mechanism. A S/RM is typically found with two upper and two lower assemblies. While the lower assemblies are actually driven by electric gear motors in order to move the chains, the upper assemblies act as an idler and support for the chains within this hoisting function.
Why it’s important: All the sprockets, including the chains, are vital to the operation of the hoist mechanism, which supports the movement of the Vertical Lift Station to lift product to the different levels and positions of a storage rack. There is a large amount of weight and load on the different components of the hoist mechanism, which exposes the sprockets to the same stress and makes it critical to the operation. A damaged or worn assembly, which can contain multiple parts, can cause premature failure of the chain or other components within the chain drive. Wear or damage is typically found in the form of deformed or worn sprocket teeth, bearings that are seized or falling apart, or leaking grease seals.
Recommendation: With proper maintenance and care, these assemblies along with the other chain drive components, will give you hassle free operation. A key way to maintain these assemblies is to make sure the chains are adequately lubricated, as well as tensioned. Be sure that the sprocket assemblies have fresh grease in them. Some assemblies require hand-packing grease and others have a grease fitting (as pictured) for use of a grease gun. In some cases, you may have a sealed type bearing. If these are found to be leaking, they should be replaced. Follow the maintenance intervals recommended in your S/RM manual for knowledge on when to carry out these functions. In the case that a sprocket assembly is found to be damaged or worn, it is vital that they be addressed immediately in order to preserve other components of the chain drive and avoid further damage and downtime. Due to the critical nature of this item, we recommend that all customers keep one or two of these assemblies on-hand for a quick turn-around if one has failed.