A rod worn on one side is a sign of a sideways movement of some kind either from a lack of bearing support (perhaps from bearing failure), or else too much side load which can be a result of misalignment or misuse. The rod itself may actually be under specified for the load and so the use of the cylinder should be checked to make sure it is being used within specification.
A repair will provide an opportunity to not just fix the problem, but raise the specification of the assembly by increasing the rod size, increasing the bearing area or incorporating external guides. A combination of all three is also possible.
Company Resource: Air cylinder, Standard cylinder, Micro cylinder
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