Phenolic wear bands were a mainstay in hydraulic cylinders, however due to the formaldehyde content, they have largely been replaced by glass-filled nylon. If compressive strength requirements are below 25,000 psi, glass-filled nylon is the best bet. Suppliers stock the common sizes, and you can avoid a costly penalty. Uncommon phenolic sizes can be ten times the cost of glass-filled nylon, and with nylon, you don’t have to worry about a visit from OSHA.
by Bruce MacIntyre, AY Seal and Packing Co. (firstname.lastname@example.org)