Epoxybearing

Epoxybearing is a term used for bearings that use epoxy resin as the primary binding or matrix material, typically in polymer-composite or epoxy-impregnated configurations. These bearings are designed to provide low friction, chemical resistance, and, in some versions, self-lubricating behavior in environments where conventional lubricants are undesirable.

Construction and materials: Epoxy bearings may be reinforced with glass, carbon, or aramid fibers to increase stiffness and load capacity. They are also commonly filled with solid lubricants such as PTFE, graphite, or bronze powders to improve wear resistance and reduce friction. In epoxy-impregnated bearings, a porous metal housing or insert is saturated with cured epoxy resin that contains lubricants, creating a self-lubricating bearing surface.

Properties and performance: Epoxy bearings offer good chemical resistance, moderate strength-to-weight, and electrical insulation. They generally operate at lower temperatures than metal bearings and depend on the filler system for wear performance. Potential drawbacks include lower thermal conductivity, lower temperature limits, and variability in wear if the filler or resin distribution is uneven.

Manufacturing and testing: Manufacturing methods include compression molding, resin transfer molding, and casting followed by curing. Parts are machined to final dimensions and subjected to tribological tests to determine friction, wear, and load capacity. Compatibility with operating fluids and solvents is also evaluated.

Applications and context: Epoxybearings are used in aerospace, automotive, and industrial equipment where chemical resistance, low weight, or limited lubrication are priorities, such as in corrosive or clean environments. They are not universal replacements for metal bearings and are selected when formulation and operating conditions align with epoxy's performance envelope.