|Phenolic Resin - Cotton Fabric Substrates
These products consist of phenolic resin systems combined with several weights of cotton fabrics, from less than four ounces per square yard (commonly called "linen") to 6, 8, 10, and 25 ounces per square yard, used in bearing grades for ships. These phenolic sheets are easy to machine and operate with less noise than metal in numerous gear and bearing-type applications. In addition, they do not spark when struck, so they can be used in explosion-proof environments. These structural and electrical insulation materials are also less abrasive than fiberglass options in wear applications. Phenolic/canvas composites can be used to make a variety of parts, including gears, pulleys, rollers, and guides. In the phenolic/linen product line, grades include bleached linen to enhance moisture resistance, electrical insulation, and other properties. The resin systems can be modified in various ways to suit requirements, including the addition of lubricants that reduce wear. Phenolic/linen products offer a lower coefficient of thermal expansion than thermoplastic materials, as well as more strength and heat resistance than all but the most expensive thermoplastics. Applications include small gears, pulleys, rollers, guides, and other parts that are more intricate than those made with canvas grades.
Bearing grade laminates consist of multiple plies of a very heavy weight canvas cloth impregnated with phenolic resin and laminated under heat and pressure to produce a thermoset (non-melting) material. Canvas weights and resin formulations can be changed to modify the finished properties of the composite laminate. The load-bearing properties of these laminates are better than those of high-performance thermoplastics and roughly match those of brass and bronze. But unlike these metal options, these high performance thermoset composites will not seize to metal shafts or score them, speeding up bearing replacement and reducing equipment downtime and cost of replacement. With some of the highest load capacities of any bearing material, the composites are specifically designed for heavy load-bearing applications in ships, metal-rolling mills, and off-road construction equipment.