KnifeSol rubber bonded steel spacers have the same tolerances (flatness and parallelism) like circular knives. We believe that the spacer should have the same hardness at core as the knives’. The steel ring is usually produced in 9CrSi material, hardened at core with same hardness of circular knives’, especially, to maintain the same feature on the shaft. More and more the tools (Knives, spacers, rubber bonded steel spacers) are mounted and fixed on the shaft with a very high tightening load. The spacers must therefore resist these loads. But the most obvious reason is that the spacers have to resist for long time, so we also consider the possibility of an incorrect handling due by the workers that could easily damage the spacer, if they were not hardened at core.
KnifeSol use two type of rubber, BunaN/Perbunan and Polyurethane. The choice of rubber type depends only to your processed material. We will suggest you the right rubber for your process rules.