In order to provide finer surface finishes and closer tolerances on bar diameters, Centerless Grinding is a process that we at Col-fin offer to our customers. With the Centerless Grinding process, we are able to produce surface finishes as fine as RMS 6, and even finer, if necessary, depending upon size. Our size capacity for centerless ground bars extends from .125” diameter to 2.500” diameter. Tolerances on centerless ground bars can be as close as .0005” total tolerance. Out-of-roundness is critical on any cold-finished steel product, but especially so on centerless ground bars. As a standard part of the centerless grinding process, the bars are inspected using three-point gages to ensure that the material does not include an out-of-roundness condition.
Centerless ground bars are usually cold-drawn prior to grinding to meet customer demands for finished physical properties. Internal structure, hardness and depth of decarburization are critical factors that are considered in the centerless grinding process. Col-fin centerless ground bars are another addition to our premium cold drawn product availability.