FRESH RESPECT: Consider the Humble Anvil / Counter-Knife!

Although the shaft-mounted ‘teeth’, indexable cutters and inserts receive most of the attention in maintenance routines, it can be a costly mistake to ignore the less obvious partner in the tooling system – the bed-mounted Anvils / Counter-Knives.  Cost-efficient processing with Single-Shaft Shredders & Grinders requires that both halves of the tooling system are intact and free from excessive wear.

The effects of damage to Anvils / Counter-Knives can be drastic, dramatically reducing production volumes, wasting energy, plugging screens, and eventually causing costly damage to bearings and the drive train.   Basically, when Anvils / Counter-Knives are worn, the critical clearances for the shearing action are impeded.  The impact is similar to a loosened screw on a pair of scissors: as the gap increases, the shear decreases.    

When grinding or shredding wood or fibrous materials, the “flex” created by the interrupted shearing action causes deflection, and the material will tend to roll or bend over the worn Anvil / Counter-Knife without being processed.  Thus the screen is plugged longer, material will be re-circulated, and total output volumes will decrease.

To avoid the negative consequences of running with damaged tooling, Cresswood offers the following maintenance “Rule-of-Thumb:”

Change Anvils / Counter-Knives “every-other” Cutter / Insert Change!

Watch Instructional Video on "Replacing and Inspecting Avils and Counterknives" on Youtube