Wood Technology: Break Through in Bandmill Control
Recent work at Dunkley Lumber in Prince George, BC, has set a new standard for state-of-the-art feed control in bandmilling. Dunkley is using their Saw Control and an optional “Powerfeed” system to make feed speed decisions on one of their quad bandmills, based on real-time saw performance.
This system monitors the deviation of the saws in the cut and progressively speeds up the feedworks as long as all of the saws are cutting accurately. If any of the saws begins to deviate, the system will instruct the feedworks to slow down. The amount of reaction is proportional: small deviations generate small drops in speed, major deviations cause large, immediate reactions.
The Powerfeed system is run right from the Saw Control main unit and all of the variables are set by the mill. This gives the system the flexibility to work in mills with a variety of different goals in terms of target sizes and production levels. The mill establishes what is acceptable for deviation, then the Powerfeed works to optimize production within those limits.
The basic Saw Control provides information that allows a mill to bulletproof every aspect of saw preparation and bandmill maintenance. The Powerfeed pushes the bandmill to make the most lumber it can while staying on-size.
Excerpts from Wood Technology
Wood Technology April 95