INTRODUCTION: Powell Industries in Waynesville, North Carolina has built and installed a protective cage surrounding a portion of the chipper infeed at its sawmill. This cage improves the safety of the chipping operation.

GENERAL FEATURES: The cage is approximately 4 feet high, 3-1/2 feet wide, and 3 feet long. The cage's frame is made from 3-inch-diameter round metal pipe. Expanded metal from old chipper screens covers the two sides and the top of the cage. Rubber strips from an old conveyor belt are attached to the top of the cage and over the front opening where the wood slabs feed into the chipper. The cage is not fastened to the floor, so it can be moved when maintenance is needed on the chipper.

APPLICATION: It is normal for slabs and wood scraps to be deflected and occasionally hurled backwards or sideways when they come in contact with the chipper disc and knives. This protective cage keeps any "bounce-back" from traveling very far and potentially injuring a mill worker; it is an inexpensive safety enhancer. The cage also reduces the temptation for the chipper operator to reach in to unplug a jam or handle slabs close to the chipper (which no one should ever do anyway, unless the machine is locked out and tagged out).

Fig. 1: Protective cage over chipper infeed.