In the airbag option, when the arm tool is pulled away from the center of the ring, it compresses the air withing the bag, which in turn, by being compressed, exerts the necessary force to press the arm tools into the lug. This force is so great that makes the ring very hard to rotate, and therefore the biggest motor of the machine is used to spin the rotary ring. The ring debarker also has a pair of outfeed rolls to provide support and direct the debarked lugs to the outfeed conveyor, where the finished lugs are carried out of the machine. The outfeed rolls and conveyor are very similar in function and design to their infeed counterparts.
Ring debarkers are high speed sawmill machines, having a linear speed with an order of magnitude of tens of meters per minute, and are very reliable. They are mainly used to debark softwood, with medium to small trunk diameter size. Usually the ring is fixed in one position, but there are also machines with a sliding ring, but with this design the feeding speed gets compromised and therefore is more suitable to use in low to medium speed applications. Some machines can have more than one ring to provide improved bark removal quality, specially when debarking species of trees with a very fibrous bark. In this setup, there is an extra set of rolls between the two rings to provide support. Both rings have independent pressure system and are counter-rotating. This comes with many benefits, such as enhancing the capacity of the ring debarker to provide higher feeding speeds, making it a very high speed ring debarker.
Many advantages are provided by the ring debarker, however, every application is different and a careful analysis must be carried to select the best type of debarking application.