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Show configuration works extremely well for granular material, it creates large blockages when materials such as shredded plastic, clothing, trash, metal, or mud is present in the feed. The removal of the restricting dam while feeding the troublesome material has alleviated the problem. A better long-term solution is the use of an active hopper dam and better classification of shredded material. The conveyor belt was slit for 70 of its 85 feet by a metal shard from a shredded drum when the shard, stuck to the belt with mud, passed under the top-end belt wiper and lodged in the underside rollers. The top-end wiper was repositioned to provide a more positive wiping action. The batch-type weigh scale provides an opportunity for materials to bridge and cause p1uggage. Materials, which are not prepared well by the shredder, (wood slivers, shredded plastic and clothing, and any light fluffy substance) create a feeding problem. This problem can be alleviated by removing or covering internal chute projections with a smooth liner. In the long term, the use of a weigh belt feeder may be a better solution. The ram provides an effective device to deliver feed to the kiln from the batching-type weigh scale. Several types of materials, however, have caused difficulties in ram operation. Long slivers of wood and/or metal have jammed and stopped the ram. Only classifying the feed, to remove oversize materials can eliminate this problem. Finely granulated material will bypass the ram head and collect on the backside thus preventing the ram from fully retracting. A small chain-plug conveyor was installed and timed to convey the bypassed material to the front side of the ram. This solution has worked quite well. o Kiln Bearing Failure The kiln is held in radial position by four rollers (two driven, two idlers). Each radial roller is supported by two pillow block-style bearings which are retained and locked on the roller shafts with Allen-style set screws. Gravity acts to move the tilted kiln in the down slope direction. The kiln axial position is maintained by a single thrust roller (made of soft steel) operating against gravity and the thrust ring. The bearing failure occurred as follows: Over a long period of time the harder thrust ring had produced a groove (approximately 1/4" deep) in the axial roller. Several days after maintenance was performed on the pillow block bearing at the head (upper) end of the kiln, two bearing inner races held by the Allen set screws became loose and worked their way out of the bearing. This allowed the kiln rotating cylinder to drop 3/8". Because the thrust ri ng had worn a groove in the axial thrust roller, an extreme tilting force was applied to the thrust roller as a result of the movement. This in |