This paper mill had major safety and production concerns in their debarking and chipper room and contacted Overhead Material Handling, Inc. for a solution. There were three safety and production issues:
- The debarking tumblers, long cylindrical tubes used to tumble 6′-0″ logs to remove the bark, often had logs tumble out of the twin de-barkers. The tumbled out logs would become jammed along the conveyor belt and would shut down the debarking process.
- The logs that were too large for the chipper, a large machine with a rotating steel blade which chops the logs into tiny pieces, had to be moved from the conveyor belt to an aisle parallel to the conveyor belt.
- The chipper also required removal of jammed logs.
The recourse for problem one was to manually un-jam the logs with a pick, a very strenuous and dangerous process. Problems two and three utilized a single monorail crane over the chipper In both cases, the single hoist was severely side loaded as it was not positioned properly over either operation and was often pinned to prevent movement along the monorail.
To solve these problems, OMH provided three separate cranes supported by one structural framework tied to the existing building structure. OMH engineers designed and erected a complex framework supporting the three cranes engineered to tie into the almost 100-year old existing building columns.
The first solution utilized a radio controlled 1 ton monorail with a Harrington hoist and motorized trolley running the length of the conveyor in front of the de-barking units. This allowed the operator to run the hoist from the control room and, with the use of picking hooks, lift the logs to remove any blockage.
The second solution was a 2 ton bridge crane with a Harrington hoist and motorized trolley, located over the conveyor allowing the oversize logs to be lifted and moved along the runway to the aisle and lowered for removal.
A third solution was a 3 ton crane with a 3 ton chain hoist on a new monorail positioned directly over the chipper in-feed, which allows the operator to remove logs that become jammed as they are entering the chipper.
All three cranes and their support structure were designed, built and installed by OMH. The project entailed field measurement of the existing structural steel and building foundation, calculating loads on the existing and new steel framework, removal of the unusable existing structural and field fitting the entire system during a one week window in a plant wide shutdown.
All completed on time, and within budget, to keep the disruption to the plant to a minimum. The previous safety concerns to the operators were eliminated and day-to-day system shut downs were reduced dramatically.
Please contact OMH at 1-800-545-5962 or 414-768-9090 and let us help solve your overhead material handling problem.