High-capacity cantilevered conveyors are generally found on plant that has a need to luff or slew about a central axis, such as balanced machine stackers and reclaimers. What makes cantilevered conveyors challenging to align is the fact that over their typical range of operation, the structure supporting the conveyor will often experience minor levels of distortion.
Take for example, a standard balanced machine bucket wheel reclaimer boom. When not in operation, the boom will naturally sit with a torsional load under the forward mass of the bucket wheel and drive system. Similarly, the upper and lower members of the boom will experience tension and compression respectively, acting as they are to support mass of the bucket wheel and drive system.
These forces translate into structural strain that elastically deforms both the boom and the conveyor mounted to it, which unless compensated for, may result in the belt running on the conveyor tracking off. While it is quite straightforward to align the conveying components of a conveyor to compensate for this behaviour, it is common for inexperienced technicians to fail to account for the complete operating range of the conveyor. In doing so, they will often create a solution that only works in one position or under very narrow load parameters. IPI have even attended a site to correct conveyor alignments of a bucket wheel reclaimer, where alignments were performed on a conveyor in a maintenance bay, with the mass of the bucket wheel and drive system fully supported. On restart, the belt of the subject conveyor immediately tracked aggressively off. With the strain of the unsupported bucket wheel and drive mass deforming the boom, the “aligned” conveyor was well outside of alignment tolerance.
Key Considerations to Aligning Cantilevered Conveyors
Consider the range of load cases that the conveyor and the structure to which it is mounted will experience during operation
Calculate (or measure) the natural distortion of the conveyor as it is subjected to these load cases
Align based on conveyor load cases, not simply what is true for the state the conveyor is in at the time
Owing to how quickly they can determine critical dimensions, tooling such as the IPI Combination Conveyor Alignment Tool (CCAT) and Shaft Alignment System (SAS) are ideal for setting conveyor component positions on cantilevered conveyors. IPI’s proprietary alignment process also accommodates for increases/decreases in distortion over a conveyor’s complete operating range.
For these reasons, IPI can ensure that your cantilevered conveyor will operate reliably at all times for the lowest possible cost and time investment.
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