Coal Sizing System Improves Coal-Handling Performance

Issue 8 and Volume 109.

Equipment wear is prevalent and constant in all coal crushing or sizing operations. Typically, all coal being transported to the silo passes through a crusher or breaker to maintain a consistent and acceptable size. Studies show, however, that 80 percent to 90 percent of the coal being fed through the crusher or breaker is already an acceptable size. This means a lot of coal that does not need crushing is being sent through the crusher or breaker, adding unnecessary wear on the equipment and increasing electricity usage.

To mitigate these problems, Sure Alloy Steel developed the patented SAS Self-Cleaning Coal Sizing Grid system. It is designed to allow maximum material of acceptable size to bypass the crushing operation. This results in much less wear and tear on the crusher components, immediate savings in amperage required to run the crusher motors, and increased feed rate capacity.

Ceramic-lined chutes, like the one pictured here, provide maximum abrasion resistance.
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Recently a major electric utility in the Carolinas upgraded two of its crushers with Sure Alloy’s Self-Cleaning Coal Sizing Grid. Before the upgrade, the crushers couldn’t run at their full capacity of 750 tons per hour (tph) without plugging. They would plug up as frequently as three times per train load of coal, and consume 40 to 60 amps each.

Patented SAS Self-cleaning Coal Sizing Grid with ceramic-lined high-wear areas.
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Sure Alloy engineered two self-cleaning grids along with new high-performance chutes and conveyor skirting. All high-wear areas of the chutes and self-cleaning grids were lined with ceramic tiles for high abrasion resistance. After installing the Sure Alloy Self-Cleaning Bypass Grid systems, each crusher is running at 750 tph, five hours per day, seven days a week without any signs of plugging. The crushers now use only 24 amps instead of the 40 to 60 amps they were using prior to installing the self-cleaning grids. This improvement clearly saves the utility time and money on maintenance, as well as electricity usage.