Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/945822
AGGREGATES MANAGER / March 2018 25 Check for loose drive belts Inspect screen distribution Look for bottlenecks in the pit Check crusher settings and look for improperly tensioned drive belts. Worn crusher settings will increase feed output size, slowing down the through- put. This is often overlooked and underappreciated, because it can happen gradually in an operation with softer material such as limestone. If one device or an- other "slips" when the feed rate is increased, this is most commonly improper belt tension, worn sheaves, or both. Both are easy fi xes to push the bottleneck into a more desirable part of the operation. Ensure feed distribution of material is spread out across the width of the belt. If material is fed in a narrow stream, some of the available screen area will be lost in the time it takes for the material to spread out. Visually observe for segregated material. If segregation is noticed, examine the defl ector plates to make sure there is a homogenous transfer of mate- rial. Confi rm the chute has been designed to achieve a wide spread across the screen. Determine that the proper screen media is being used. Make sure blasted material is not too large or small. Attempts to save costs or reduce fi nes generation by spreading the shot patterns could result in lump-size material entering the primary circuit and cause a dramatic reduction in overall plant throughput. New bottlenecks — e.g. transfer points bridging with over- sized material — may occur. Offset in blasting costs may be counteracted by the higher cost to produce per hour from lower production rates and downtime experienced. Compare actual plant performance with simulation software to see what the bottleneck should be and if there are issues with crusher set- tings, liner conditions, chamber restrictions, etc. 2 3 4