Challenge

Underground mine operations have serious logistic and cost issues related with taking production buckets underground when the size of the unit exceeds the cage dimension. These bucket change outs necessitated the frequent use of valuable shaft time and required additional manpower to remove the bail and sling equipment down to desire level in the mine. Getting cores to surface could only be done with long term planning and only at certain times of the month. Ramp or decline operations spend time bringing LHD to surface for bucket change out due to localized wear in lip and heel area. The mine shaft was occupied by taking bucket down in parts and thereby displacing production.

Engineered Solution

Development of a heavy duty mechanical bucket with replaceable wear components was developed in order to address several concerns. Focus was placed in high wear areas such as lips fronts, the basket area of the bucket as well as the spill guard assembly of the bucket. These components could now be produced independently from the back end bucket and mechanically attached in a fraction of the time when required based on wear of the unit. Further designs have been developed to ease the logistical transportation of these critical components in the mine using their existing infrastructure. This mechanical concept now allows the mine to quickly load the equipment for transportation without slinging equipment down the shaft. A complete change out of mechanical components can now be performed by mechanic within 6 hours at the face.

Rebuild Time vs Welded Bucket

• Bolting system allows for bucket to be attached mechanically in about 6 hours

• By comparison welding time would require about 22 hours or a savings of 16 hours

• No welders are required

• Without bolting system bucket would have to be cut and clipped into various pieces

Logostic Savings

• With mechanical system all change outs and spare parts can be stored underground

• With a decline/ramp system - no need to bring bucket to surface

• With a shaft system - logistics savings include:

• Customized design allows for bucket to go underground in one piece

• Reduces need to pull the cage

Operations and Capital Savings

• Mechanical system means longer bucket life and therefore lower operating costs as designs matches wear wear patterns of the operation

• All worn components can be changed out within one shift underground as opposed to being sent to surface and back

• Number of spare buckets is reduced due to spare parts being stored underground

• Capital expenditure on spare buckets reduced