SHAFT SINKING circuit , providing a solution to the age-old problem of incomplete crosshead detachment and release problems ,” Redpath said .
Seeking to further secure the galloway , the company has recently introduced a galloway stage rope monitoring system that detects the slightest changes in loading , inclusive of rope stretch and position within the shaft , Melong said . This ensures the rope factor of safety is not compromised and potential damage to the stage and shaft furnishings is eliminated .
The level of instrumentation and controls used to reduce risks when moving the galloway have also stepped up , with : n The use of variable frequency drives to control speed and position on winch motors ; n Load cells to monitor rope tension ; n Emergency stop buttons on every deck ; n Inclination sensors to measure plumbness ; n Accelerometers to measure vibration and detect impact ; n Optical sensors to measure the distance to the shaft walls ; n Strain gauges on structural members to measure stress and strain ; and n Real-time video footage from dozens of HD cameras . Jeremy Berg , Manager , Engineering & Technical Services at Redpath Canada , said : “ Recently , all of these innovations have been combined to create a safety system designed to
The start of reaming using a Strata 950 raisebore machine for the first leg of a 5.5- m diameter , 470 m long shaft at the Northgate Production Shaft , now owned by Alamos Gold Inc in Matachewan , Ontario
limit the impact energy seen by the galloway structure . This can provide a feasible justification for the reduction of safety factors in the structural design of galloways and work stages in special circumstances .
“ These same systems have also been used by Redpath to safely lower massive structures in the shaft without the need for direct personnel supervision , increasing safety and productivity in these nonroutine shaft activities .”
In addition to wireless communications , the company ’ s patented Integrated Leaky Feeder Mesh system has been installed in two shaft projects in Ontario to improve data transmission . Berg said the company had learned some important lessons regarding installation techniques and environmental considerations to improve future designs .
“ We are currently speaking with another client about using this system in the permanent shaft configuration after we finish the sinking contract ,” he added .
One can add to this list of Redpath
innovations the development of : n The “ shaft bells location identifier ”, which communicates to the hoist operator where the shaft signals ( or bells ) have been rung from , allowing for interlocks which permit hoist movement only when bells are received
Our EPCM solutions can help get your development projects off — and into — the ground .
stantec . com / mining-epcm