Case Study: Replacement guide rope into modified vent shaft with limited access

Requirements: Develop a plan to safely remove existing rope and install new guide rope.  The work was to be performed at an egress shaft which had been modified to act as a primary downcast ventshaft for the mine site.

A detailed procedure was developed in co-operation with site and contractor personnel.  The procedure was prepared to limit exposures and mitigate risks presented by restricted work spaces and limited communications. 

Engineering drawing packages were prepared for rigging fixtures to be installed in the headframe for rope handling.  The fixtures were installed within existing structural constraints created by fan shrouding in the headframe and the limited access to the shaft.

Existing winch equipment was evaluated and tested.  New rope anchors were designed and installed to allow maximum removal of the rope from the drum during moves.

On-site support was provided for all critical phases of the project including development, design, fixture installation and removal and installation of the rope.

Guide Rope Replacement engineering is only part of our available services, check out our other services here:
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Case Study: Replacement of a roller element bearing on the main shaft of a large double drum hoist

Requirements: The bearing inboard of a direct-drive motor on the main shaft of a large hoisting plant experienced premature failure.  A plan was required to remove the large roller element bearing while minimizing downtime on the only production hoist at the mine site. 

A detailed procedure was developed to safely replace the bearing while minimizing interruptions to the operation of the mine site.  The procedure detailed removal of the large 1,000 hp direct drive AC motor stator and rotor as well as lifting the drum assembly to allow removal of the bearing from the housing.

Detailed drawing packages were prepared for fixturing and rigging to lift the motor rotor and hoist drum assembly.  Specialized hydraulic tooling was specified to evenly raise the hoist assembly.  Procedures provided detailed listings of all rigging equipment and specialty tools as well as target values for re-installation of the bearing and other hoist mechanicals. 24-hour on site support was provided during the removal to support heavy lifts and ensure the return of the hoist to safe operating conditions prior to resuming normal operations.

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Case Study: Replacement procedures and fixture design for replacing head ropes at flagship mining installation

Requirements: Development of a procedure to replace the head ropes on three large hoisting plants.  Fixturing and general procedure was to be prepared to maximize commonalities between the three hoist plants.

A detailed procedure was developed within customer requirements to limit exposures and mitigate the risks of handling large ropes.  The procedure included sketches, tooling lists and target values to provide simplified reference during completion of the procedure.

Detailed drawing packages were developed for common handling fixtures (deflection sheaves, rope anchoring) designed for use at all three hoisting plants.  A level winder was designed to control rope spooling on and off of the rope reels. On-site support was provided during installation of the fixturing and completion of the first rope change. 

Rope Handling Procedure Services are only part of our available services, check out others here:
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Case Study: Replacement hydraulic bearing lubrication for plain bearings

Requirements: Replace a hydraulic bearing lubrication system to improve oil distribution and condition monitoring.

The new bearing lubrication system was designed to allow precise flow of oil to each individual bearing housing port and improve distribution across the face of the journal.  Overall oil flow was increased to optimize wedge development and maximize bearing life.  The system provided monitoring of overall oil flow as well as oil flow to each individual bearing port.

The system was custom manufactured on separate containment skids to allow the system to be moved into the basement of the hoist room through existing access hatches.  The tank included control and monitoring of oil temperature, levels and filtration.

Site support was provided during system installation to assist with tube routing, electrical integration into the existing control system as well as during set-up, commissioning and testing.

Hoist Bearing Lubrication Systems are only part of our available services, check out our other services here:
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Case Study:  Addressing Cracks in Hoist Drums

Requirements: Our customer reported that cracks were presenting in their double drum hoist and the customer needed to understand what was causing the cracks and if there were options to address the cracks.

We made a site visit to review the hoist, the drum structure, the existing cracks and to take field measurements.  The field measurements were then used to create an accurate 3D model of the drum for a Finite Element Analysis (FEA) load review.

The results of the FEA allowed us to understand how the structure was loaded which in turn helped us to determine how the cracks in the structure developed.  Additional analysis was completed to see if the existing structure with the cracks was suitable for the existing operational loads.  As previous analysis projects have indicated, it is not out of the ordinary for some cracks in the drum to develop.  It is case by case but sometimes the structure wants to crack to relieve itself and once cracked they do not propagate further.

To confirm the results of the FEA, strain gauge testing was completed on the existing drums.  This allowed us to confirm that the results of the FEA were accurate.

From the testing and analysis, a list of recommendations to address the cracks was presented and reported to site.  Recommendations included practical short-term steps to slow the crack propagation and permanent long term solutions to address the problem.

Hoist Drum FEA’s are only part of our available services, check out our other services here:
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Case Study: Add pinion brake to existing double drum service hoist

Requirements: The site was wanting to perform single drum man travel during emergencies. The hoist was a double drum hoist with a single motor and was not equipped with a pinion brake. A pinion brake needed to be added to the existing hoist without affecting the current hoist/motor locations. This pinion brake would ensure that two brakes were always available during single drum operation.

A pinion brake coupling was designed to replace the existing motor coupling. Calipers were fitted to custom designed stands which allowed for mounting between the existing hoist motor and bull gear.

Due to space limitations a specially design pump unit was supplied that allowed for mount in the available space.

Pinion Brake Add-on’s are only part of our available services, check out our other services here:
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Case Study: Apply a new hoist control, safety controller and brake regulator to an existing hoist

Requirements: Design and supply an upgrade to the existing hoisting plant requiring new hoist control, electronic Lilly, brake regulator and new operator interface HMI. The hoist control needed to be integrated with an existing AC wound rotor control for service duty.

The hoist control panel, Safety Cube and brake regulator panels were integrated into one panel group to minimize on‐site wiring and to meet the limited space available.

The new console included two large touch‐screen monitors for increased functionality and ease of operation.

A maintenance computer was provided with long term data logging as well as diagnostic software with detailed troubleshooting capabilities.

Mine Hoist Control Systems are only part of our available services, check out our other services here:
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Case Study: Incorporate an upgraded brake and hoist control into an existing hoist

Requirements: Design and supply an upgrade to the existing hoisting plant requiring new hoist control, electronic Lilly, brake control with new hydraulic supply and a new operator’s console. The hoist control needed to be integrated with an existing AC wound rotor control for automatic skipping.

The hoist control panel and the new Safety Cube panels were integrated into one panel group to minimize on-site wiring and to meet the limited space available.

The new hydraulic supply incorporated submersible pumps to satisfy a reduced footprint and also provided quieter operation – filtration, temperature control and system monitoring was improved.

The new console included two large touch-screen monitors for increased functionality and ease of operation.

Mine Hoist Control Systems are only part of our available services, check out our other services here:
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Case Study: Replacement of MG Set with New Drive and Hoist Control

Requirements: Outdated technology replaced and upgraded to an existing hoist ‐ limited time for change over and limited space, motor needed to be sent out for refurbish during the shutdown.

A new digital drive was engineered and specified for the duty requirements. To satisfy the limited space and shutdown constraints, a mezzanine was constructed above the existing power and control cabinets and the new installation was completed and pre‐commissioned, ready for a quick switchover from old to new. Downtime for the change, including final commissioning was less than two weeks, during which the hoist motor was removed and sent out for refurbish (4 days).

New Mine Hoist Drive and Control Systems are only part of our available services, check out our other services here:
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