Levelok®’s Cage Holding System has been providing safe and rapid transfer of workers, material and ore with mine conveyances used in vertical shafts since the 1980s. The Levelok® Cage Holding System consists of a power pack and clamps which hold a cage steady during the transfer of men and/or material. The clamps release their grip at a controlled rate to allow the rope stretch to be taken up smoothly.
An electric power pack is also available.
When the cage is in position, the station air supply quick coupler is connected to the Levelok connection on the cage. The power pack (air/oil intensifier) boosts the hydraulic pressure up to the required pressure. The pump stalls and clamp force is maintained indefinitely. This operation usually takes about 10 seconds for the pump to boost the pressure to full clamping force.
When loading or unloading of the cage is completed, the station air supply is removed, resulting in a rapid loss of air pressure in the power pack. This starts the decompression cycle, which takes about ten seconds. As the oil pressure drops, the clamps release their grip at a controlled rate and the cage slides smoothly to its new position in the shaft. The clamp arms will then fully retract, thus allowing the cage to be moved.
Safe Transfer of men
and material
Time saving, as re-decking of the cage will not be necessary during loading of men and material
Quick and easy to use; single person operation
The system can be complemented with an EFA System
Can be used equally well on steel, rope, rail and wood guides
No Shaft obstruction
Why should I consider using the Levelok Cage System?
What load can the clamps support?
What force is applied to the guides?
What factor of safety is used on the clamps?
How heavy are the clamps and powerpack?
What material are the clamp shoes made of?
What clearance is there between the shoe and the guide?
Can the clamps clamp while the cage is in motion?
How long does it take for the clamps to operate?
How are the clamps fitted to the cage?
Where should the powerpack and accumulator be mounted?
What air or electrical supply is required to operate the system?
What happens if the driver pulls away when the clamps are still clamped?
What happens if a hose fails?
What is delivery time on the complete Levelok Cage System?
The first cage holding system was installed on a cage at Matchless Mine in Windhoek in 1970.