Camlok Props:
- Manufacturing to Underground Operation: Original Equipment Manufacturer – Camlok provides load testing data and quality certification for products delivered on demand.
- End user training on Installation provided by BML Training Department. On the job coaching and visual quality assurance by Team Leader, Miner and Shift Supervisor.
Full Column Grouted tendons:
- Manufacturing to Underground Operation: Original Equipment Manufacturer-Provides quality certification for products delivered on demand.
- End user training on Installation provided by BML Training Department. On the job coaching and visual quality assurance by Team Leader, Miner and Shift Supervisor.
- Post-Installation pull test up to 80KN by external service provider.
- The Service provider will be present on the BML property for 2 shifts every 6 months. The pull test crews will be allocated to obtain a representative sample of tendon installation quality. The findings of the pull tests will be communicated to the respective Mine Overseers via a Technical Report.
Full column grouted tendons should be replaced when:
- Full column grouted tendons are installed at a spacing designed to cater for either a fallout thickness or beam height depending which is of a greater significance. As the hole surrounding the tendon is completely filled with either resin or grout and the required height is catered for by the length of tendon installed, any protrusion as a result of rock dislodging from the collar of the hole will not affect the performance of the tendon in any manner.
- If a tendon is protruding at a length deemed hazardous to people or equipment as it could result in injury due to people walking into the tendon, equipment bumping into the tendon which could loosen surrounding key blocks resulting in a fall of ground, or cause damage to that equipment, the protruding portion of the tendon can be cut off once the immediate surrounding area has been made safe. The remainder of the tendon will still be effective over the remaining length of the tendon as it is glued by the resin/grout to the surrounding rock along the hole length to the height it was designed for.
- If the tendon has been pulled out of the hole as a result of equipment bumping/hooking to the tendon, the bond between the tendon and grout/resin has been broken. In this case the tendon must be replaced as the tendon is no longer effective.
- This will also apply to tendons that have failed the underground post-installation pull test. The failed installation shall be marked and will need to be replaced.
Grout Capsule Cement:
- Capsule Cement will be delivered to the BML store yard. It is critical that the capsule cement be stored in a dry area. Exposure to water may result in the capsules becoming hydrated prematurely which could render the capsules useless.
- Capsules are delivered with best before dates on the packaging. The stock intake and dispatching should take these dates into consideration. A first in first out principle should be followed.
- Sporadic tests will be conducted by the Rock Engineer on stock at the store yard.
- These cement capsules when dispatched to the various shafts should be stored away from possible water exposure. Similarly, the cement capsules should be sent underground on a first-in-first-out principle
Timber elongates (18cm to 20cm Diameter) Supplier to Shaft Storage Yard:
- Timber quality on delivered stock will be conducted on an ad-hoc basis by the Rock Engineer. Timber is delivered on a consignment stock basis. The process flow of ordering, dispatching and
- replenishing stock needs to be well controlled to avoid timber being delivered in oversupply at Shaft storage yards.
- Training of BML timber loading personnel will ensure that sub-specification timber is not dispatched to the Shafts.
- Shaft storage and stock rotation will be aimed at ensuring the timber spend the least amount of time possible being exposed to the elements.
- The timber supplier will be required to conduct yearly compression test on timber. The supplier should in collaboration with Rock Engineer of BML identify and test a representative sample of no less than 5 sticks of each length range.
Sub- Specification Timber:
- Delivered timber to the main storage yard: Diameter of more than 20% of the verification sample is less than the specified 18cm – 20cm diameter range. Timber diameters differ from the 2 ends of the stick. For this reason, the larger diameter will always be measured where possible. This would mean that the smaller diameter would then always fit into the PSU.
- Timber with a crack exceeding 1.0cm in width extending in excess of 1/3 of the length of the timber support unit.
- Timber with an arch where the axis deviates more than 50mm.
- Timber being bulged on the bottom or top extremity of the stick. The bulge would become problematic if the end of the stick cannot fit into the PSU. If the bulge is along one side of the stick only this would mean that the bulge could be cut off.
Osro Straps:
- Manufacturing to Underground Operation: Original Equipment Manufacturer- Manufacturer provides testing data and quality certification for products delivered on demand.
- End user training on Installation provided by BML Training Department. On the job coaching and visual quality assurance by Team Leader, Miner and Shift Supervisor. Generally, the Osro straps are installed by Secondary Support Contractors.