Updated: October 11, 2004
   Total Mining Service
   Alimak Raising
   Alimak Slot Raising
   Alimak Mechanised Stoping
Total Mining Service

Australian Contract Mining provides a comprehensive range of specialist underground mining services including:

ALIMAK RAISING
- Ventilation raises
- Stope slot raises
- Ore and waste pass systems
- Raise bore rehabilitation
- Ventilation shafts
- Manway raises
- Emergency ladder way installations

ALIMAK STOPING METHOD
- Mechanised narrow vein Alimak long hole stoping
- Mechanised bulk Alimak long hole stoping

SHAFT SINKING
- Shaft sinking and equipping
- Alimak pilot raising and strip to size
- Shaft rehabilitation
- Exploration bulk sample shafts

MINE DEVELOPMENT
- Decline and level development
- Mechanised stoping
- Airleg and hand held mining
- Diamond drilling
- Shotcreting services

CIVIL CONSTRUCTION PROJECTS
- Hydro-electric projects
- Penstocks
- Surge shafts
- Inspection shafts and airways
- Grouting of water inflows

LABOUR HIRE
- Project Management
- Experienced Supervision
- Experienced Miners
- Qualified Tradesman

Alimak Raising

AUSTRALIAN CONTRACT MINING'S ALIMAK RAISING BENEFITS INCLUDE:

- Fast mobilisation times
- Minimal preparation time
- No restriction on raise angles
- No restriction on raise sizes
- No excessive power demands
- Ideal in any ground conditions or rock types
- No requirement for reinforced concrete foundations
- No “second entry” cost to install ground support or rehabilitation
- Significantly reduced underground excavation costs
- No expensive and time consuming directional drilling required

All this = Lower costs than raise boring methods saving you time and money

Increasing Vertical development productivity underground

Australian Contract Mining is a specialist underground Mining Contractor providing the Vertical development expertise required to drive even the longest, large diameter, vertical or inclined shafts and raises. Using safe and reliable Alimak raising systems, experienced personnel and proven methods, Australian Contract Mining is able to provide real productivity benefits and cost savings to the Underground Mining Industry.

Since 1960 Australia has had a long and successful association with the Alimak raise climber particularly at the Mt Isa Mine using a fleet of 7 climbers during the early major expansion which included a 360m long ventilation pilot raise to surface.

Worldwide more than 2,300 Alimak raise climbers have been distributed, being used to drive more shafts and raises than any other system. Importantly the longest Alimak raise developed to date is more than 1000m in length, meaning no raise is too long or too large for the Alimak raising system and Australian Contract Mining.

Alimak raising provides the safest of all entry methods involving the least risk to the miner and can excavate safely through all types of ground conditions supporting the face after each blast is taken ensuring the integrity of the excavation during all stages of development.

Alimak pilot raise strip and support to
5 metre diameter.

The specialised Alimak Raising methods practiced by Australian Contract Mining can be used for blind raising between two levels or from underground to breakthrough on the surface in all rock types. The Australian Contract Mining Alimak blind raising system ensures fast mobilisation, minimal preparation, is flexible, accurate, economical and very cost effective even over short distances.

Even multiple raises with directional changes in the raise of up to 90° can be carried out easily making this method the ideal choice for ore passes, crusher chambers, split level ventilation raises or any difficult excavation profile.

The Alimak Raising method enables mining approaches, which cannot be carried out using raise borers and has the added advantage of in raise access to allow for the installation of ground support and grouting of water inflows as the raise is excavated, unlike raise boring where boring through highly stressed or bad ground conditions only ends up in ultimate failure or costly and time consuming remediation.

With Australian Contract Mining using our 30 years of Alimak raising experience every raise gets through to its ultimate destination regardless of the ground conditions encountered “first time”, “every time” and “on target” providing the highest practicable levels of safety throughout the entire operation.

Alimak raising consists of four simple steps
[1] Drilling

Drilling is undertaken from the drill deck on top of the raise climber, which is sized to suit the size, shape and angle of the raise.

[2] Loading

When drilling is completed the face is charged with explosives.

[3] Blasting

The Alimak climber is then lowered to the bottom of the raise and into a station for protection before the blast is triggered from a safe location.

[4] Ventilation and Scaling

The Alimak system provides for efficient post blast ventilation and a powerful air/water blast effectively dislodging loose rock from the freshly blasted face making ready for re-entry.

Alimak Slot Raising

The Alimak Slot Raising (ASR) system is specifically designed so that the Alimak climber can be set up in development drives without the cost of a conventional Alimak tail drive.

2m x 2m x 40m long - Alimak slot raise.

The system is particularly suited for excavating stope Slot raises, Escape way raises and Primary and Secondary ventilation raises. The Alimak Slot Raising system has been specially developed to replace Ladder raising, Long Hole raising and Box Hole Boring.

Unlike ladder raising there is no limit to the length of the raise and the ASR system allows the miner to re-enter and travel to the face inside the man cage underneath the safety of the drill deck, scale, drill and charge in a safe working environment and travel back down and initiate the blast - meaning no more ladder raising at your mine.

There is no limit to the height of Alimak slot raises allowing a substantial increase in the height of stopes. 50 metre high stope blocks are simple, easy and cost effective with the ASR system.

The large cross sectional area of the Blind Alimak Slot Raise allows “Top Down” stoping methods and “Single Blast” stope firings.

Remove your need to ever rely on “One Shot Wonders” again and realise the potential of large “Successful” stope blasts using the Alimak Slot Raising system.

The benefits of Alimak raising over raise boring
RAISE BORING ALIMAK RAISING
Expensive directional drilling is required causing significant delay and additional costs with no guarantee of practical completion. Alimak Raising does not require directional drilling due to the high degree of accuracy provided by the mining method.
Where ground conditions are unknown diamond drilling must first be undertaken to determine if the hole can be drilled and will remain open in unstable ground conditions. Confirmation of ground conditions is not required with Alimak Raising. This method can drive accurately and productively through any ground type first time installing ground support as you advance the raise.
Unfavourable ground conditions can cause the loss of valuable rod strings and reaming tools. Alimak Raising is a drill and blast method and does not require expensive drilling consumables.
Cost of reaming significantly increases as harder than expected ground conditions are encountered. The Alimak Raising method is designed to efficiently mine through the hardest of rock types.
Raise drills require massive reinforced concrete foundations to support the raise bore machine which means significant additional costs. Alimak raises do not require concrete collars and Ventilation fans do not require massive concrete foundations.
Raise boring cannot be undertaken at any angle hence additional underground development is required increasing capital development costs. Alimak Raising can be undertaken at any angle reducing underground capital development costs significantly.
Large diameter Raise bored shafts can only be constructed in a straight line. Alimak shafts and raises can be constructed to virtually any angle, shape or size or configuration.
Raise bored shafts often are subject to deterioration due to a lack of ground support. Alimak raises are supported and maintained as the face is advanced.
Alimak Mechanised Stoping
A more cost efficient and productive stoping method

The Alimak Mechanised Stoping (AMS) method provided by Australian Contract Mining is regarded around the world as one of the most cost efficient methods for mining large, narrow vein or even small low tonnage ore bodies. In fact the Alimak Stoping method delivers high levels of productivity allowing otherwise uneconomic ore bodies to become viable.

Alimak stoping has had considerable success overseas first developed in Sweden at the Kiruna Iron Ore mine around 1966 where large stopes in excess of 500,000 tonnes each were excavated. In 1976 the first Alimak stopes were excavated in Canada and it was then introduced into Australia in 1993 with a significant number of projects having already been completed.

This innovative underground mining method allows for fast ore production as access to the stope block is via the Alimak drill raises driven directly on the ore body minimising the costs of nil value waste development. Ore losses and dilution are low compared to other mining methods and the mechanised nature of the stoping operation ensures maximum production, minimising the cost per ton of ore delivered to the mill.

As a guide any large ore body that can be extracted economically using sub level, long hole, open stoping techniques can be mined successfully using Alimak mechanised stoping methods easily breaking over 4,000 tonnes per day with major reductions in over all mine waste development and with significantly less dilution reducing your costs dramatically. Even one metre wide narrow vein ore bodies with short strike lengths and low tonnes per vertical metre can be mined at over 1,000 tonnes per day using the Australian Contract Mining Alimak Stoping method. Alimak Stoping provides greater flexibility when mining complicated and variable ore bodies quickly adapting to suit changes to the ore body widths and angle with the added ability of being able to leave pillars in low-grade or waste.

Alimak Stoping is particularly applicable for mining narrow vein ore bodies currently being mined using hand held mining methods with increased daily production contributing to significantly reduced over all costs and reduced physical fatigue leading to improved safety levels.

AUSTRALIAN CONTRACT MINING'S ALIMAK STOPING BENEFITS:
- Ore bodies can be mined even more profitably
- Can eliminate the need for hand held stoping
- Reduced dilution and increased extraction rates
- Flexibility in following and mining difficult ore bodies
- Development costs are lower