MINING MACHINE DEVELOPMENT PROPOSAL - Reef Mole Mining ...reefmole.com/images/AGA_Project_Proposal_clean.pdf · Improvements in excavation and availability rate of ... mining and

AGA

Anglo Platinum Project Proposal 1

MINING MACHINE DEVELOPMENT

PROPOSAL

Prepared for:

Prepared by: John Gibson, partner, AG Associates and

Llewellen Anderson, partner, AG Associates

Anderson Gibson Associates

4840 NE 40th

Street, Seattle, WA, USA, 98105

[email protected] , +1 541 398 1713


December 21, 2010 Proposal number: RCTS 2010-101

TECHNO

LOGY

SERVIC

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mailto:[email protected]


AGA


Executive Summary

Objective

The proposal projects will produce designs for an enlarged production RM and a

larger RM for excavating strike gullies. The ‘extra’ projects are normal steps in the

product development and will improve the efficiency and availability of the RM

family of machines.

Goals

Completion of detail design of an RM 1200 and an RM 2000 or RM 2000 XP.

Manufacturing cost estimates, operating costs and production rates will be

completed and benefits to the mine identified.

Improvements in excavation and availability rate of Reef Mole style machines by

testing of typical Platinum mine rocks, testing of alternate cutter types and design

studies of alternative power and vacuum systems.

Solution

AGA and it's associated companies in South Africa will assign qualified personnel to

carry out the identified tasks according to the project schedule and budget. The

projects may be completed in any sequence.

Major Project Milestones

Completion of design layouts and analysis for an RM type machine that cuts a1200

x 5000 mm opening including cost of manufacture and performance estimates

Completion of design layouts and analysis for an RM type machine that cuts a 2000

x 4000 mm opening including cost of manufacture and performance estimates

Discussion of machines for large openings

Coordination with test results from RM 950 excavation at Waterval mine

Collection and lab testing of representative rock types and summary of existing test

results

Preliminary design of alternate power and vacuum systems to better match mine

safety and environmental conditions

Additional studies of alternate RM system designs

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Contents

1. Project description, machine series, technical basis of design, development and

manufacturing

2. RCTS organization and associated companies

3. Experience, RM 850, RM 950, VM 800

4. Stope mining machine, RM 1200

5. Gulley development machine, RM 2000, RM 2000XP

6. Main Shaft development machine

7. Additional tests and design studies of rock types, power/control and vacuum systems

8. Project Plan

9. Project Schedules and cost estimates

10. Project total cost estimate for engineering, travel and testing

11. Reference Information,

rock energy density graph, cutter spacing/penetration ratio graph, rolling cutter technology,

typical tunnel boring machines, size, weight, power and cost table, historical machine types,

& Web links

AGA


1. Project description

The primary goal of the project is to produce rugged machines manufactured in

South Africa that excavate the ore and the gullies found in the narrow reef

platinum mines.

This proposal describes the next phase of product development for the original Reef Mole

type machine. From this machine a family of machines suited to needs of Anglo Platinum will be

designed and developed.

Besides the structural design of the machines the proposal identifies several technical aspects

of the systems that would benefit from additional testing, specification or standards evaluation.

Descriptions for these programs, their schedules and costs follow.

The Reef Mole is designed and manufactured to the same standards as those

tunneling and raise boring machines that are used so successfully throughout the

mining and civil construction industries. All of the steel fabrication, hydraulic

and electrical design and manufacturing and assembly skills are found in local

industry.

RM production rates were estimated on a kW-hr / tone basis. Analysis of

penetration, thrust and boom swing rate results in production of ore and

determines the loads used to design the structural components.

These values fit with the ‘standards’ established from testing and performance from actual

tunneling projects. Testing of the RM 850 at Townlands mine confirmed the estimated values

and power consumption for the UG2 and surrounding rocks. See Reference 11.1.

Cutter wear for the testing was very small and analysis showed that the projected life of

cutters was comparable to expectations for roller cutters used in the tunneling and mining

industries.

The Patented Reef Mole machine concept brings together certain elements of

mechanical design in an excavating machine which results in an opening ideal

for narrow reef mining.

First, the opening produced has a flat footwall and hanging wall.

Secondly, it uses standard tungsten carbide inserted roller cutters that cut the reef and

surrounding rocks very easily and resist the abrasive material well.

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Thirdly, the use of hydraulic cylinders as the main power source on the machine to drive

the cutters through the rock means that the large forces for thrust and rolling are provided by a

strong element that can fit into the small opening. No gearboxes or electric motors are used on

the machine itself.

Fourthly, the RM configuration lends itself to mounting on tracks for mobility.

Particularly in a gulley size excavator where it would need to be moved to different locations.

And lastly, the rock cuttings are small and easily handled by a vacuum system, no

primary crushing is needed and the amount of waste rock produced is significantly reduced.

There will be many benefits realized from the cleanly cut footwall and hanging wall related to

rock support and equipment maintenance. Full day operation is possible and conditions will be

safer for personnel.

The following diagram shows the RM 950. Note the Front Gripper, sliding Rear Grippers,

Swing Cylinders, Swinging Boom, Cutter Head and Vacuum Shroud on the cutter head.

RM 950 narrow reef mining machine

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2. Rock Cutting Technology Service - RCTS

RCTS is a South African registered company. The four partners

bring years of experience in the design and manufacture of heavy

excavation equipment.

For many years, Mr. Anderson and Mr. Gibson were employed at a major manufacturer

of tunneling and mining equipment and have management, project engineering and underground

experience. This was during the formative years when the design and operation of tunneling and

raise boring machines matured and mechanization became standard in those industries. This

included participation in the development of new machine types such as the mobile miner and

box holers. The Reef Mole is covered under a South African patent held by their company

AG Associates, Seattle, Washington, USA. [email protected] , +1 541 398 1713 or


The goal of AGA is to be a technology company based in the USA. To form

partnerships with in-market companies to design and build excavation

equipment specifically for the production, safety and environmental needs of

narrow reef mines and to provide local aftermarket service and parts.

These machines will excavate the reefs and the openings for access and conveyance using

proven roller cutter technology. With the exception of a few specialty items like bearings, the

machines and cutters will be totally manufactured in-country by associated engineering and

manufacturing companies.

The original RM 850 and the rebuilt RM 950 were designed and manufactured

by AG &Associates (Seattle, USA), Scheffer Mechanical Technology (Witbank),

Megmet Engineering (Pretoria), Turnkey Hydraulics (Wadeville), Orbweb

Electrical/Electronics (Pretoria) and several hydraulic cylinder manufacturers.



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3. "On the ground" Experience

Besides the work experience described above, work on the RM projects has

involved design, testing, redesign and manufacture of the RM series of

machines.

This includes the RM 850, the RM 950 and the VM 800 which was built and tested in

Canada.

Our partnership in South Africa, RCTS and associated companies have persisted in solving

the problems encountered and found solutions which have been incorporated into the RM 950. It

is to begin testing at a mine near Rustenburg, SA in January 2012.

The RM 950 has been strengthened in the gripper and steering systems and equipped with

larger cutters to increase the opening size to 950 mm x 5000 mm. A test and panel excavation

plan is being developed with the mine. Operation of the machine during this project can allow

for incorporation of new information into the design of the next machines in the family.

The RM 950 is predicted to mine at a rate of 1 meter per hour and can operate at

least 10 hours or more each day if the operating crew is properly set up to sustain

the logistics of operation.

Each meter excavated yields about 18 tonnes of rock.

If the reef is 300 mm width then the dilution in a 950 mm cut is roughly 2 to 1. This

compares very favorably to an excavation width of 1800 mm, where the dilution is 5 to 1. This

means that if all the ore in a mine was produced mechanically then a monthly quota of

platinum would be produced by processing 1/2 the volume of material and with no primary

crushing.

Original testing of the RM 850 took place at Townlands mine in the same area.

Having to access the machine by vertical shaft and coordinate with blasting was very

limiting to the time the operating crew was able to spend on the machine. Operating crews

have to develop a strict regimen to coordinate the attention needed by the systems. Machines are

dependent on mine power supplies which can be unreliable. Servicing and repair of the machine

was difficult. Also, installation and removal of the machine was very difficult, time consuming

and expensive.

Manufacturing abnormalities encountered during testing demonstrated the importance of

strict quality control in materials and processes.

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Loading higher than the design loads proved too difficult for the machine

components to be operated at maximum capacity.

Most of the excavation was carried out at 60% of thrust and power capacity. Nevertheless,

reliability, advance rates and cutter life predictions were very favorable.

Roller cutters have been used in various rock types for years.

They work by pressing against a rock with great force and crushing the rock that they are

directly in contact with. The amounted penetrated is proportional to the load or thrust

applied. This action creates lateral tension cracks which want to propagate to the adjacent kerf

if it is close enough. You can imagine the variables related to rock strength, toughness, existing

cracks, cutter force, tip sharpness and even overburden stresses in some cases. In addition, the

cutter has to be forced through the rock as a boat through water. If you roll the cutter faster it

takes a greater amount of power. A certain amount of broken rock is yielded by this process

depending on the depth of penetration and the speed of rolling.

So much roller cutter testing has been done that there are standard charts for 'energy

density' and spacing to penetration ratios for roller type cutters. Examples of these charts

have been included in the 'References' section.

During testing of the RM 850, it was determined that the machine operated at a

level of 13 to 20 kW-hrs/tonne of rock excavated.

This level was significantly reduced with a new cutter design during testing. Some of the

testing proposed involves alternate cutter designs which can result in more efficient cutting so

that more tonnes are produced by each kilowatt of power used.

Factors related to penetration and power determine the specifications for a specific

machine and from them an estimate of performance or production can be calculated. From

the design forces and rates of operation the machine structure and energy systems can be

designed.

The most efficient performance has been found to occur when the spacing to penetration

ratio is approximately 20. The insert row spacing on the cutters averages 25 mm and the

design penetration rate is 2.0 to 3.0 mm per pass of the cutter head. The design cycle time for the

boom swing is 6 to 10 seconds.

The new RM 950 has been analyzed and designed for sustained daily operation at

these load and power levels. New machines in the RM family will continue to

improve based on the testing and analysis of the RM 950 during the coming year.

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In addition, the mine will develop the crew and support systems needed for the

machines to operate at a high utilization rate. These will include guidance and

rock bolting systems.

The following diagrams show how a typical mine area panel development using these

machines might look.

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Overall view of an inclined shaft and developed R & P panels

RM 950 developed R & P panel development

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Starting ‘Cubby’ for the RM 950

View of the Vacuum pumps, ore drop boxes and electrical panels

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4. Panel Mining machine, RM 1200

This machine would be a more powerful version of the RM 950. It would cut an

opening of 1200 mm X 5000 mm.

Additional cutters would be installed and the power and thrust increased so that the

excavation rate was the same as the RM 950.

This additional width is for the reef formation at Waterval mine.

The reef there has a thin seam of rock directly above it that is approximately 150 mm thick. It

is desirable to remove this layer with the machine but in doing so with a 950 mm machine some

portions of the lower reef are left behind. Cutting a wider opening recovers more ore with the

disadvantage of increasing dilution. It is most efficient to keep the machine cutting ahead rather

than trying the difficult and time consuming maneuver of undercutting the footwall in small

areas.

The layout, detail design and structural analysis of the machine will be completed to

include detail drawings to in-country standards. A price estimate for the machine

based on manufacturer’s quotations will also be provided.

A specification sheet for the proposed machine is shown on the next two pages.

The milestones, schedule and cost estimate for this project are given in Sections 8 & 9.

AGA


Reef Mining Machine RM1200

Condensed Specifications (Preliminary) December 13, 2010

Cutter Head: Cutting Height 1220 mm (48”) cut height

Gripper: Hydraulic actuated cylinders, 2 sets of 2, gripping

between hanging wall and foot wall

Gripping Force 222 kn. (50 000 lbs.) each

Rock Contact Pressure 22 bar (320 psi)

Cutters: Number 8

Type Multi-row with Tungsten Carbide inserts

Diameter 382 mm (15 ins)

Insert Spacing 33 - 37 mm (1.3 – 1.5 ins)

Rated Capacity 267 kN (60 000 lbs)

Swinging Boom:

Maximum Extended Length 2 500 mm (78.7 ins)

Extension 500 mm (19.7 ins)

Thrust Capability 2 224 kn. (500 000 lb.)

Swing Velocity 0 - 76 m/min (0 – 250 ft/min)

Angle of Swing 200 degrees

Support Frame: Length Approximately 2 500 mm (98 ins)

Width Approximately 2 500 mm (98 ins)

Pivot Sealed tapered roller bearings in EP grease

Main Gripper: Hydraulic actuated cylinder gripping between

hanging wall and foot wall.

Gripping Force 2 000 kn. (450 000 lbs.)

Rock Contact Pressure 172.5 bar (2 500 psi)

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Gripper Carriage:

Rear Grippers: Two pairs of hydraulic actuated cylinders gripping

against hanging wall footwall.

Gripping Force 1 112 kn. (250 000 lbs.) each


Steering and stabilizing: Pitch and roll steering is accomplished by

varying oil flow to the four rear gripper cylinders

thereby moving the support frame and boom in

whichever direction is required, pivoting about the

main gripper spherical mount. All cylinders are

fitted with linear transducers

Muck Removal:

From Face Vacuum system via suction nozzles strategically

mounted on the cutterhead.

From Machine Vacuum hose and rigid pipe that transfers the

cuttings, dust and fines to a water scrubber to

remove dust before discharging the coarser material

onto the mine conveying system

Power Pack:

Electric Motors Water cooled, double ended shaft. Total installed

power: 350 kW (470 hp)

Oil Pumps – swing cylinders High pressure, 345 bar (5 000 psi), high volume,

0 – 1 320 lit/min (350 gpm) variable displacement

pumps for boom swing and fast regrip.

– thrust cylinders Medium pressure, 104 bar (1 500 psi), low volume,

0 – 136 lit/min (36 gpm) variable displacement

pumps for thrust, gripper and steering control.

Required Services:

AC Electrical Power 420 kVA, 550 V, 50 Hz

Water for Oil Cooling 226 lit/min @ 7 bar (60 gpm @ 100 psi)

Ventilation Adequate flow across the stope face.

Weights: RM1200 assembly Approx. 22 Tonnes (48 000 lbs)

Power pack assembly Approx. 8 Tonnes (18 000 lbs)

Vacuum unit assembly Approx. 5 Tonnes (11 000 lbs).

Maximum modular component Approx. 8 Tonnes (18 000 lbs).

AGA


5. Gulley Mining machines, RM 2000/2000XP

Two versions of this machine would be evaluated. They would cut an opening of

2000 mm X 4500/5000 mm.

The first version would have the same power as the RM 950.

The design excavation rate would be 1/2 M/hr. The power unit would be very similar to the

RM 950 unit. This machine would have an indexing cutter head with 6 cutters. It would require

2 swings to cut the full face area. It would be lighter and less expensive than a full power

version and would yield 5 Meters of advance in a 10 hour operating day. This may be adequate

for some mining plans. It would be mounted on tracks so it could be moved to other

locations.

The second version of this machine would have a design advance rate of 1 meter

per hour.

Additional cutters would be installed and the power and thrust increased to match the design

loading. The power unit would require higher power motors and a larger oil reservoir. It would

be mounted on tracks.

The layout, detail design and structural analysis of the machines will be completed

to include detail drawings to South African standards. A cost estimate based on

manufacturer’s quotations will also be provided.

Specification sheets for the proposed machines are shown on the next 4 pages.

The milestones, schedule and cost estimate for this project are given in Sections 8, 9 and 10.

AGA


Strike Gulley Machine RM2000

Condensed Specifications (Preliminary) December 12, 2010

Cutter Head: Cutting Height 2 010 mm (6’ 7”) cut height





Cutters: Number 7





Swinging Boom:













Gripper Carriage:








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Muck Removal:







Power Pack:



Oil Pumps – swing cylinders High pressure, 345 bar (5 000 psi), high volume,






Required Services:




Weights: RM2000 assembly Approx. 14 Tonnes (32 000 lbs)




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Strike Gulley Machine RM2000XP

Condensed Specifications December 12, 2010

Cutter Head: Cutting Height 2 010 mm (6’ 7”) cut height





Cutters: Number 12





Swinging Boom:













Gripper Carriage:








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Muck Removal:







Power Pack:



Oil Pumps – swing cylinders High pressure, 345 bar (5 000 psi), high volume, 0

– 2 000 lit/min (530 gpm) variable displacement





Required Services:




Weights: RM2000XP assembly Approx. 30 Tonnes (66 000 lbs)




AGA


6. Main Shaft Mining Machine

Earlier, the advantages to narrow reef mining of the patented RM concept were

explained. In the large sizes of either inclined or vertical shafts the full face

machine types have been developed to do just this kind of work.

There are several companies which have built and tested these kinds of machines. See the

reference section web links for information on these.

For these reasons no work is being proposed to develop a machine larger than the

gulley excavation machine.

There are advantages to a partial face machine where the geology requires access to the face

for ground or water control.

An available option is to make two cuts with a smaller machine.

First a face would be advanced a certain distance and then the lower face would be advanced.

The design challenge in this is to provide an adequate gripping system for the machine when it is

removing the lower face. A ‘floating’ hang wall would be designed. This might also be used as a

starting ‘cubby’ for the production RMs.

The overall advance rate would be less than for a full face machine but the performance may

fit into a particular project.

If this is the case, AGA would perform a design study to further define an

approach to a system and make a proposal. Contact any of the listed AGA

representatives.

AGA


7. Evaluation of additional tests or alternative designs

Certain areas of the RM system may yield better efficiency or cost reduction if

more were known about them or alternative approaches evaluated.

4 practical and current examples of these issues are:

Increase in production with a new insert pattern on the cutters. This was found in the RM 850

testing at Townlands mine. All current cutters are to this design.

A question has arisen as to whether the computer control hardware is adequately protected by

their enclosure and whether they should not be separate from the machine power unit. How

would they be remotely mounted?

When the machine is hidden away in it's excavation, what method is going to be used to enable

the operator to steer the machine so that it maximizes ore recovery?

A list of topics have been identified and study projects defined for each. Some of these are

only paper studies and others include designing, building and testing hardware. Individual cases

will be evaluated for their particular parameters. In all cases a report will be completed and

action recommended.

The following is the list of items. Their schedules, goals and costs are shown in

Sections 9 and 10.

Rock test results - Identify and collect all existing test data from prior testing of the

Waterval mine rock types. Compile results and predict RM performance.

Rock Testing. Alternate to 1. Collect suitable size samples from all rock types present

to do physical characteristic tests (200 mm ^ 3) and roller cutter tests ( 500 x 500 x 1000

mm). Contact and select a suitable test lab and contract for testing. Use cutters from the

RM 850 testing which include insert and integral disc designs. Design, manufacture and

test a wider spaced integral disc design. Evaluate test results and make recommendations

for RM and cutter designs.

Electronics cabinet design - Identify alternate classifications of electronic cabinet

environmental designs, compare to existing RM standards and identify practical

communication methods and more secure alternate locations for the electronic

equipment. Make recommendations for new designs.

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Machine guidance systems - Work with Waterval mine staff to develop a practical

position reference system so that the machine operator can remotely. Recommend a 'best'

approach and provide a set of specifications and costs.

Machine Communications - Identify a practical system for audio and visual

communication between the operator station and crew when they are in the area of the

machine. Recommend a system and provide specifications and costs.

High intensity power systems - Provide a practical design with specifications, costs

and advantages for a higher voltage electrical system and a higher pressure hydraulic

system that would yield improvements in efficiency or reduce weight and costs for RM

style machines.

Hydraulic reservoir study - Through testing on the RM 950, evaluate the performance

of the hydraulic oil reservoir. Identify alternative methods to cool and de-froth the oil.

Provide system specifications and costs with recommendations for reducing the volume

of oil held in the reservoir. This will yield a smaller power unit and make it easier to

handle.

Remote power unit study - Evaluate and design an oil transfer system which would

allow the power unit to remain in a gulley. Design a mining pattern which could be

accomplished with this system that satisfies the mine's requirements for support,

ventilation and safety. Provide defining documentation, specifications and costs for the

system.

Vacuum system evaluation - The vacuum system currently in use on the RM 950 will

be evaluated when in place underground to test it's capacity limits for length of

conveyance, air volume moved and volume of transported material. The factors

determining it's medium term maintenance and support will be identified and

improvements recommended. A list of alternate equipment types, hardware suppliers and

alternate types of units will be provided.

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8. Overall Project Plan and Schedule

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9. Project Schedules and costs

9.1 Project Management Schedule

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9.2 RM 1200 Design Schedule

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9.3 RM 2000 Design Schedule

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9.4 RM 2000XP Design Schedule

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9.5 Extra Studies for operational improvements

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10. Project Total Cost Estimate

10.1 Summary and Total Estimated Expenses

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11. Reference material and Web links

11.1 Graph of excavation power required to particle size, Ref: Colorado

School of Mines

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11.2 Graph showing the relative power consumption for roller type

cutters for various spacing to penetration ratios.

11.3 For information related to roller cutter technology, see the web

links listed below for the different types and their applications.

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11.4 Graphs showing specific characteristics of a range of excavation

machines.

The following graphs show established value trends for measured

values of the rock breaking parameters relating energy and the size of

the broken material.

They point out the position of the Reef Mole 850 test values in the

overall data set and of the average values for tunnel boring machines.

Graph 1 illustrates the band of values as a function of particle size.

The differences in the high and low values relate to the rock toughness

and compressive strength. This graph also shows values from the RM

850 testing at Townlands Mine.

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Graph 2 illustrates the values plotted from the data covering

manycompleted tunnel projects. The important factors to compare are

kW/cutter, cutter spacing in MM, the specific energy in kW-hr/tonne

of excavated rock, and the penetration per pass.

The RM 950 values are shown for comparison. Because of the use of

inserted cutters which are long lived and have a close spacing the effect

is to reduce the penetration per pass for a given cutter thrust force and

to require relatively more power for each cutter. Ie, the cutter rolling

force ratio is higher and the speed of rolling must increase to have an

economical production rate.

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11.5 For historical excavation machine types see the web link listed

below.

11.6 Web Links

See this on-line paper for a broad look at excavation technologies for

many types of machines.

http://cerena.ist.utl.pt/masysnet/books/SMEMiningEngineeringHandbook/2

2%20Section%2022%20Novel%20and%20Innovative%20Mining%20Methods

/C22_1.PDF

This site shows some very interesting mining and tunneling projects

http://www.oobject.com/category/20-interesting-boring-machines/

http://www.platinum.org.za/Pt2008/Papers/293-296_Harrison.pdf

http://www.patersoncooke.com/system_app/underground/UNDERG_hoisting.pdf

These are good industry websites for general and specific information.

http://www.tunnelingonline.com

http://www.world-tunnelling.com

These are academic references.

http://www.saimm.co.za

http://www.canadianinstitute.com/mining.htm

http:// www.mines.edu

And search Google or Bing with any of these terms to discover more

information.

Tunnel machine roller cutters, tunnel boring machines, raise boring

machines, tunnel projects, Chicago deep tunnel project, tunnel machine

guidance systems, rock tunneling

http://cerena.ist.utl.pt/masysnet/books/SMEMiningEngineeringHandbook/22%20Section%2022%20Novel%20and%20Innovative%20Mining%20Methods/C22_1.PDF



http://www.oobject.com/category/20-interesting-boring-machines/

http://www.platinum.org.za/Pt2008/Papers/293-296_Harrison.pdf

http://www.patersoncooke.com/system_app/underground/UNDERG_hoisting.pdf

http://www.tunnelingonline.com/

http://www.world-tunnelling.com/

http://www.saimm.co.za/

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MINING MACHINE DEVELOPMENT PROPOSAL - Reef Mole Mining ...reefmole.com/images/AGA_Project_Proposal_clean.pdf · Improvements in excavation and availability rate of ... mining and