Step #1 Matching ©Dr. B. C. Paul 2000 revised 2008 Note many of the ideas expressed in these slides can be found in Surface Mining Manuals, the Book Surface.

Step #1 Matching

©Dr. B. C. Paul 2000 revised 2008Note many of the ideas expressed in these slides can be found in Surface Mining Manuals, the Book Surface Mining Equipment or

publications by Caterpillar Equipment Company. The Slides contain equipment specifications from the Caterpillar Performance Handbook

and screenshots from the FPC program by Caterpillar Equipment Company.

More Step #1

Make a First Pass with Conceptual - Feel Adjustments to decide where to start

Material Characteristics often favor one type of loader or truck

Mine grades and distances often restrict best truck choice

Sensitivity of organization to capital and operating costs will push toward one machine or another

Example of Conceptual First Pass Match

Quarry Mining Dolomite Heavy lumpy rock

• not a good match for any bottom dump configurations

• Suggests a rear dump truck Quarries usually have steep haul

roads but limited distance• favors a high power to payload• points to Rear Dump Model

Can Usually Match Capital Preference During Conceptual

Phase This is a Quarry Most Quarries Require great equipment

mobility and shifting They maintain bench networks in active

areas They don’t handle fixed infrastructure in

pit well They tend to limit capital investments Suggests a Truck - FEL fleet

Step #1 Gets Quantitative

After Visualization comes three critical Quantitative Checks

#1 Match the Truck to the Material #2 Match the Truck to the Mine

Layout #3 Match the Truck to the Loader

(of visa-versa)

Need to Match Material to Truck

Trucks have both a volume and a weight limit

Consider Komatsu HD785-3• weight limit is 86 tons• volume limit is 69 cubic yards heaped

Dolomite breaks into odd shape chunks that give a lot of air space

Truck Specifications From Manufactures Handbooks

The Meaning of Swell (No it doesn’t always mean things

are great) Tendency of material to break and

pick up air space is called swell• Most materials will have an in place density• Will also have a swelled density• If volume increases 40% say we have 40%

swell• Density Swelled = In Place Density/ 1.4

Don’t get # mixed up

Example of Materials Table from Cat

Matching Material Check the Dolomite against the

Komatsu HD785-3• 2600 lb/Yd3 * 69 yd3 / 2000 lb/ton =

89.7 tons But the Weight Limit is 86 tons

• Truck is weight limited because full volume is hard to use

Can generally overload 5% would allow 90 tons but pushing it

Another Example

Try a Cat 789 for Coal Haulage• Truck is rated for 195 tons• 137 yd3 heaped

Loose Coal is about 1600 lbs/yd3

1600 * 137 / 2000 = 109.6 tons Volume is filled before weight limit

is reached - Volume Limited

Multi-bed Option

Cat 789 can be ordered with a larger bed• 157 yd3 optional bed

1600 * 157 /2000 = 126 tons Still Very Volume Limited Manufactures Often Have special

models optimized to try to balance both - Cat Quarry Trucks are example

Match the Truck to Pit Geometry

Length - Steepness and profile are important• Lot has been done in visualization

In life there is matching of road to vehicles• Spacing - rise and fall• banking or turns and sharpness• Road base

Only Briefly in this Class - too Civil

Checking Turn Sharpness

Terex 3311E 94 ton truck• Wheels have turning radius of 35 feet• Frame has radius of 40 feet• Watch cause manufactures list spec

differently

Tells about switch backs May also be significant in loading

area• May need to pick a loading arrangement and

check the room

Matching Truck and Loader

Three Major Checks• # passes check• loading height check• loader and material Check

Also review compatibility of loading layout and equipment to pit and objectives

# of Passes

# of passes guidelines based on experience with where optimum often lies

Cable Shovels (3 to 4 passes) Hydraulic Shovels (4 or 5 passes) FEL (4 to 6 passes) Backhoes (often 5 to 7 passes)

Go to The Fleet Selection Tab of FPC

I can start out byNaming my firstTrial fleetAnd inputting aDescription

I will then select theAdd Hauler Button

The Select Hauler Screen Comes Up

Program Allows youTo input any machineOr modified machine-Easiest thing is to useCat machines alreadyIn the program

Need to choose whatKind of machine –Hmm – maybe aTruck?

A Wish List of Machines Comes Up

Lets say I’m thinkingA 5 million ton perYear quarry

Guessing Out of the Blue

I want a reasonable number of trucks

I want my production Begin with a cycle time guess

• You know about how far things are and have probably seen a truck drive before

• My silly guess will be 20 minutes

Guestamation Circle

I have 1800 hours per year• At 50 minutes per hour that’s about

1500 hour working time• At 20 minutes per trip that’s about

4500 trips per year If I guess about 85% availability

and 90% utilized of available• About 3450 trips/truck year

Continuing my Guestamation

If I have a 20 minute cycle time and a truck load time around 3 minutes• About six trucks per loader• I’ll guess 6 trucks

6 trucks making 3450 trips each is 20,700 trips

5 million tons over 20,700 trips is• 241 tons• That’s a bit big for a quarry• Maybe 120 ton trucks will be more

reasonable

Things to Notice

Most calculations involve a circle of guessing checking and refining

I want to make a guess at a truck size• I used a rough estimate (which happens to

indicate I knew what calculations would come next)

• Some people compare to existing operations they know

Lets Go Shopping for a Truck

Hows about a Cat785 for about150 tons(click on to highlight)

Then click OK

It Immediately Fills Out the Screen for Me

Filling Out a Couple of Items

I’ll give a startingGuess on the # ofTrucks - 10

I assumed 85%availability

There are other thingsTo fill out but IWill defer them forNow.