Steps in Fleet Selection

©Dr. B. C. Paul 2000, revised 2008Note- General steps and methodologies found in these slides roughly

follow material found in Surface Mining manuals by SME and literature published by Caterpillar Equipment Co.

This presentation includes screen shots from the FPC program compiled by Caterpillar Equipment Company.

Sizing Truck and Loader Fleets

30 years ago would have been all manual methods

Today have computer aided versions of same manual methods

Also have versions that consider event probabilities

Full computer simulation

Class Approach

Will show features of manual methods• Features still drive most computer

aided methods Then show applications of

computer software• Things still need to be dealt with in

full computer simulations

A Software Package(Caterpillar’s FPC)

Starting FPC

Of course can alsoBe done from aDesktop icon

After a Picture of a Truck We Get the Initial Screen

Highlight File and Pull Down the Menu

Pick New(for NewProject)

FPC Opens With the Project Tab Active

I start out entering a1- Job Name2- Job Description3- Prepared For4- Prepared By5- Study Date

I Must Pick My Unit and Display Standards

Pick Metric orEnglish Units with aRadio Button

Pick productionTargets measured inWeight or volume

Pick Decimal Format

Pick Currency

Pick Project Specific Information

Enter Your Fuel CostFor Diesel

Enter Your PlanningTime unit

Enter Your NumberOf hours per planningunit

Commentary

Diesel Fuel Costs• Often mine machinery is run off

highway so there is no highway tax on diesel (no 46 cents and usually bought on bulk contract)

• Called “Red Dog” because sometimes put a dye in it (so you’ll get busted for on highway use)

Most planning units are by the year

Specialty Items Needed

“Shift Efficiency” – how much of the scheduled time is actually spent working equipment• An average is 50 minutes/hour or about 83-84%

Operator Efficiency• Truck is capable of certain performance – often not

realized by human operators• According to caterpillar studies operators approach

mechanical limits more closely as haul gets longer• By picking operator efficiency by Haul distance the

program will use caterpillars operator studies results

A Bunch of What?

Problem of Bunching• If have a lot of trucks they tend to arrive in

clusters rather than evenly spread• Means loaders will loose some time with no

trucks and trucks will wait in line even when perfectly matched

• Caterpillar’s studies and bunching factors can be used by selecting average bunching.

Finish the Fill In

I’m putting in 84%For my shiftEfficiency

I’m calling forAverage bunching

I’m having operatorEfficiency estimatedBy haul distance

Optimizing?

Try several different fleets Get Cost of Each Fleet Pick the Fleet with the lowest cost

that you have confidence in• Usually there are some assumption or

preferences that you will not just pick the cheapest

Main Steps in Fleet Selection

Step #1 Visualization and Matching - Equipment must fit the mine

Step #2 Develop Cycle Times - Need to know how much the equipment can produce to know how much equipment you need

Step #3 Identify Quantities of Equipment Needed

Main Steps Continued

Step #4 - Cross Check the Selection for practical fit

Step #5 - Estimate Economics Step #6 - Compare Different Fleets Step #7 - Make the Selection