Load and Haul Fleet Selection Based on Fixed Plant Production

Load and Haul Fleet Selection Based on Fixed Plant Production

Ways to Estimate Productivity !!

The typical view is machine centred …

What are we going to do ? Review an approach which uses Crusher Output to drive fleet selection. Use a simple spreadsheet to manage this process e.g. no bunching or cycle mismatch included. Tie in the relevant concepts of earth and rock moving into this process. Seek to reinforces the outlook that You can’t Manage what you don’t Measure !

Key Questions Addressed What are the Production Targets and Rates for Fixed Plant? How much Time is Available? What Primary Load & Haul Production is required? How much of an Hour does the Loading Tool spend Loading? What is the Load Area Production Rate ? What are the Cycle Times for Haulers and Loading Tool? What is the Match of Loading Tool and Haulers ? What is the Key Characteristic of the Material? What does our Reality look like?

Bunching and Cycle Mismatch

Quarry Contacts Queensland and Northern Territory New South Wales Paul Soden Hastings Deering, Brisbane New South Wales Andrew Black WesTrac, Sydney Victoria Ian Collins William Adams, Melbourne Tasmania Stuart Mc Donald William Adams, Launceston South Australia Mark Taylor Cavpower Adelaide Western Australia Steve Sakich WesTrac Perth

Any Questions ? The End

Concepts Time Available Material Density Fleet Match Work Days per year Work Hours per Day Job Efficiency – Work Minutes per Work Hour Load Area Activities Material Density Load Factor and Fragmentation Fleet Match Cycle Times Bucket to Body Sizing – Effective Pass Ratios Bucket Fill Factor

Concepts Time Available Material Density Fleet Match Work Days per year Work Hours per Day Job Efficiency – Work Minutes per Work Hour Load Area Activities Material Density Load Factor and Fragmentation Fleet Match Cycle Times Bucket to Body Sizing – Effective Pass Ratios Bucket Fill Factor

Work Hours Available per Year Availability & Utilization An Example Job Efficiency Factors Mismatch Bunching Operator Efficiency (85% Job Efficiency) Utilization Loss Ready, but unmanned Shift Change Lunch & Meetings Scheduled Downtime &PM's (87.5% Utilization) Off Time Loss Holidays Weather (4.1% Off Time) Machine Availability Loss Unscheduled Downtime (90% On-Shift Availability) PRODUCTIVE TIME 6615 HRS 735 HRS 1050 360 Machine Operating Hours (6615 HRS) Machine Scheduled Hours (7350 HRS) Mine Scheduled Hours (8400 HRS) Total Annual Hours (8760 HRS) 10 % of 7350 4.1 % 8760 12.5% 8400

Work Days per Year Full Days 220 days Partial Days 48 days Partial Day Factor 0.50

Load & Haul Work Hours per Day

Load & Haul Work Hours per Day Load and Haul Scheduled Hours / Day 10 hours less Non Operational Time Mobilisation Toolbox Talk - Inspect - Transit 20 minutes Transit - Refuel - Shut Down 20 minutes Breaks including Transit time AM / PM Breaks 20 minutes Lunch 45 minutes Subtotal of Non Operational Time 1.75 hours less Non Primary Load and Haul Stock movement 0.75 hours Overburden 0 hours Subtotal Non-Primary Load and Haul 0.75 hours Work Hours per Day 7.5 hours

Job Efficiency / Work Minutes per Work Hour Job Efficiency is one of the most complex elements of estimating production since it is influenced by factors such as operator skill, minor repairs and adjustments, personal delays and delays caused by job layout. An approximation of efficiency, if no job data is available, is given below. Efficiency Operation Working Hour Factor Day 50 minute hour 0.83 Night 45 minute hour 0.75 These factors do not account for delays due to weather or machine downtime for maintenance and repairs.You must account for such factors based on experience and local conditions. What about time lost for watering the load area ?

Analysis of Face Loader Activity

Concepts Time Available Material Density Fleet Match Work Days per year Work Hours per Day Job Efficiency – Work Minutes per Work Hour Load Area Activities Material Density Load Factor and Fragmentation Fleet Match Cycle Times Bucket to Body Sizing – Effective Pass Ratios Bucket Fill Factor

Density of Materials Material Bank Loose Load kg/m 3 kg/m 3 Factor Gravel - pit run 2179 1930 .89 Earth-dry 1900 1510 .80 Earth- wet 2020 1600 .79 Clay – natural bed 2020 1660 .82 Topsoil 1370 950 .70 Shale 1660 1250 .75 Granite -broken 2730 1660 .61 Limestone 2610 1540 .59 Full Table in PHB 42 P27-4

Concepts Time Available Material Density Fleet Match Work Days per year Work Hours per Day Job Efficiency – Work Minutes per Work Hour Load Area Activities Material Density Load Factor and Fragmentation Fleet Match Cycle Times Bucket to Body Sizing – Effective Pass Ratios Bucket Fill Factor

Machine Production CYCLE TIME Operator Skill LOAD Fixed Time RETURN Variable Time Delays HAUL Variable Time DUMP Fixed Time

Loading Tool / Hauler Pass Match Target Truck Load Time 2 minutes Target Exchange Time 0.7 minutes Target Pass Match Loader / Hauler = 3-5 Excavator / Hauler = 4-6

Concepts Time Available Material Density Fleet Match Work Days per year Work Hours per Day Job Efficiency – Work Minutes per Work Hour Load Area Activities Material Density Load Factor and Fragmentation Fleet Match Cycle Times Bucket to Body Sizing – Effective Pass Ratios Bucket Fill Factor

Bucket Fill Factor (BFF) BFF as % of Heaped Capacity Material Moist Loam Sand and Gravel Mix Rock - Well Blasted Rock - Poorly Blasted 12 –20mm Aggregate BFF as % of Heaped Capacity A - 100-120 % B - 95-110 % C - 80 - 95 % 50 - 75 % 85 - 90 This overhead gives a rough idea of the kinds of fill factors you can expect in various types of materials. This can also be found in the Performance Handbook. When doing calculations, we typically use the midpoint of the range. A B C BFF for Wheel Loader buckets tend to be 5 – 10 % higher than Excavator buckets due to different angles of repose for SAE rating. PHB 42 Pages 4-156, 9-161

Quarry Contacts Queensland and Northern Territory New South Wales Paul Soden Hastings Deering, Brisbane New South Wales Andrew Black WesTrac, Sydney Victoria Ian Collins William Adams, Melbourne Tasmania Stuart Mc Donald William Adams, Launceston South Australia Mark Taylor Cavpower Adelaide Western Australia Steve Sakich WesTrac Perth

Any Questions ? The End