Turn loader cycles into reliable quarry output numbers. Compare shifts, downtime, and material conditions easily. Plan trucks, stockpiles, and budgets with confidence now always.
Enter your equipment and operating assumptions. Use optional trucking fields to estimate fleet needs.
Sample values illustrate how production changes with cycle time and efficiency. Replace with your field assumptions.
| Scenario | Bucket (m³) | Fill (%) | Cycle (s) | Density (t/m³) | Net efficiency (%) | Net t/hr | Net BCM/hr |
|---|---|---|---|---|---|---|---|
| Baseline | 2.50 | 95 | 35 | 1.75 | 62.0 | 265.1 | 121.2 |
| Faster cycles | 2.50 | 95 | 30 | 1.75 | 62.0 | 309.2 | 141.4 |
| Higher efficiency | 2.50 | 95 | 35 | 1.75 | 72.0 | 307.8 | 140.7 |
Tip: If your density is in kg/m³, divide by 1000 to convert to t/m³.
Production starts with cycles per hour: 3600 divided by measured cycle seconds. Many quarry loading patterns run 25–45 second cycles when truck spotting is clean and the face is tight. Longer travel, poor lighting, or uneven benches can push cycles above 60 seconds. Because cycle time is a divisor, small improvements often yield large gains. Time 10–20 consecutive cycles under normal traffic, then repeat after breaks. Avoid single “best run” measurements that cannot be sustained across multiple shifts.
Bucket capacity is the geometric size, but fill factor reflects how consistently material packs and heaps. Typical values range from 85% for sticky or segregated material to 105% for free‑flowing rock with skilled operators. Validate fill factor using payload averages or scale tickets. If fragmentation, bucket type, or digging method changes, revise fill factor before adjusting efficiency.
Net efficiency multiplies availability, utilization, site efficiency, delay allowance, and loss allowance. Many operations plan between 55% and 75% net once fueling, inspections, meetings, and rehandle are counted. Use “minutes lost per hour” to capture site constraints such as traffic control, crusher stops, or water truck interference. Put dispatch waiting into utilization, not cycle time.
Converting loose m³ to tonnes requires a loose bulk density, often 1.6–2.0 t/m³ for many crushed rock products, but moisture and gradation can shift it. Swell factor converts loose volume back to bank volume (BCM) for in‑situ tracking; common ranges are 1.15–1.35 depending on blast quality. Keep density and swell matched to the same material state.
The optional trucking check estimates whether hauling can keep pace with the loader’s net t/hr. If trucks are short, the loader waits and utilization drops even if mechanical availability is high. Improve balance by reducing haul cycle time, raising payload, or staging a buffer stockpile. Compare calculated rates to crusher or plant capacity to identify the true bottleneck.
Loose m³ is measured after excavation when material expands. Bank m³ represents in‑place volume before digging. The calculator converts loose to bank using swell factor so schedules and pay quantities match reporting.
Time a sequence of cycles from bucket entry to the next bucket entry under normal conditions. Capture at least 10–20 cycles, exclude abnormal interruptions, and use the average. Repeat when spotting or face layout changes.
Use scale ticket data with known truck volume, a stockpile survey with tonnage records, or lab bulk density tests. Choose loose density if material is weighed after loading, and update it when moisture varies.
For many quarry operations, 55%–75% net is realistic once meetings, fueling, queueing, and routine delays are included. If you are unsure, start near 65% and refine using shift production logs.
It calculates per‑truck capacity from payload, trips per hour (60 ÷ cycle minutes), and a utilization factor, then compares that rate to the loader’s net t/hr. The result is an approximate truck count.
Production drops when fragmentation is poor, trucks queue, faces are congested, or downtime is underestimated. Recheck cycle time sampling, confirm fill factor against scale averages, and record delays so efficiency reflects real constraints.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.