Calculators · Machinery
Excavator and loader productivity calculator
Earthmoving output comes down to three things: how much each bucket carries, how many cycles the machine completes in an hour, and how much of each hour is spent working. These calculators estimate hourly production of an excavator or wheel loader, the number of passes to fill a truck, and how many trucks keep the loading machine busy. They are planning estimates; site conditions, operator skill and material vary widely.
Hourly production
Multiplies bucket capacity by the fill factor and the number of cycles per hour, reduced by job efficiency — the share of each hour actually spent digging. A 50-minute working hour is the usual planning assumption.
cycles/h = 3,600 / cycle time × working minutes / 60 production = bucket × fill × cycles/h
Passes to fill a truck
Works out how many bucket loads fill a truck to its payload and how long loading takes. Three to five passes is a well-matched loader and truck; more than about six slows the whole operation.
per pass = bucket × fill × density passes = ⌈payload / per pass⌉
Trucks needed to keep the loader busy
A loader works continuously only if a truck is always waiting. The number of trucks needed is the full truck cycle — loading plus haul, dump and return — divided by the loading time.
trucks = (loading time + travel time) / loading time
Worked example: a 20-tonne excavator loading trucks
- A 1.2 m³ bucket at 90% fill on a 20 s cycle, working 50 minutes an hour, completes 150 cycles.
- Production: 1.2 × 0.9 × 150 = 162 m³ of loose material, about 259 t at 1.6 t/m³.
- Each pass carries 1.94 t of 1.8 t/m³ gravel, so a 25 t truck needs 13 passes — about 4.3 minutes.
- With an 18-minute haul, dump and return, six trucks keep the excavator loading continuously.
Typical bucket fill factors
| Material | Fill factor |
|---|---|
| Moist loam, sandy clay | about 100 – 110% |
| Sand and gravel | about 95 – 110% |
| Hard, tough clay | about 80 – 90% |
| Well-blasted rock | about 60 – 75% |
| Poorly blasted rock | about 40 – 50% |
Related
About these results
Results are theoretical estimates from standard engineering formulas. Real-world figures depend on conditions these formulas do not capture. Always follow the manufacturer's specifications for maintenance, loading and safety decisions.
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