How to Measure Freight Elevator Throughput: A Cycle-Time Worksheet

Separate “can it carry this load?” from “how much does it move?”

Load suitability and workflow throughput answer different questions. The first concerns the complete load, handling equipment, dimensions, load distribution and approved operating method. The second concerns completed goods movements over time.

Begin only with a movement already approved for the equipment and site. If forklift entry, wheel loads, personnel carriage or clearances are unresolved, settle those issues with the responsible professionals before observing that proposed movement. JAFITA’s freight-elevator guidance and forklift loading checklist describe the information needed for those separate decisions.

JAFITA’s freight guidance identifies door operation, loading, unloading and queueing as relevant to throughput, and calls for recording loaded trips, operating hours and peak periods. The worksheet below turns those inputs into a record of an actual process.

Choose a route, a goods unit and an observation window

Write down exactly what you are measuring. “Warehouse elevator capacity” is too broad for an observation record. A useful description identifies the origin, destination, direction, handling method and period.

Choose a consistent goods unit: for example, the site’s approved pallet loads or a defined cart type. Do not silently treat a small carton, a partly loaded pallet and a full pallet as equivalent. Record the goods quantity separately from the total mass transported.

Keep different routes and conditions separate. A quiet-period measurement does not establish peak-period performance. Likewise, a single observed cycle can illustrate the method but cannot establish how reliably the process performs across a shift. Record the sample size and conditions alongside every result.

Start and finish the cycle in the same state

For this fixed-shuttle method, ready at origin means the car is back at the loading floor, the doorway is available under the normal operating procedure, and the car is ready to receive the next approved load.

The cycle ends when that state occurs again. If you stop timing at the destination, the return movement disappears from the repeated workload even though the next load still needs the car back at origin.

Record observable events without interfering with the operation. Use synchronized records where different observers cover the origin and destination, and follow the site’s arrangements for safe observation.

Calculate each interval from consecutive timestamps. Their sum must equal the elapsed time from cycle start to cycle finish. If an interruption occurs, identify the interval that contains it and add a note.

These intervals describe elapsed process time, not necessarily pure machine-motion time. For instance, the time between loading completion and door closure may include waiting before the door begins to move. If you need to distinguish that wait from the door’s movement, record an additional timestamp. Do not label the whole interval a door-speed problem without that evidence.

Use a complete-cycle calculation only where its assumptions fit

For a hypothetical shuttle with identical repeated cycles, a fixed outbound load and an initial ready-at-origin state:

Complete cycles = available window in seconds ÷ complete cycle time in seconds, rounded down.

Goods moved in those complete cycles = complete cycles × goods units per loaded outbound trip.

The same time basis must appear in both parts of the calculation. Do not divide minutes by seconds without converting them. Keep the observation window, starting state and per-trip goods quantity visible beside the result.

Worked example: an explicitly hypothetical shuttle

Assume that the site has already approved moving two pallet loads on each outbound trip. The following times are invented to demonstrate the arithmetic. They are not JAFITA specifications, measured customer results or recommended settings.

For an available window of 35 minutes:

• Convert the window: 35 × 60 = 2,100 seconds.
• Divide by the cycle: 2,100 ÷ 190 allows 11 complete cycles.
• Count the goods: 11 × 2 = 22 pallet loads in those complete cycles.
• Check the boundary: 11 × 190 = 2,090 seconds, leaving 10 seconds. Another complete cycle would require more time than remains.

Report the conclusion as 22 pallet loads in 11 complete hypothetical cycles within the stated 35-minute window. Do not turn that limited example into an hourly performance promise.

The rounding rule counts complete cycles. It is not a universal accounting rule for goods delivered during an unfinished final cycle. In an actual observation, count the goods that reach the destination and report any partially completed cycle separately.

Do not count a delay twice

A measured cycle may already contain waiting. If that same wait is deducted again from the available window, the calculation penalizes it twice.

Choose and describe the reporting method:

• Observed-window report: keep the actual window intact, count completed goods movements and record the interruptions that occurred within it. This is usually the clearest description of what happened during a variable operation.
• Fixed-cycle planning example: state the available window and the repeatable cycle assumption. Explain which interruptions are outside that model. It is an illustration of the stated conditions, not a replacement for observation.

Also include the return journey only once. A ready-to-ready measurement already contains it. Adding another return allowance to that measured interval creates a different error.

Avoid estimating the whole travel interval from shaft distance divided by rated speed. That shortcut does not describe the complete movement between the recorded events. Use observed timestamps for the operation you are studying.

Turn the longest intervals into questions, not automatic equipment changes

In the hypothetical example, the loading and unloading windows occupy more time than the outward and return travel intervals. That is a reason to examine the handling process. It does not prove that handling time can safely be reduced or that equipment speed is irrelevant to another project.

Build a bottleneck brief that separates what you observed from what you propose:

The next action might be better scheduling, further observation or an engineering review. The timing record alone does not authorize changing controls, reducing protections, exceeding the approved load or modifying an operating procedure.

Recognize when this worksheet is too simple

Use specialist traffic and process analysis where the problem includes multiple destinations, competing calls, several elevators, loaded return trips, changing load sizes or required waiting-time performance. Keep the observation records; they remain useful inputs even when the fixed-shuttle calculation is unsuitable.

Do not combine unlike routes into a single average and present the result as a peak guarantee. Preserve the conditions under which each result was obtained, including incomplete observations and unexplained interruptions.