How to Report Time Usage Model (TUM) Trucks in APS Using Chrono Report – Alastri Quick Articles

“Instantaneous Trucks” vs “TUM Trucks”

Firstly, it’s important to understand the difference between an “instantaneous truck” and a “TUM truck”. An “instantaneous truck” is operating and productive at an instant in time. A “TUM truck” is the number of truck hours in a period divided by the number of hours per truck in the period, based on the TUM.

In reality, trucks do not respect the TUM in an instant in time - in any one instant, the truck is either available or unavailable, not a mixture of the two. There’s a probability of whether a truck will be operating instantly in the future (the TUM is the average over an extended period). This is the most correct way to think about trucks on an instantaneous basis and for very short term scheduling. The TUM accounts for but does not explicitly contain the frequency and duration of downtime events (a cyclone vs a broken bucket tooth).

The Instant Units is a calculated field equal to the number of units entered, multiplied by the PA, UPA, OE, UA, and PF. Conceptually, the Instant Units is the exact number of trucks expected to be available for use at any instant over the schedule.

Figure 1. Instantaneous Truck Calculation

TUM Trucks

Reporting TUM trucks involves looking at consumed truck hours over the period. Truck hours are based on the cycle time of the truck (when being loaded by the specific digger), the truck’s payload, the quantity and type of material moved, and the time usage model (TUM) which applies to the truck.

Cycle Time

Haul Infinity, integrated into APS, determines the cycle time. Therefore, in order for useful cycle times to come through, the haul network must be updated and accurately reflect the roads being used.

The truck’s cycle time consists of:

Spot Time at Loader
Loading Time
Loaded Travel Time
Spot at Dump
Dumping Time
Unloaded Travel Time
TKPH Delay (if TKPH constrains the truck cycle time)
Queue Time

The cycle time of a truck calculated by Haul Infinity depends on the truck, loader, source, destination, and operating condition. The payload of the truck is entered into Haul Infinity but can be overridden by the operating condition.

Chrono Report

TUM trucks can be reported in a Chrono Report by dividing the number of hours available per truck by the productive hours of that particular truck. The number of hours available per truck is available in the Calendar Data Source field list. Users can also find the total productive hours of a particular truck model Mining Data Source field list. A filter must be applied to return the productive hours of the required truck model. These fields and the calculation of truck hours is shown in the image below.