1.4. Effect of Trucks on Productivity

Now let us find the balance number of trucks needed for one loader. So, that depends upon your the balance number of trucks per loader going to serve by one loader is equal to your truck cycle time divided by load of cycle time. So, you have estimated the truck cycle time earlier, so estimated it is 39.5. (Refer Slide Time: 39:23) The truck cycle time is 39.5 and the loader cycle time is 5.5, we have calculated the loader cycle time as 5.5. So, this gives me the balance number of 7.18.

To determine the efficient number of trucks needed to keep a loader operating optimally, we calculate the balance number of trucks. This is done using the formula: Balance Number of Trucks = Truck Cycle Time / Loader Cycle Time. In this case, the truck cycle time is 39.5 minutes, while the loader cycle time is 5.5 minutes. When we divide these values, we find the balance number of trucks to be approximately 7.18. This means that ideally, around 7 to 8 trucks should be used to support one loader effectively.

Imagine a restaurant kitchen where one chef (the loader) can only prepare a certain number of meals (the cycle time). If too many waitstaff (the trucks) are available to pick up the meals, they end up standing around waiting for the chef to prepare food, which is inefficient. Just as the right balance of trucks is crucial for productivity, having the right number of waitstaff relative to the number of chefs ensures that food is served efficiently, minimizing waiting time.

So, just to give you a better explanation I am just working out what will be the economics when I go for different number of trucks. Say if I go for 5 number of trucks, 6, 7, 8 and 9, how the productivity will vary, how the unit production cost will vary? We will work it out and see, so that will get a clear picture on what is the effect of number of trucks, and what is the effect of increasing the number of trucks beyond the balance number on the unit production cost.

To truly understand the impact of the number of trucks on productivity, it’s essential to evaluate different scenarios. If we analyze how productivity changes with 5, 6, 7, 8, and 9 trucks, we can see different results. As the number of trucks increases to 7 (the balance point), productivity will rise. However, if we add more trucks beyond this point, while it might seem like productivity would continue to increase, in reality, there is a limit dictated by the loader's capacity. This effect can also lead to increased costs, as more trucks generally mean higher operational expenses without corresponding gains in productivity.

Think of a highway toll booth. If there are five lanes (trucks) and traffic is flowing nicely, efficiency is high. If we add lanes, keeping the same number of toll booths (loaders), the added lanes start to make cars wait because they can’t be processed any faster. This is akin to adding more trucks than needed; there’s no increase in productivity, just more waiting and potentially higher toll costs!

So, basically how to estimate the job production? So, it is nothing but your single truck productivity multiplied by number of trucks, that will give you the job production. So, provided the number of trucks are lesser than the balance number. In that case you can calculate by that, because when the trucks are lesser than the balance number or equal to balance number your truck cycle time will govern the productivity.

The job production can be calculated by multiplying the productivity of a single truck by the total number of trucks, as long as this number does not exceed the balance number. For example, if one truck can handle a certain volume efficiently when there are fewer trucks, then multiplying this volume by the number of trucks gives the job production capacity. However, if the number of trucks meets or exceeds the balance number, the loader’s limitations will start to restrict output despite having more trucks.

Imagine a school with one teacher (the loader) and a set number of students (the trucks). If there are too few students, the teacher can give a lot of attention and the class is productive. If there are too many students beyond what the teacher can handle effectively, additional students won’t improve overall learning—they’ll just add to the chaos. This is similar to how productivity peaks with the right number of trucks.

But beyond the balance number, so you can see that number of trucks are more so the truck will be waiting for the loader unless the loader is available your truck cannot do the job. So, the productivity here will be controlled by your loader.

When the number of trucks exceeds the balance number, productivity is negatively impacted; the additional trucks become idle, waiting for the loader to be available. Thus, regardless of how many trucks are present, productivity cannot increase beyond what the loader can process, leading to inefficiencies and increased costs, since those trucks still need operation.

Consider a bakery where there is one oven (the loader) and several bakers (the trucks). If there are too many bakers but only one oven, the bakers have to wait for their turn to put their items in the oven, which leads to wasted time and resources even though you have more bakers, similar to having too many trucks waiting for the loader.

Now let us work out the economics because most of the decisions are based upon the economics. People are more concerned about the unit production cost associated with the machine.

Analyzing the economics of truck-loader combinations involves calculating the unit production cost—essentially how much it costs to produce one unit of output. This involves considering both the operational costs of the trucks and the loader. Different combinations can be evaluated to determine the most cost-efficient scenario based on productivity and expenses.

Think about budgeting for a party. If you have too few people cooking (the trucks) compared to how much food needs to be prepared (the loader), the cost to feed everyone per person could rise. By analyzing the costs of hiring more cooks but understanding they won't necessarily prepare more food, you can make smarter choices about your party planning.

If I go for 7 my unit production cost is 162.47. If I go for 8 trucks my unit production cost is 176.67, so it is preferable to round it to the lower number.

When evaluating unit production costs, it is important to analyze costs associated with different numbers of trucks. If using 7 trucks yields a lower cost compared to 8, it’s more economically advantageous to choose the lower number. This decision also builds in some flexibility or downtime for the loader, allowing it to work more efficiently without unnecessary constraints caused by an excess number of trucks.

Imagine allocating hours for studying before an exam. If you plan for 8 hours but find you can learn everything you need in 7, studying for an extra hour might just lead to burnout without any added benefit. Similarly, opting for fewer trucks limits costs while maintaining efficiency, just like effective study time management.

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