5.1. Finding Balance Number of Bucket Loads

But the loading time will be number of bucket loads multiplied by the bucket cycle time.

To determine how long it will take to load a truck using buckets, you simply multiply the number of bucket loads by the time each bucket takes to fill. This is vital for planning and efficiency since it helps to estimate how many trucks can be filled over a set period.

Consider a kitchen where a chef needs to fill several bowls with flour using a measuring cup (bucket). If it takes 2 minutes to fill one cup and the chef needs to fill 5 cups, the total loading time will be 2 minutes × 5 = 10 minutes.

Another important thing you have to keep in mind is, for any machine whatever maybe the mission we have discussed about different types of machines so far. All the machines we are concerned about the safe gravimetric capacity of the machine. For every machine what is this safe operating load in terms of weight is given by the manufacturer, so that we call it as a gravimetric capacity.

Every machine comes with a specification called gravimetric capacity, which is the maximum weight that it can safely handle, as defined by the manufacturer. It is crucial to load machines within this capacity to prevent damage and ensure safe operation.

Imagine trying to lift a heavy box. If you know your strength can only safely lift 20 kg (the gravimetric capacity), attempting to lift 30 kg can lead to injury or a drop, just like overloading a machine can lead to malfunction.

So, we are not supposed to load the machine beyond the gravimetric capacity. So, since the density of material can vary from case to case, it is always advisable to check whether the load weight is within the safe gravimetric capacity.

Material density can significantly influence the actual weight loaded onto a machine. Therefore, checking the material's density and calculating the resulting load weight is critical to ensure it does not exceed the machine's safe operating limit.

If you were filling a truck with feathers versus rocks, the volume might be the same, but the rocks will weigh much more. This is similar to loading a machine: ensuring you know the weight of what you're loading is essential.

Check the load weight against the gravimetric capacity of the truck, how to check that? For that you need to know what is the unit weight of your material, if you know the density of your material you can multiply it by the volumetric load.

To check if the load is safe for the machine, you must first know the density of the material. By multiplying this density with the volume you are loading, you can calculate the total weight and compare it with the machine's gravimetric capacity.

Think about filling a suitcase. If you know that clothes weigh about 1 kg per liter and you have 10 liters of clothes, you can weigh your suitcase to ensure it is under the travel limit, just as you'd compare the load to the machine capacity.

If the material is going to be denser like wet sand or other denser material, what happens is there are more chances that your machine may be overloaded. That means the weight of material in the truck will be above the safe gravimetric capacity defined by the manufacturer.

When dealing with denser materials, the risk of overloading the machine increases. This can cause significant wear and tear on the machine, leading to costly repairs and possibly unsafe operating conditions.

Imagine driving a car with a heavy load beyond its weight limit. Just like the car suffers wear on its parts and becomes less efficient, overloading a machine leads to similar consequences.

So, you know that for most of the machines the tire cost almost to 35% of the truck operating cost. So, if you overload the machine it will result in abusing of tires and it will increase the tire cost significantly.

Overloading not only damages the machine but also significantly increases operating costs. For instance, the tires of a truck are a major component of its operating expenses, and overloading can lead to premature tire wear, thus increasing costs over time.

If you think of your car tires: if you constantly drive with too much weight in your trunk, the tires will wear out quicker. This results in more frequent replacements, just like overloading machines leads to higher costs.

So, balancing is very important, just now we discussed balancing the capacity of the interdependent machines very important. So, balancing the capacity of the hauling equipment and the excavator bucket size will result in maximum loading efficiency, and reduce total cost.

Finding the right balance between the number of trucks and the capacity of the excavator bucket is crucial. Ideally, the capacity of each truck should be 4 to 5 times that of the excavator's bucket to ensure both operate efficiently together.

When preparing a meal for many guests, you need to ensure you have enough pots and pans to cook all the food at once without leaving anything in the fridge. Similarly, balancing machines ensures that the material flow is optimal without bottlenecks.

So, that depends upon the cycle time of your truck and the cycle time of your excavator. So, divide the truck cycle time by the excavator cycle time, you will get the balance number of trucks.

To determine how many trucks are needed for one excavator, you divide the cycle time of the truck by the cycle time of the excavator. This calculation helps in achieving maximum productivity without unnecessary delays.

Think of a carpool system where cars drive to pick up passengers. If it takes 30 minutes for one driver to pick up and drop off passengers (the truck's cycle time) and only 20 minutes for the others, you can figure out how many cars are necessary to keep the process smooth.

So, these values are taken from the textbook by Peurifoy et al. So, they have given you the time needed for bottom dump truck and end dump truck, end dump is nothing but your rear dump.

Often the calculated balance number isn't a whole number, such as 7.4. You must decide whether to round down (to 7 trucks) or round up (to 8 trucks) based on economic analysis and productivity impacts. Ultimately, both options should be weighed to find the best outcome.

Imagine you are baking cookies and the recipe says 10.5 cookies are needed for a party. You must decide if you want to bake 10 or 11 cookies. If you bake too few, there won't be enough; but baking too many could leave you with less desirable extras.

When I round it to lower than the balanced number that means trucks are less than what is needed. So, trucks are more critical for the production, so here the loader will have the idle time, loader will be waiting for the truck.

If you round down too far, there might not be enough trucks ready to keep the loader busy. This means it might spend time waiting for trucks to return, which results in decreased productivity since the excavator can't work continuously.

If you're hosting a dinner party and only set the table with 5 plates instead of the needed 6, one guest will be left without a place at the table, causing delays in serving food.

In this case, number of trucks are greater than the balance number, so the trucks will have the idle time, truck will be waiting for the loader.

When you round up and have more trucks than necessary, it could lead to trucks waiting around for their turn to load. This situation can also reduce overall system productivity, as it does not efficiently utilize either the trucks or the loader.

At a school drop-off, if there are too many cars waiting in line (more than the teachers can take kids from), some cars will have to wait longer, causing frustration and inefficiency in the drop-off process.

That is why routine maintenance of the loader or the excavator is very important for the continuous running of the system.

Regular maintenance is critical for the loader or excavator to ensure they continue to function effectively. Breakdowns can disrupt operations significantly, while the impact of a broken truck may not be as severe. Thus, keeping the loader in optimal condition is crucial.

Just as a car requires regular oil changes and tune-ups to function smoothly, heavy machinery also requires consistent maintenance to prevent unexpected breakdowns and ensures reliable performance.

Now let us work on the problem on balancing the interdependent machines. So, here a loader is operating at 90-meter cube per hour and it has a 2.2 heap capacity bucket, and operates on 1.1-minute load cycle.

To solve practical problems in balancing machines, you need to know specific measurements such as the operation rate, bucket capacity, and loading time. These factors will be used in calculations to find out how many trucks are optimally needed for efficient operation.

When planning a road trip with friends, knowing how many snacks are needed (like understanding loading rates and capacities) is crucial. You need to gauge how many bags you can fit in the car versus how long it will take to pack each bag.

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