2.5. Versatile Attachments and Applications

They have poor mobility. So, that is why it is preferable to place a truck very close to the excavator. So, very commonly you can see that the truck is placed at 90 degree. So, the truck is placed at 90 degree, this will be 90 to the bucket position. So, this is a common position. So, basically angle of swing is nothing but the horizontal angle between the digging and the dumping position between the loading and the dumping position.

The angle of swing refers to the horizontal angle formed when an excavator swings its bucket from the position where it digs to where it dumps. Ideally, the truck should be positioned at 90 degrees relative to the excavator to minimize the angle of swing. If the truck is further away, this angle increases, leading to longer cycle times and decreased productivity.

Imagine trying to toss a ball to a friend standing directly in front of you versus tossing it to a friend who is off to the side. The direct toss (90 degrees) is much easier and takes less time than throwing it at an angle (greater angle of swing), which takes more time and effort.

Ideal condition ideal production of shovel is based on 90 degrees swing that is what I told you, the truck will replace it 90 degree is ideal condition and the actual height of cut in your project site should be same as optimum height of cut, that combination that will give you ideal production.

For optimal productivity with an excavator (or shovel), two key conditions must be met: first, the angle of swing should be 90 degrees, and second, the actual height at which material is being cut should match the optimum height for the specific equipment. Meeting these conditions allows for the most efficient cycle of digging, swinging, and dumping.

Think of it like a basketball shot. To make a perfect shot, not only should you aim straight towards the hoop (90-degree swing) but you should also shoot from the right distance (optimum height). Missing either of these results in a longer shot time or a missed basket.

Now, let us see what are all the adjustment factors, we have to apply while doing the productivity estimation based upon the height of the cut of material actual height of cut of material in your project site and based upon the angle of swing that is going to depend upon the position of your truck relative to the position of your excavator.

Adjustment factors are crucial when estimating productivity. These adjustments take into account the actual height of cut compared to the optimum height, as well as the angle of swing. For example, if the actual height of cut is significantly lower or higher than the optimum height, productivity will likely decrease, necessitating a correction factor in your calculations.

Consider cooking a meal. If you're using a recipe that calls for 1 cup of water but you accidentally add 2 cups, the dish may not turn out well. Similarly, when conditions differ from the ideal in construction work, you must adjust your plan to ensure efficiency.

Another thing to be noted is truck spotting clearance. That means, as I told you, it is preferable to place a truck closer to the excavator. But at the same time, note that there should be some space left for the tail swing of the shovel.

Truck spotting clearance refers to the necessary space left between the truck and the excavator. Even though it is beneficial to position trucks closely to minimize swing angles, there must be adequate space to accommodate the swing of the excavator's tail to avoid collisions. This balance ensures safety and operational efficiency.

Imagine swinging a bat in a game. You need enough space around you to avoid hitting someone or something nearby. Similar to that, excavators need room to operate without risking damage to nearby vehicles or equipment.

Other important factor is haul unit exchange time. That means the time needed for the loaded truck to leave its position. And for a new truck that is an empty truck to take the position. That is called as a haul unit exchange time.

Haul unit exchange time is the duration taken for a loaded truck to leave the work site and for an empty truck to position itself for loading. Reducing this time is essential, as any delay impacts the total cycle time, ultimately affecting productivity. Efficient coordination between the trucks and the excavator can help minimize waiting times and increase overall output.

This is similar to a relay race where timely handovers between runners are crucial. If one runner takes too long to pass the baton, the team’s overall performance suffers.

Now let us see how to estimate the productivity of the shovel. So, for all these machines, the principle is going to be the same, you can see the formula everything is going to be similar only.

Estimating the productivity of a shovel involves a formula that considers the bucket's heaped volume, the fill factor, and the cycle time. It also accounts for adjustments based on the actual height of cut and swing angle, using specific correction factors to tailor estimates to actual conditions.

Think of it like measuring ingredients for baking a cake. You have to know the right volumes and adjust based on how full your measuring cup is and how long you take to mix the batter. Similarly, each factor in excavation impacts overall output.

As I told you earlier it is going to be 30 to 50% of maximum cutting height possible for this machine.

The optimum height of cut is crucial for effective excavation operations. It’s typically defined as 30 to 50% of the maximum digging height of the machine. The percentage applied often depends on the type of material being dug; for harder materials, a lower percentage is used, while for easier-to-dig materials, a higher percentage may be applied.

This concept can be likened to how you might work to lift a heavy object. If it’s very heavy, you might only try to lift the top half to avoid straining yourself. Adjusting how much you take on at once ensures you can manage the load effectively.

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