2.3. Job Efficiency and Operating Time

So, this cutting and pushing will go together. So, the time required to push, backtrack and maneuver into position, so that is called as a cycle time of the bulldozer. So, you are going to cut the earth, push the earth, dump it at the required place, then backtrack, backtrack in the sense you are going to return, return back to the original position where you want to do the dosing operation again.

The cycle time of a bulldozer is the total time it takes to complete one operational loop, which includes cutting, pushing, and returning. This time is crucial for calculating how efficiently the bulldozer can work. In essence, every time the machine cuts the earth, pushes it to a dump site, and then returns to start over again, it completes a cycle. Understanding cycle time helps in planning and optimizing operations.

Imagine a chef making a pizza. First, they prepare the dough (cutting), then spread the sauce and toppings (pushing), and finally, they put it in the oven (dumping). Once baked, they retrieve the pizza from the oven and clean the area for the next pizza (backtracking). The entire process is similar to the bulldozer's cycle time.

So, other things are maneuvering, maneuvering in the sense whatever adjustments you do, like for increasing the speed, accelerating or decreasing the speed, changing the gear, so the time needed for changing the gear, all those things comes under the maneuvering. So, we call this as fixed time, this is fixed time and this one is variable time, your push and backtrack it is called this variable time, why do we call this push time and backtrack time as variable time?

Maneuver time is considered fixed because it involves the time taken for specific adjustments like changing speeds or gears. In contrast, push time and backtrack time are variable; they depend on the distance being traveled. For example, if the distance to the dump site increases, the push time increases, making it a variable factor in the overall cycle time.

Think of driving a car. The time it takes to change gears (maneuvering) is relatively consistent regardless of how far you drive. However, if you drive to a location that's far away versus one that's close, the driving time varies depending on the distance, which parallels the variable push and backtrack times.

Because it is variable depending upon your haul distance. So, greater your haul distance greater will be a push time and return time or backtrack time. So, this is solely dependent upon your haul distance, so this is dependent upon your haul distance, so that is why we call it as variable obviously it depends upon the speed also.

The formula for calculating the time needed to push or backtrack a bulldozer is directly linked to the haul distance and the speed of the machine. Essentially, a longer distance means we'll spend more time pushing the load and coming back. The machine's operational speed also influences how long these tasks will take, meaning both haul distance and speed are crucial to accurately determining time.

Imagine walking a dog. If you have a small yard, it takes just a few minutes to walk around, but if you take your dog to a large park, you'll spend significantly more time walking back and forth. Similarly, longer haul distances mean more time for bulldozer operations.

So, now let us see what is this maneuver time? So, already I told you maneuver time is nothing, but the time needed for changing your speed accelerating, changing the gears, or reducing the speed, so that is what is called as a maneuver time. So, this maneuver time will depend upon the type of transmission.

Maneuver time involves the adjustments made by the operator for speed and gear changes. This time can vary based on the type of transmission the bulldozer uses—manual or automatic. Manual gear changes might take longer as the operator must physically shift gears, while automatic systems handle these changes more efficiently, resulting in shorter maneuver times.

Consider a bike with manual gears versus an automatic bike. Changing gears in a manual bike requires more attention and takes longer compared to an automatic bike where the gears shift seamlessly. This makes the bike with an automatic transmission quicker in response, much like bulldozers operated with automatic transmissions.

So, now let us see how to estimate the productivity of the bulldozer. So, we are going to estimate the productivity a lose meter cube per hour. As I told you whenever you express the volume, you should be very specific that whether you are expressing the volume in the loosen state or bank state, that is natural state or in the compacted state.

Estimating bulldozer productivity involves calculating how much material can be moved in a specified timeframe, typically loose cubic meters per hour. It's crucial to specify whether you refer to loose material (after excavation) or bank material (before excavation) since each has different implications for productivity calculations.

When filling a bag with flour, the amount it holds depends on how packed it is. A loosely filled bag has less weight than a tightly packed one. Similarly, distinguishing between loose and bank state in earthmoving operations affects productivity estimates.

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