4.3 - Economics of Rounding Truck Numbers
Enroll to start learning
You’ve not yet enrolled in this course. Please enroll for free to listen to audio lessons, classroom podcasts and take practice test.
Interactive Audio Lesson
Listen to a student-teacher conversation explaining the topic in a relatable way.
Understanding Truck Loading Capacity
🔒 Unlock Audio Lesson
Sign up and enroll to listen to this audio lesson
Today, we'll discuss the crucial concept of gravimetric capacity in truck loading. Why do you think it's important not to exceed this limit?
Isn't it because it can damage the truck?
Exactly! Overloading can lead to severe wear and tear, especially on tires, which can account for up to 35% of operating costs. Remember the acronym 'S.A.F.E' - Safety, Efficiency, and Financial impact, to help us remember why we must adhere to these limits.
What happens if we overload it anyway?
Good question! Overloading can lead to premature aging of trucks and increased ownership costs. Can anyone summarize the main costs affected by overloading?
The wear on tires and potential need for truck replacement!
Well done! Keeping our trucks within the safe limit not only helps maintain safety but also ensures financial stability.
Calculating Loading and Hauling Times
🔒 Unlock Audio Lesson
Sign up and enroll to listen to this audio lesson
Next, let's look at how we can calculate loading and hauling times. Who can explain how the loading time is determined?
Is it based on the number of bucket loads multiplied by the cycle time?
Great answer! And what about the factors affecting hauling time?
It depends on the haul distance and speed, right?
Yes! Remember the acronym 'S.T.E.P' - Speed, Time, Efficiency, and Payload. Understanding these factors can help us optimize our operations. Now, can you calculate the haul time if we know the distance to be 50 meters and speed to be 2 meters per minute?
It would take 25 minutes to haul!
Correct! Nice work. It's critical to keep these calculations in mind when planning construction logistics.
Balancing Truck and Excavator Productivity
🔒 Unlock Audio Lesson
Sign up and enroll to listen to this audio lesson
Now, we need to discuss the balance between trucks and excavators. Why is it important to match their capacities?
To minimize waiting time and improve productivity!
Exactly! If trucks exceed the balance number, the loader may be overwhelmed, leading to idle trucks. If fewer, the loader may wait for trucks. This is where understanding the concept of 'balance number' comes in. How do we derive this?
By dividing truck cycle time by excavator cycle time?
Right! Always apply logical reasoning. If the balance number is 7.4 but we round it down to 7, what might be the impact on productivity?
There could be idle time for the loader, right?
Exactly! Balancing these numbers is key to maximizing efficiency in construction operations.
Economic Considerations in Truck Rounding
🔒 Unlock Audio Lesson
Sign up and enroll to listen to this audio lesson
Finally, let’s consider the economic implications of our choices. What factors should we analyze when deciding how many trucks to use?
We should consider the cost of operations and productivity.
Correct! In deciding to round up or down, always compare production cost for both scenarios. What's a good practice to follow?
Evaluate both options before finalizing the number of trucks!
Exactly! And remember, the goal is to achieve maximum efficiency while minimizing costs.
Introduction & Overview
Read summaries of the section's main ideas at different levels of detail.
Quick Overview
Standard
In this section, we discuss the significance of adhering to the gravimetric capacity of trucks to ensure safe and efficient operation. It covers important considerations for loading times, dump times, and how to calculate the ideal number of trucks based on excavator cycle times. Additionally, we highlight the economic impact of overloading trucks and the importance of balancing the productivity of excavators and trucks.
Detailed
Detailed Summary
In this section, we delve into the economics of truck loading in construction machinery, emphasizing the need to adhere to manufacturer-defined gravimetric capacities. The loading time is calculated based on the number of bucket loads and bucket cycle time. We also elaborate on how to derive the actual load weight by multiplying material density with volume, ensuring it fits within the safe operating load.
Overloading can lead to premature wear on machinery, particularly tires, significantly affecting overall operational costs. The section discusses the importance of both dumping and hauling times, influenced by various factors like material type and site congestion, ultimately affecting production efficiency. We analyze how to balance the number of trucks with the excavator's loading capacity to optimize productivity. Notably, rounding numbers to determine the number of trucks presents different operational outcomes, emphasizing the need for an economical decision-making approach based on productivity calculations.
Audio Book
Dive deep into the subject with an immersive audiobook experience.
Importance of Gravimetric Capacity
Chapter 1 of 6
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
But the loading time will be number of bucket loads multiplied by the bucket cycle time. Another important thing you have to keep in mind is, for any machine whatever may be 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 gravimetric capacity.
Detailed Explanation
Gravimetric capacity refers to the maximum weight a machine can safely handle, as specified by the manufacturer. It is vital to adhere to this capacity to prevent damage to the machine. The loading time directly affects the productivity of the truck and is determined by the number of bucket loads and the time it takes to fill those buckets.
Examples & Analogies
Imagine trying to lift a weight that exceeds your strength. Just as you could injure yourself trying to lift too much, a truck can get damaged if overloaded, leading to costly repairs. Following the manufacturer's guidelines ensures the machine operates efficiently and lasts longer.
Calculating Safe Loading Capacity
Chapter 2 of 6
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
So, only that capacity your machine can take because the structural frame of the machine is designed to handle that particular load only. 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.
Detailed Explanation
Each machine has a defined gravimetric capacity based on its design. To ensure safety and efficiency, the total weight of the material being loaded must not exceed this capacity. The density of materials differs, which can affect the actual weight loaded onto the truck. Always calculate the material’s weight using its density and volume before loading to avoid overloading.
Examples & Analogies
Think of packing a suitcase: if you pack it too full, it becomes difficult to carry, just as an overloaded truck can become unwieldy and cause more wear. By checking the weight before loading, you ensure everything fits perfectly and operates smoothly.
Handling Different Material Densities
Chapter 3 of 6
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
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 you will get the actual weight of material in the truck, you will get the truck load.
Detailed Explanation
To verify that the truck's load is within the safe limit, calculate the total weight by multiplying the density of the material by its volume. This calculation helps ensure you do not exceed the truck's gravimetric capacity, thus avoiding potential mechanical issues. Understanding the density of your materials is crucial in this calculation.
Examples & Analogies
Imagine you're filling a jar with candies of different sizes. Depending on the type of candy, the jar can hold different amounts even if it looks the same. Similarly, the weight of materials can vary even with the same volume, which makes measuring the weight essential before truck loading.
Consequences of Overloading
Chapter 4 of 6
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
If the material is going to be denser like wet sand or other denser materials, what happens is there are more chances that your machine may be overloaded...overloading will result in abusive wear and can lead to increased operating costs, especially for tires, which constitute a significant portion of the truck's operating costs.
Detailed Explanation
Loading denser materials can lead to overloading, which increases wear and tear on the machine, particularly the tires. Excessive weight can cause more rapid aging of truck components, leading to higher operational costs and potential breakdowns that require costly repairs or replacements.
Examples & Analogies
Consider driving a car with too many passengers; just like that can make the car struggle and wear out faster, overloading a truck stresses its structure and increases maintenance costs, ultimately leading to more frequent replacements.
Balancing Truck and Excavator Capacity
Chapter 5 of 6
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
So, it is preferable to go for the choice of bottom dump, so that you can have reduced cycle time and increase productivity. Balancing the capacity of the hauling equipment and the excavator bucket size will result in maximum loading efficiency, and reduce total cost.
Detailed Explanation
To maximize efficiency in construction operations, it is essential to balance the capacities of hauling trucks with the excavator bucket sizes. An optimal ratio allows for smooth workflow with minimal waiting time, ultimately leading to reduced costs and increased productivity.
Examples & Analogies
Imagine a relay race where the runners (trucks) have to match the speed and distance of the baton (excavator). If one is faster and the other is slow, they disrupt each other's performance. Ensuring they work together harmoniously increases efficiency significantly.
Rounding Truck Numbers: Economics of Decision Making
Chapter 6 of 6
🔒 Unlock Audio Chapter
Sign up and enroll to access the full audio experience
Chapter Content
So, when they are compatible, you can see that the cycle time will be less. But more often you can see that you may not get a whole number. For example, If I am getting the balance number say 7.4, whether I should round it to 7 or I should round it to 8 trucks, we have to decide, how to decide that?
Detailed Explanation
When determining how many trucks to use based on calculated balancing numbers, consider both operational efficiency and costs. If rounding down results in too few trucks, productivity may suffer due to delays. Conversely, rounding up could lead to excess capacity and idle time. Assessing the economics of both approaches ensures a logical and informed decision.
Examples & Analogies
Think about filling up a car’s gas tank. If you don't fill it enough, you might run out of gas too soon; if you overfill it, you waste money. Rounding to the right number of trucks is like ensuring your gas tank is optimally full without overspending or running out of fuel.
Key Concepts
-
Gravimetric Capacity: The safe operating weight limit set by the manufacturer.
-
Loading Time: Determined by bucket loads and cycle time.
-
Haul Time: Influenced by distance and speed of the truck.
-
Balance Number: Essential for optimizing the number of trucks relative to excavators.
Examples & Applications
If a truck's gravimetric capacity is 20,000 pounds and the material density is 0.8 pounds per cubic foot, the maximum volume of material that can be safely loaded is 25,000 cubic feet.
A loader takes 1.5 minutes to load a bucket, so to fill a truck with a payload of 10 cubic meters, it would take 6 buckets, resulting in a total loading time of 9 minutes.
Memory Aids
Interactive tools to help you remember key concepts
Rhymes
Load it light, ride it bright; keep the weight to avoid the fright!
Stories
Imagine a team of trucks working tirelessly, each one needing to stay under capacity to keep rolling smoothly without breakage.
Memory Tools
Remember S.A.F.E: Safety, Avoid costs, Function & Efficiency.
Acronyms
H.E.L.P
Hauling Efficiency
Loading Precision.
Flash Cards
Glossary
- Gravimetric Capacity
The maximum safe operating load defined by the manufacturer for a machine in terms of weight.
- Bucket Cycle Time
The time taken for a bucket to make a complete loading cycle.
- Loading Time
The total time required to load the material into the truck.
- Haul Time
The duration required to transport material from one point to another.
- Balance Number
The optimal number of trucks that can be effectively utilized in coordination with an excavator.
Reference links
Supplementary resources to enhance your learning experience.