Professional Courses
Industry-relevant training in Business, Technology, and Design to help professionals and graduates upskill for real-world careers.
Categories
Interactive Games
Fun, engaging games to boost memory, math fluency, typing speed, and English skills—perfect for learners of all ages.
Typing
Memory
Math
English Adventures
Knowledge
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.
Introduction to Productivity and Key Factors
Unlock Audio Lesson
Today, we're going to talk about estimating productivity in excavation operations. Can anyone tell me why it might be important to understand productivity?
It's important to know how much work can be done in a certain time to plan better!
Exactly! One key factor is the angle of swing. Does anyone know what this term means?
I think it refers to the horizontal angle between where the bucket digs and where it dumps.
Correct! The ideal angle of swing is 90 degrees. Let's remember it as 'Optimal 90'—a mnemonic to keep in mind. What happens as the angle increases?
The cycle time increases, which reduces productivity?
Right! As the cycle time increases, productivity decreases. But how does height of cut play into this?
If the height of cut is lower than optimum, we need to apply a correction factor!
That's correct! Now, let’s summarize: keeping the angle of swing at 90 degrees and the height of cut optimal are crucial for high productivity.
Adjustment Factors for Productivity
Unlock Audio Lesson
Now, let’s dive deeper into adjustment factors. Student_1, can you remind us how to calculate when the actual height of cut is less than the optimum?
Sure! We calculate it by dividing the actual height by the optimum height to find the percentage.
Correct! If the percentage is 100%, no correction factor is needed. What happens if it’s less?
Then it means productivity will be reduced, and we need to apply the correction factor.
True! And what about when the angle of swing is above or below 90 degrees?
If above 90 degrees, the correction factor decreases, reducing productivity, and if below, it increases productivity.
Nice summary! Remembering 'High Swing, Low Productivity' can help recall this relationship.
That's a good tip!
Truck Spotting and Haul Unit Exchange
Unlock Audio Lesson
Let’s shift gears and talk about truck spotting clearance. Why is it important?
It ensures the backhoe or excavator can swing without hitting the truck, right?
Exactly! We must also consider haul unit exchange time. Student_3, can you explain this concept?
Yes! It's the time it takes for a loaded truck to leave and for an empty truck to arrive for loading.
Good! Why is this time critical to managing productivity?
If trucks aren't available, the excavator has to wait, increasing cycle time and reducing productivity!
Precisely! Effective truck management helps minimize this waiting time and maximizes efficiency.
Calculating Productivity
Unlock Audio Lesson
Let's put our knowledge to the test. When estimating productivity, what formula do we typically use?
We use the heaped volume of the bucket adjusted by the fill factor divided by the cycle time.
Exactly! And if we consider job efficiency, how do we incorporate that into the formula?
We multiply the productivity by the job efficiency factor to get the actual productivity.
Spot on! Let’s also remember to check the suitability of the machine based on the cutting material being excavated.
That reminds me, we need to adjust for the type of material and the average height of excavation!
Great thinking! Always consider those parameters for a more accurate productivity estimation.
Introduction & Overview
Read a summary of the section's main ideas. Choose from Basic, Medium, or Detailed.
Quick Overview
Standard
The section explains how the productivity of excavation equipment, particularly shovels and backhoes, is influenced by the angle of swing and the height of cut. It outlines ideal conditions for maximizing productivity and introduces adjustment factors that must be considered in real-world scenarios, such as truck positioning and haul unit exchange times.
Detailed
In this section, we explore the concept of estimating productivity in excavation operations. Key elements affecting productivity are discussed, including the angle of swing and height of cut. The ideal angle of swing for productivity is 90 degrees, and maintaining this alongside an optimum height of cut is critical for achieving maximum efficiency. When conditions deviate from these ideals, adjustment factors—calculated based on the actual height of cut and angle of swing—must be applied to maintain accurate productivity estimations. The section also highlights the concept of truck spotting clearance and haul unit exchange time, explaining how these factors can further influence productivity by affecting the cycle time and the overall efficiency of excavating operations. Additionally, a case study illustrates the practical application of these concepts in estimating the productivity of a crawler-mounted shovel.
Audio Book
Dive deep into the subject with an immersive audiobook experience.
Truck Positioning and Angle of Swing
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
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 a 90 degree angle. The angle of swing is nothing but the horizontal angle between the digging and the dumping position between the loading and the dumping position.
Detailed Explanation
Placing the truck close to the excavator is crucial because excavators have limited mobility. A 90-degree angle between the truck and the excavator allows for optimal work efficiency because the excavator can swing its bucket to load the truck without much delay. The angle of swing defines how far the excavator has to move its bucket to transfer material from the digging site to the truck. A smaller angle means less movement and faster loading.
Examples & Analogies
Imagine a waiter serving food at a restaurant. If the waiter is standing right next to the table, it’s easy and quick to serve the food. But if the waiter is far away, he has to walk a longer distance, which takes more time. Similarly, keeping the truck close to the excavator speeds up the loading process.
Effects of Angle of Swing on Productivity
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
As the truck moves further away, your angle of swing would increase. As the angle of swing increases, you can see that your cycle time will increase, and the productivity will decrease.
Detailed Explanation
When the truck is placed farther from the excavator, the swing angle increases. This larger angle means more movement is needed for the excavator to dump the load, consequently increasing the time taken to complete each cycle (the time taken to dig, swing, and dump). This longer cycle time negatively impacts productivity because the excavator completes fewer cycles in the same amount of time.
Examples & Analogies
Think of a person throwing a ball. If they throw the ball directly in front of them, it’s quick and straightforward. However, if they have to twist and turn to throw it to someone further away, it takes much more time and effort. The same concept applies to the excavator; the more it has to swing, the less it can do effectively.
Ideal Conditions for Productivity
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
Ideal condition of shovel production is based on a 90-degree swing that is what I told you; the truck will replace it. The actual height of the cut in your project site should be the same as optimum height of cut.
Detailed Explanation
For optimal productivity, both the angle of swing and the height of cut must meet ideal conditions. The ideal swinging position (90 degrees) allows the excavator to operate efficiently, while the actual height of cut should match the optimal height set for the machine. Ensuring both these conditions are met maximizes the output and efficiency of the excavator.
Examples & Analogies
Consider a professional athlete training under perfect conditions—optimal weather, proper gear, and ideal training space. When all these factors align, the athlete performs at their best. Similarly, having the ideal conditions for an excavator leads to maximum productivity.
Adjustment Factors in Productivity Estimation
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
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, and based upon the angle of swing.
Detailed Explanation
Adjustment factors are necessary for estimating productivity when actual project conditions differ from the ideal. If the actual height of cut is lower or higher than the optimum height, or if the angle of swing varies from 90 degrees, these factors need to be accounted for to assess how they affect productivity. This ensures more accurate predictions and planning for operations.
Examples & Analogies
Imagine trying to bake a cake. If you use the wrong temperature or incorrect ingredient amounts, the cake might not rise properly or might take longer to bake. Similarly, when digging, if the machine isn’t set optimally, it affects how efficiently it can work.
Height of Cut Correction Factors
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
If the actual height of cut is the same as optimum height of cut, it means the percentage is 100%. If this percentage is going to be 100%, it means actual height of cut and optimum height of cut are the same. So, in that case, you need not apply any correction factor.
Detailed Explanation
When the actual height of cut matches the optimum height, no correction factor is needed in productivity calculations, allowing for straightforward estimates. If the height of cut is less than the optimum, it reduces productivity, prompting the application of a correction factor to adjust the estimated output.
Examples & Analogies
Think of a school assignment. If you meet all the criteria for assignment length and quality (the optimum height), then you don’t need to make changes. But if you write less or exceed the required length, you might need to adjust what you've written to ensure you meet the requirements adequately.
Angle of Swing Correction Factors
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
When the angle of swing is higher than 90 degrees, the correction factor decreases, indicating reduced productivity. If the angle of swing is less than 90 degrees, the correction factor increases, suggesting improved productivity.
Detailed Explanation
The angle of swing is directly correlated with productivity. When the swing exceeds the ideal 90 degrees, it contributes to inefficiencies, which lower productivity. Conversely, a swing angle of less than 90 degrees allows more efficient movement, thus enhancing productivity through a favorable correction factor.
Examples & Analogies
Consider riding a bicycle around a curve. If you take a sharp turn (akin to a wide swing), it’s harder to maintain speed as it requires more effort. But if you take a gentle curve (less than 90 degrees), you can keep going faster. This is similar to how an excavator performs better with smaller swings.
Truck Spotting Clearance
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
Another thing to be noted is truck spotting clearance. There should be some space left for the tail swing of the shovel.
Detailed Explanation
Truck spotting clearance is the necessary space between the truck and the excavator to allow for safe operation. The excavator needs room to swing its tail without risking collision with the truck. Maintaining this clearance is critical for safe and efficient productivity.
Examples & Analogies
Think of a large revolving door in a busy café. If people stand too close, the door won’t turn properly and can get stuck. Leaving space ensures smooth operation, just like ensuring enough clearance for the excavator tail allows for efficient loading and unloading.
Haul Unit Exchange Time
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
The time needed for the loaded truck to leave its position and for a new empty truck to take the position is called haul unit exchange time.
Detailed Explanation
Minimizing haul unit exchange time is essential because it directly affects overall productivity. If trucks are not readily available, it can cause delays and increase the cycle time for the excavator as it must wait to load the next truck. Efficient coordination of truck arrivals reduces wait times and improves productivity.
Examples & Analogies
Imagine a busy café where a new waiter needs to quickly serve new customers as fast as possible. If the previous customers take too long to leave, the new customer has to wait for their service. By ensuring smooth transitions, like promptly clearing tables, the café can serve more customers effectively.
Estimating the Productivity of the Shovel
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
Now let us see how to estimate the productivity of the shovel. The production of the shovel depends upon the heaped volume of your bucket, adjusted with the bucket fill factor, then divide it by the cycle time.
Detailed Explanation
Estimating shovel productivity involves knowing the bucket's heaped volume and adjusting it with the fill factor based on material type. Then, dividing this adjusted volume by the cycle time gives an estimate of productivity. This calculation informs how much material can be moved effectively within a certain timeframe.
Examples & Analogies
This is akin to measuring how much water you can pour from a pitcher before it runs out. If your pitcher has a certain capacity (bucket volume), and you know how fast you pour (cycle time), you can easily calculate how much you can serve in a given amount of time.
Adjusting Productivity Based on Actual Conditions
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
If the actual height of cut and angle of swing differ from the ideal condition, then you have to choose the correction factor accordingly.
Detailed Explanation
When the actual conditions deviate from the ideal setup for height of cut and angle of swing, adjustment factors must be applied to the productivity estimate. These factors correct for inefficiencies caused by less-than-optimal conditions, leading to a more accurate productivity forecast.
Examples & Analogies
Think of a car traveling in ideal conditions—smooth roads and no traffic. If it drives into a construction zone (less than optimal conditions), its speed drops, and you’d need to estimate the new time based on this slower speed compared to the ideal. Similarly, adjustments in the estimating process account for real-life challenges.
Calculating the Actual Productivity
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
Multiply the production of the shovel with the job efficiency. How much time your machine is going to work in an hour.
Detailed Explanation
To find the actual productivity, it is essential to multiply the calculated shovel production by the job efficiency factor, which reflects the actual working time in an hour. This factor accounts for downtime or inefficiencies, allowing for a more realistic estimate of productivity over an hour.
Examples & Analogies
It's like preparing food for a party. If you plan to prepare a dish in an hour but only realistically work for 45 minutes (efficiency), then you multiply the amount you can make in that time with the actual working time to understand how many servings you can prepare for your party.
Definitions & Key Concepts
Learn essential terms and foundational ideas that form the basis of the topic.
Key Concepts
-
Angle of Swing: The horizontal angle between digging and dumping positions, ideally at 90 degrees for maximum productivity.
-
Height of Cut: The vertical height at which material is being excavated, needing to match the optimum height for ideal productivity.
-
Cycle Time: The total time needed for the entire operation, from digging to dumping, critical for estimating productivity.
-
Correction Factor: Adjustments made in productivity calculations when conditions differ from the ideal values.
-
Truck Spotting Clearance: Space required to ensure safe operation without collision between equipment and trucks.
Examples & Real-Life Applications
See how the concepts apply in real-world scenarios to understand their practical implications.
Examples
-
If the angle of swing increases to 120 degrees, productivity may drop because the excavator will take longer to complete the cycle.
-
Using a bucket with a fill factor of 0.85 instead of 1 can result in a lower volume of material moved, thus affecting overall productivity.
Memory Aids
Use mnemonics, acronyms, or visual cues to help remember key information more easily.
🎵 Rhymes Time
-
For the best dig, swing at ninety, but if it's steep, productivity's empty.
📖 Fascinating Stories
-
Imagine an excavator named 'Ninety' who always digs at the perfect angle, creating a ditch in a jiffy, but if he swings too wide, he ends up taking longer, and the jobs pile up, slowing down everything.
🧠 Other Memory Gems
-
To remember the factors affecting productivity, use 'HEAT' - Height, Efficiency, Angle, and Timing.
🎯 Super Acronyms
P.A.C.E. stands for Productivity, Angle, Cycle Time, and Efficiency—key components of excavation operations.
Flash Cards
Review key concepts with flashcards.
Glossary of Terms
Review the Definitions for terms.
-
Term: Angle of Swing
Definition:
The horizontal angle between the digging and dumping positions of the excavator bucket.
-
Term: Height of Cut
Definition:
The vertical distance from the ground to the point where the material is dug.
-
Term: Cycle Time
Definition:
The total time taken for one complete cycle of digging and dumping.
-
Term: Correction Factor
Definition:
A value applied to adjust productivity calculations based on variations from ideal conditions.
-
Term: Haul Unit Exchange Time
Definition:
The time taken for a loaded truck to leave and an empty truck to arrive at the loading position.
-
Term: Job Efficiency
Definition:
The effective working time of the machine expressed as a percentage of available time.