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.
Angle of Swing and Truck Placement
Unlock Audio Lesson
Today, we're discussing the concept of angle of swing. Can anyone tell me what happens to productivity if the truck is placed at an angle greater than 90 degrees?
I think productivity decreases as the angle gets larger?
That's correct! The larger the swing angle, the longer the cycle time, which directly impacts productivity. Remember, we want to keep it at 90 degrees when possible!
So having the truck really close to the excavator is the best way?
Exactly! Keeping the truck close minimizes the angle and keeps the cycle times short, thereby enhancing productivity. We can think of the acronym 'PACE'—Positioning And Cutting Efficiency.
What about when the angle is less than 90 degrees?
Good question! If the angle is less than 90 degrees, the correction factor actually increases, which can help improve productivity!
So, to summarize, we want an angle of swing around 90 degrees to keep our productivity high?
Exactly! Great recap, everyone.
Height of Cut and Correction Factors
Unlock Audio Lesson
Let's move on to the height of cut. Why is it important to maintain the actual height of cut similar to the optimum height?
If it’s not the same, it could lower productivity?
Exactly! If the actual height is less or greater than the optimum height, we need to apply correction factors which reduce productivity.
How do we calculate this percentage?
We take the actual height divided by the optimum height and multiply by 100. For example, if the actual height is 3.18 meters and the optimum height is 5.3 meters, what do we get?
That would be about 60%.
Correct! This is key because if the height is not optimal, we have to adjust downwards our productivity estimates.
Estimating Shovel Productivity
Unlock Audio Lesson
Now, let's apply what we’ve learned by calculating productivity. What formula do we use?
Is it the bucket's heaped volume divided by cycle time?
Yes! We also need to adjust by the fill factor and any correction factors we discussed. If we have a bucket volume of 3.44 cubic meters, and the cycle time is 24 seconds, what is the ideal production per hour?
It’s...469.56 loose cubic meters per hour!
Fantastic! That’s the impact of correctly applying these factors. Always remember to keep job efficiency in mind too!
Introduction & Overview
Read a summary of the section's main ideas. Choose from Basic, Medium, or Detailed.
Quick Overview
Standard
The section examines the significance of various operational factors in the productivity estimation of shovels and discusses optimal angles for efficiency. Key topics include the influence of truck placement, the correction factors based on height of cut and angle of swing, and details on estimating shovel productivity.
Detailed
Problem Example on Production Estimation
In construction and excavation operations, productivity estimation is vital for planning and executing projects efficiently. This section outlines several key factors that significantly affect production rates, specifically focusing on the positioning of trucks relative to excavators, the angle of swing during operation, and the height of cut of the material being excavated.
Key Factors:
- Truck Placement: The proximity and positioning of trucks to excavators are crucial for optimizing cycle times. Ideally, trucks should be positioned at a 90-degree angle to the excavator's swing. As this angle increases beyond 90 degrees, productivity typically decreases due to longer cycle times.
- Height of Cut:
- The actual height of cut must align with the optimum height for maximum productivity. This alignment is crucial as it influences the correction factors applied to productivity calculations. If the actual height is less than or greater than optimal, correction factors decrease productivity.
- To determine the optimum height, it is generally a percentage (30% to 50%) of the maximum digging height of the machine, contingent on the material type.
- Correction Factors:
- These are used to adjust productivity estimates based on the height of cut and angle of swing. An ideal condition does not require corrections, while deviations necessitate calculating and applying specific factors.
- Haul Unit Exchange Time: This refers to the time taken for a truck to drop off a load and return for another round. Minimizing this time is critical as waiting trucks can hinder productivity.
- Calculating Productivity: The overall productivity can be calculated based on factors such as heaped bucket volume, cycle time, and adjusted for job efficiency, swing depth factor, and correction factors.
Through examples, this section provides insight into practical calculations for estimating shovel productivity, essential for anyone involved in planning excavation operations.
Audio Book
Dive deep into the subject with an immersive audiobook experience.
Truck Placement 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 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. As the truck moves further away, your angle of swing would increase as the angle of swing increases. As the angle of swing increases, you can see that your cycle time will increase, the productivity will decrease.
Detailed Explanation
In this chunk, we discuss the optimal placement of a truck in relation to an excavator. The ideal angle of swing is 90 degrees, meaning the truck is directly next to the excavator. If the truck is positioned further away, the angle of swing increases, leading to longer cycle times and decreased productivity. Essentially, the cycle time refers to how long it takes for the excavator to dig, swing, and dump the material. When the truck is too far, the machine has to swing more, which takes extra time and reduces the number of cycles it can perform in an hour.
Examples & Analogies
Think of it like playing a game of basketball. If the hoop is right in front of you, it's easy to shoot the ball directly into it. But if you have to take a few steps back and shoot from farther away, it takes more time to aim and shoot, and you're likely to miss more often. Therefore, keeping the hoop close (or in this case, the truck) allows for more successful 'shots' (or work) in the same amount of time.
Adjustment Factors for 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 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. So, adjustment factors for the height of cut and the angle of swing for the shovel. If the actual height of cut is same as optimum height of cut, it means the percentage is 100%.
Detailed Explanation
In this chunk, we introduce adjustment factors that influence productivity estimates. These factors account for variations in the actual height of cut and the angle of swing, relative to the ideal conditions. The optimum height of cut is essential for determining how effective the machine will be. If the actual height matches the optimum height (which is considered 100%), then no adjustment is necessary. However, if the actual height differs from the optimum, like being less or greater than that, productivity will be impacted, and we need to apply a correction factor to adjust estimates accordingly.
Examples & Analogies
Think of baking a cake. If you have exactly the right amount of ingredients, your cake will come out perfectly (100% efficiency). But if you either use too little flour (which makes it collapse) or too much (which can make it rise unevenly), the final cake won’t be as good. Similarly, achieving the 'right balance' of height and angle for the excavator ensures optimal performance, just like your cake needs the right proportions to taste good.
Correction Factor Application
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
For the angle of swing, when the angle of swing is more than 90 degree, you can see that the correction factor is reducing, it shows that your productivity will reduce, but if your angle of swing is lesser than 90 degree, you can see that the correction factor is increasing. That means it shows that your productivity is increasing.
Detailed Explanation
Here, we focus on how the angle of swing affects productivity. If the angle exceeds 90 degrees, the correction factor decreases, indicating reduced productivity – the machine takes longer to swing to dump material. Conversely, if the angle is less than 90 degrees, the correction factor increases, suggesting higher productivity. This means that achieving a swing angle smaller than the ideal allows the machine to work more efficiently, reducing cycle times.
Examples & Analogies
Imagine a dancer doing a turn. The more they turn, the longer it takes for them to face the audience again. If they keep their turn small, they can face forward much more quickly and smoothly. In excavation, just like in dance, keeping the swing tight improves performance.
Estimating Shovel Productivity
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 shovel depends upon the heaped volume of your bucket, heaped volume of your bucket you can get it from the manufacturer, that you are going to adjust with the bucket fill factor, depending upon your material type, then divide it by the cycle time.
Detailed Explanation
This chunk explains the process of estimating shovel productivity. The productivity is initially calculated based on the heaped volume of the bucket, which is provided by the manufacturer. This volume must be adjusted by a bucket fill factor – this is based on the material being handled (for example, gravel might fill the bucket differently than heavy rocks). Finally, this adjusted volume is divided by the cycle time to determine how much material can be moved in an hour.
Examples & Analogies
Imagine you are filling up a backpack to carry items. The backpack has a set capacity (like the shovel bucket volume). However, if you try to pack it with soft pillows, you might fit more than if you were trying to fit hard books. The fill factor is like considering how well you pack it, and the time it takes to pack and carry the backpack is akin to the cycle time for the shovel.
Production Estimation Problem Example
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
Now let us work out a problem on the production estimation a crawler mounted shovel with a heaped bucket capacity of 3.44 meter cube is loading a well blasted rock. The bucket fill factor can be taken as 1, depending upon the material type, they are supposed to take the bucket fill factor, it is readily given to you in this question as 1. It is working at 3.18 meter high face.
Detailed Explanation
This chunk introduces a practical problem for estimating production. It describes a crawler-mounted shovel that has a specific bucket capacity and fill factor and notes that it is operating at a specific height. Here, students can learn to apply the principles of productivity estimation by plugging in the values for bucket capacity, the fill factor, and cycle time to arrive at an estimate for shovel productivity in real-world scenarios.
Examples & Analogies
Think of this as a math problem, where you have a recipe that uses exact measurements. Just like cooking, if you know the amount of ingredients (bucket capacity), how well you can mix them (fill factor), and how long you'll take to prepare the dish (cycle time), you’ll end up with a final dish (productivity) that you can quantify.
Definitions & Key Concepts
Learn essential terms and foundational ideas that form the basis of the topic.
Key Concepts
-
Ideal Production: Refers to the maximum production capacity of a shovel when operating under perfect conditions, including 90-degree swing and optimal height of cut.
-
Correction Factors: Adjustments applied to account for variances from ideal conditions to estimate real productivity.
-
Cycle Time: The total time it takes to complete a loading cycle, significantly influencing productivity.
Examples & Real-Life Applications
See how the concepts apply in real-world scenarios to understand their practical implications.
Examples
-
If a truck is positioned at a 70-degree angle instead of 90 degrees, the productivity will likely decrease due to longer cycle times.
-
A shovel working at an actual height of cut of 3.18 meters, when the optimum height is determined to be 5.3 meters, will operate at 60% effectiveness.
Memory Aids
Use mnemonics, acronyms, or visual cues to help remember key information more easily.
🎵 Rhymes Time
-
For the best swing, keep it at ninety, it makes loading feel quite light and plenty.
📖 Fascinating Stories
-
Imagine a truck and excavator at a perfect angle. Their dance is efficient, maximizing production with each swing.
🧠 Other Memory Gems
-
Use 'SOAR' to remember: 'Swing Optimize Angle Ratio' for maximizing productivity.
🎯 Super Acronyms
PACE
- Positioning And Cutting Efficiency shows how to enhance effectiveness in machinery operation.
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 bucket during excavator operation.
-
Term: Correction Factor
Definition:
A numerical adjustment applied to productivity estimates based on the actual height of cut or swing angle.
-
Term: Height of Cut
Definition:
The distance from the ground to the cutting edge of the bucket, which should ideally match the optimum height for optimal productivity.
-
Term: Haul Unit Exchange Time
Definition:
The duration necessary for a loaded truck to leave and an empty truck to take its place for loading.