5.2 - Next Steps
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Understanding Scraper-Pusher Dynamics
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Today, we're going to discuss how the number of scrapers affects production control and why understanding this relationship is crucial for efficient operations.
Why does the number of scrapers matter in production control?
Great question! When you have fewer scrapers than needed, they become critical, meaning they control the production rate since a pusher will have the ideal time, waiting for scrapers. If scrapers are more than the needed number, the pusher controls the output.
What happens if we increase from 5 to 6 scrapers?
Increasing from 5 to 6 scrapers increases productivity; for instance, the production rate rises from 636.89 to 723.36 bank cubic meters per hour. Remember, a primary decision is whether to focus on productivity or minimize costs.
So it's a balance between efficiency and cost?
Exactly! Balancing these factors is key. We should remember the acronym 'PESCO' - for **Production, Efficiency, Scraper count, Cost, Output**.
What about the costs involved?
That leads to unit production costs, which we’ll cover in the next session. Let’s summarize: fewer scrapers mean they control production; more scrapers, the pusher controls output.
Calculating Production Output
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In our last session, we completed our discussion on scraper and pusher dynamics. Now, let’s dive into calculating production outputs.
How do we calculate the production for scrapers?
The formula involves the cycle time of the scrapers and the volume of load per scraper. For instance, with 5 scrapers, we get a production of 636.89 bcm/h.
Can I see an example calculation?
Certainly! We take the volume per load of 19.82 bcm, apply the scraper cycle time of 7.78 minutes, and also consider job efficiency at 50 minutes. The calculation shows how productive we can be with that configuration.
And if we switch to 6 scrapers?
Good observation! Switching to 6 scrapers increases production, demonstrating the effect of changing variables on outputs.
What should I remember from this?
Remember the formula: **Production = (Num of Scrapers × Volume per Load) / Cycle Time**. Each calculation adds a real-world perspective to our estimations.
Analyzing Unit Production Costs
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Now, let’s explore unit production costs. Why is it important?
To figure out which deployment option is more cost-effective?
Exactly! We calculate unit costs by dividing the total hourly cost of both scrapers and pushers by productivity. For example, using the configuration of 5 scrapers results in ₹44.12 per bcm.
How does this change with 6 scrapers?
It changes to ₹45.07 per bcm—so despite better productivity, costs rise. Therefore, it’s essential to evaluate both factors.
Should I prioritize cost over productivity?
Not always; it's context-dependent. Always ask: 'What is my project’s priority?' Let’s remember 'C-PAP: Cost, Priority, Assessment, Production'.
Got it! Cost is just one part of the equation.
Exactly! And that's our takeaway today.
Introduction & Overview
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Quick Overview
Standard
In this section, the analysis of productivity related to utilizing scrapers in varying quantities is explored. It compares the production output achieved with different configurations—specifically focusing on the production cost per bank cubic meter for both low (5 scrapers) and high (6 scrapers) configurations.
Detailed
Next Steps
This section transitions into analyzing the economic aspects of utilizing scrapers in construction or mining operations, particularly emphasizing the productivity of scrapers based on their numbers in relation to a single pusher.
Key Points
- Scraper and Pusher Dynamics: The relationship between scrapers and pushers is discussed, emphasizing that when the available scrapers are fewer than needed (like in the case of 5), they become critical in controlling production. If there are more scrapers (like in the case of 6), they become less critical, and the pusher then dictates the production rate.
- Production Calculations: The production output for different configurations is calculated using the formula that incorporates the number of scrapers, load volume, and equipment cycle times:
- When using 5 scrapers, productivity results in 636.89 bank cubic meters per hour, while switching to 6 scrapers achieves 723.36 bank cubic meters per hour.
- Unit Production Cost: The cost of production per bank cubic meter is carefully analyzed. The comparison demonstrates that the configuration of 5 scrapers and 1 pusher leads to a minimum unit production cost of ₹44.12 per bank cubic meter as opposed to ₹45.07 when 6 scrapers are utilized.
- Decision Making: The decision on the number of scrapers utilized hinges between maximizing productivity for tight timelines versus minimizing costs, leading to a clear recommendation for contractors or decision-makers in excavating operations.
- Further Analysis: Future considerations involve estimating rimpull to confirm the scraper's operational capability against the job requirements, necessary for optimizing heavy machinery use.
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Overview of Scraper Production Economics
Chapter 1 of 5
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Chapter Content
Now let us consider the economics of going for 5 scrapers. So, 5 in the sense you are going to use lesser than what is needed, you are assuming 5 that means you are going to use the number of scrapers lesser than what is needed. So, when the number of scrapers are lesser than the balanced number so obviously scrapers are more critical, but a pusher will have the ideal time. Your pusher will wait for the scraper.
Detailed Explanation
In this section, we assess the economic implications of utilizing 5 scrapers, which is fewer than the ideal number. Utilizing fewer scrapers leads to an imbalance in the production line where scrapers become the bottleneck; they are more critical in determining output since their limited availability delays the process. Meanwhile, the pusher, responsible for assisting the scrapers, will have a lot of idle time as it waits for scrapers to become available.
Examples & Analogies
Imagine a train system where fewer locomotive engines are used than required. The trains (pushing vehicles) are ready to transport goods, but they cannot start until the freight cars (scrapers) are attached. If there are not enough freight cars to meet demand, the system is slowed, causing delays.
Productivity Calculation for 5 Scrapers
Chapter 2 of 5
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Chapter Content
So, now, let us see the productivity this case of n equal to 5 scrapers. How to estimate the production of this scraper? The volume of your bowl volume per load, you know the value of 19.82 bank cubic meter. Production (Scraper controlling) = (Efficiency, hr) × (no. of scrapers) × (vol. per load) / (Cycle time of scraper, min)
Detailed Explanation
To calculate the productivity of 5 scrapers, we take into account their efficiency and the volume they can hold per load. The production formula uses the effective working efficiency of the scrapers, which multiplies the number of scrapers (5 in this case) by the volume per load (19.82 bank cubic meters) and divides by the cycle time of the scrapers.
Examples & Analogies
Consider a chef who can only make five pizzas at a time in an oven. If it takes him 30 minutes to bake one set of five pizzas, you can calculate how many pizzas he can churn out in an hour by using that time efficiently. The idea is similar; we’re balancing the time it takes to work against how much we can produce.
Comparison with 6 Scrapers
Chapter 3 of 5
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Chapter Content
If n is greater than the balance number that means you are going to use more number of scrapers, then what is indicated by the balance number. In this case, scrapers will have the ideal time. Scrapers are not critical.
Detailed Explanation
When the number of scrapers exceeds the optimal count, the dynamics shift. In this case, scrapers enjoy more idle time since they don’t have as much work to do compared to the pusher, which becomes critical in maintaining production flow. This scenario generally reduces overall effectiveness.
Examples & Analogies
Think of a soccer team where you have too many players on the field compared to the allowed amount. Some players are left unutilized while others are trying to work too hard to manage the game. The imbalance leads to inefficiencies in teamwork.
Unit Production Cost Estimation
Chapter 4 of 5
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Chapter Content
We need the unit production cost in terms of the cost per bank meter cube. That is why we have to estimate the production also in the bank cubic meter. So, it is already estimated earlier the volume per load that is a volume of the bowl is 19.82 bank cubic meter.
Detailed Explanation
Calculating the unit production cost is essential for evaluating the economic feasibility of using scrapers. The cost must be expressed in terms of bank cubic meters, ensuring we understand the efficiency of the operation in financial terms. The volume of each load remains crucial in this calculation.
Examples & Analogies
Suppose you run a lemonade stand and your production costs consist of lemons, sugar, and water. To understand the profitability of your operation, you’ll need to figure out how much you're spending per cup of lemonade based on how many cups you can make from the ingredients. This is similar to calculating the cost for bank cubic meters.
Final Decision Making
Chapter 5 of 5
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Chapter Content
If you are more concerned about the productivity, if you have very tight deadlines, you have to finish the project faster. In that case people prefer to go for the combination which gives you higher productivity, but very often we see that people are more concerned about the cost only.
Detailed Explanation
Decisions regarding the number of scrapers to use depend heavily on company priorities, such as productivity vs. cost efficiency. If deadlines are not tight, operators may lean towards options that lower costs, even if that means potentially sacrificing output rate. Conversely, when time constraints are pressing, maximizing productivity becomes the priority.
Examples & Analogies
Think of a restaurant where a chef must complete meals for a large event quickly. If time is of the essence, he may hire additional cooks to increase meal production even if it means spending more. However, if time is less critical, he may opt for a smaller team to save on labor costs.
Key Concepts
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Scraper-Pusher Productivity Dynamics: Scrapers control production when in short supply, pushers when oversupplied.
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Unit Production Cost: Costs of scrapers and pushers must be evaluated against production output for efficiency.
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Production Rates: Calculated based on the number of scrapers, volume per load, and cycle times.
Examples & Applications
Using 5 scrapers results in a productivity rate of 636.89 bcm/h, while 6 scrapers yield 723.36 bcm/h.
The unit cost for 5 scrapers is calculated as ₹44.12 per bcm, while for 6 scrapers, it's ₹45.07.
Memory Aids
Interactive tools to help you remember key concepts
Rhymes
When scrapers less are in the race, they drive production at a pace.
Stories
Imagine a race where scrapers are horses. If you have fewer, they push harder; with many, the pusher takes the lead.
Memory Tools
Remember 'SPECS' - Scraper-Pusher Efficiency Cost Structure.
Acronyms
PESCO - Production, Efficiency, Scraper count, Cost, Output.
Flash Cards
Glossary
- Scraper
A heavy construction vehicle utilized to move earth, having a horizontal loading auger-controlled by a pusher.
- Pusher
A type of vehicle that provides additional force to scrapers, helping them load and transport material.
- Production Efficiency
A measure of how well resources (scrapers and pushers) are utilized to achieve maximum output.
- Bank Cubic Meter (bcm)
A unit of volume measurement used in excavation to quantify the amount of earth moved.
- Unit Cost
The cost incurred to produce one bank cubic meter of material.
Reference links
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