# Balancing a shaft using mrL and mr vectors

• ridiculoid
In summary, the problem involves calculating the mass and diameter of a flywheel given a known angle and volume. The equations used are trigonometry equations, p=m/v, and A = pi * d^2 / 4. After working through the problem, the mass is calculated to be 9.318kg at an angle of 150° from point A, and the diameter is found to be 0.235m. The individual seeking help is unsure if they followed the correct procedure and is looking for clarification and assistance in understanding the problem. It is advised to solve the problem algebraically and to use variable names and standard equations, as well as providing a web link for unfamiliar concepts.

## Homework Equations

Trigonometry equations, p=m/v, A = pi * d^2 / 4

## The Attempt at a Solution

i) mass calculated is 9.318kg at 150° from A

ii) diameter = 0.235m

I apologize for the messy working, I am just wondering if I have followed the correct procedure or not. The end diameter seems quite large, I may be misinterpreting the question though as the flywheel is initially large as well.

Any help would be greatly appreciated.

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ridiculoid said:
I apologize for the messy working
Don't apologize, fix it. Likely no-one will make the effort to follow it as is.

Work it through purely algebraically. Assign variable names to the distances etc., not plugging in any numbers. I'll make an exception for the 120 degree angles. Take the trouble to type it in and quote any principles or standard equations you are using. Maybe there is some web link you could post for any unfamiliar with the topic.

Last edited:
berkeman

## 1. What is mrL and mr vectors?

mrL and mr vectors are mathematical representations used in shaft balancing to describe the magnitude and direction of unbalance forces.

## 2. Why is balancing a shaft important?

Balancing a shaft is important because it helps improve the performance and lifespan of rotating machinery. Unbalanced forces can lead to excessive vibrations, which can cause damage to the shaft and other components.

## 3. How do you calculate mrL and mr vectors?

mrL and mr vectors can be calculated using specialized equipment such as a balancing machine or vibration analyzer. These tools measure the unbalance forces and calculate the magnitude and direction of the vectors.

## 4. What is the purpose of using mrL and mr vectors in shaft balancing?

The use of mrL and mr vectors allows engineers to accurately determine the amount and location of unbalance in a shaft. This information is used to determine the corrective measures needed to achieve proper balance.

## 5. Can balancing a shaft using mrL and mr vectors eliminate all vibrations?

No, balancing a shaft using mrL and mr vectors can reduce vibrations to an acceptable level, but it cannot eliminate them completely. Other factors such as shaft misalignment or bearing wear can also contribute to vibrations.