Moment of intertia for corrugated pipes

• square_1
In summary, Aktan is looking for a formula for the moment of inertia for corrugated hollow pipes, which are made up of a solid main pipe and a smaller diameter hollow plastic pipe. They need this information to calculate the pipe's stiffness and deflection under a given load. The usual method is to calculate the unit moment of inertia and approximate it based on the inner tube and use parallel axis theory to combine. This data is typically found in published tables for commercially produced pipes.
square_1
Hi,

I am struggling to find forumula for Moment of Inertia for corrugated hollow pipes somewhat as shown in the picture.

Main Pipe is made of Solid wall construction over which smaller diameter hollow plastic pipe is spairally welded.

Any approximate calculations will also help. Thanks, Aktan

That's a bellows that's designed to be flexible, why do you want a MOI for it?

Mech_Engineer said:
That's a bellows that's designed to be flexible, why do you want a MOI for it?

Yes , we have flexible corrugated plastic pipes somewhat similar to given in picture. I require MOI to calculate pipe stiffness, that will be used further to calculate pipe deflection under a given load.

Thanks

Normally you'd just calculate the a unit moment of inertia, in^4/in and depending on how perfect you want the value, you either approximate it as the inner tube if it is a simple pipe with the corrugations applied to the outside as stiffeners, and use parallel axis theory to combine. Most commerically produced pipe have tables published with all this data.

http://www.dot.ca.gov/hq/esc/techpu...idge-design-specifications/page/section12.pdf

Hello Aktan,

The moment of inertia for corrugated pipes can be calculated using the following formula:

I = (π/64) x (D^4 - d^4)

Where:
- I is the moment of inertia
- π is the mathematical constant pi
- D is the outer diameter of the main pipe
- d is the outer diameter of the smaller hollow pipe

This formula assumes that the corrugated pipe is circular in shape. If the corrugations are not uniform or the shape is irregular, the moment of inertia can be calculated by dividing the pipe into smaller sections and using the parallel axis theorem.

It is important to note that this formula provides an approximate calculation and may not be accurate for all corrugated pipe designs. It is always best to consult with the manufacturer or a structural engineer for more precise calculations.

I hope this information helps. Best of luck with your project!

Best,

1. What is the moment of inertia for corrugated pipes?

The moment of inertia for a corrugated pipe is a measure of its resistance to changes in rotational motion. It is a property that depends on the size, shape, and distribution of mass of the pipe.

2. How is the moment of inertia calculated for corrugated pipes?

The moment of inertia for corrugated pipes can be calculated using the equation I = ∫r²dm, where r is the perpendicular distance from the axis of rotation to a small element of mass dm. This integral is usually solved using the parallel axis theorem, which takes into account the distribution of mass along the length of the pipe.

3. What factors affect the moment of inertia for corrugated pipes?

The moment of inertia for corrugated pipes is affected by the diameter, wall thickness, and corrugation pattern of the pipe. Additionally, the material properties, such as density and elastic modulus, can also impact the moment of inertia.

4. How does the moment of inertia impact the performance of corrugated pipes?

The moment of inertia plays a crucial role in determining the structural integrity and stability of corrugated pipes. Pipes with a higher moment of inertia are more resistant to bending and buckling, making them suitable for use in applications where they may be subject to external loads or forces.

5. Can the moment of inertia be adjusted for corrugated pipes?

Yes, the moment of inertia for corrugated pipes can be adjusted by changing the dimensions and material properties of the pipe. For example, increasing the wall thickness or using a denser material can increase the moment of inertia, making the pipe stronger and more resistant to deformation.

Replies
7
Views
3K
Replies
15
Views
2K
Replies
2
Views
3K
Replies
1
Views
2K
Replies
5
Views
2K
Replies
4
Views
2K
Replies
1
Views
3K
Replies
2
Views
4K
Replies
14
Views
7K
Replies
1
Views
2K