How do you simulate the deformation of an O-ring on a shaft and bore?

3D Design Volume Model
1

Hi all!

In an assembly I have a rod that is mounted tightly in a body. On the front part of the assembly (there is my spring rod) I have an O-ring. This joint is placed in a groove between my body and the rod passes through. The goal is that when my set is mounted, the joint deforms on my rod and in my body, and a "bulge" is crushed and protrudes very slightly from the body (0.20 to 0.40 mm). I would like to simulate this deformation on SolidWorks (of the O-ring) because this function must allow a gas seal, does anyone have an idea?? :)

Thank you in advance for your feedback!!

Maxim


simulation_deformation_joint_torique.pdf
2

Is it a mechanical simulation or just a graphic simulation?

3

If it's graphic, you have to draw the joint "in context", i.e. in the assembly.

2 Likes
4

You add a config in your joint,

If the file has only one size of the toroid, and the other sizes are other files.

We then have this, and we need to add a config :

Defect (= O-ring not compressed so round)

Groove 01 (= mounting shape 01)

 

Why 01, to be able to add another type of motnage later (provident library !!)

 

And if multi configs piece, you could have:

Material - Ø020.00 x 02.65 (= O-ring not compressed so round)

Material - Ø020.00 x 02.65 Mounting 01 (= mounting shape 01)

 

And for 3D, you just have to add a material removal, then a material addition to simulate the bulge.

No need to do the join leaves, a simple representation is enough for your case.

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5

And why do a removal of material, then an addition...

The answer is: "positive construction"

 

i.e. scalable without breakage in ASM or MEP, without loss of stress.

6

Hello

Based on the principle that the deformation of the joint is done at a constant volume. It is important to check that the volume joint rest = the volume attached to the assembly mounted.

use formulas and variables to define the mounted joint section: Rest joint dimension >> joint volume >> mounted joint dimension.

Kind regards.

 

 

2 Likes
7

Thank you for the feedback!

I drew the gasket in the assembly, respecting the same volume between the gasket mounted and the gasket at rest.

The 3D modeling may not be exactly like the real "rendering" after editing, but I get a shape ("bulge") that protrudes from my body. I can start from there to do my tests!!

Thanks again!

8

As it is a joint, it crushes a little, it is soft,

so the "mounted section" = 0.98 or 0.95 x "free section"

 

Something like that, right?

9

Knowing that there are point contact areas (poncutel pressure), the joint will have a potato shape so "mounted section" = 0.98 or 0.95 x "free section" cannot be applied.

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I don't think that's what fbourggeaux is looking for, because negligible in his case.

 

But I think that there is still a compression, I'm not talking about the "throat", the fact that there is a point compression.

So the free or mounted section is not the same, there is necessarily a compression coef due to a soft material, even if it is tiny.

11

Hello

I don't understand and a bulge is created.

What is the point of simulating the shape of the mounted seal, to ensure the tightness it is enough to

Observe the tolerances of the groove and the fit given by the gasket manufacturer.

Kind regards.

1 Like
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The manufacturer does give a standard diemsion in which the O-ring will be positioned. In my case, I want the waterproofing to be done both on the shaft but on the face... and there the manufacturer doesn't give anything (because basically, the gasket is not made for that) ... The simulation of my "bulge" is only used to position my throat (to give a length between my face and my throat)

13

yes there is understanding in all cases

Before, during and after travel

but even in the rest position otherwise no sealing

See these links

https://www.parker.com/literature/Praedifa/Catalogs/Catalog_O-Ring-Handbook_PTD5705-FR.pdf

http://nuxeo.edel.univ-poitiers.fr/nuxeo/site/esupversions/f01e42e8-37d9-4ca6-9034-771acaa63c45

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To be seen according to the pressures and fluids involved, but I have a doubt about the effectiveness of the assembly: the groove limits the possibility of deformation and ensures the contact force between the surfaces. In this assembly, the joint has the possibility of deforming without limit.

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see attached

image taken from this link

https://www.parker.com/literature/Praedifa/Catalogs/Catalog_O-Ring-Handbook_PTD5705-FR.pdf

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