×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

O-ring groove design
2

O-ring groove design

O-ring groove design

(OP)
Hello everyone,

I'm often in a position where I have to design O-ring grooves for different compressed gas applications. Radial static installation, radial dynamic installation, axial installation, dovetail grooves, half-dovetail grooves, you name it. Trelleborg and Parker handbooks are good resources in combination with industry experience.

Now, another configuration is what I guess you can call an angled seal(?) configuration. Quick example below (blacked-out part is the O-ring to indicate placement). The groove can be both a typical "square" configuration (as shown on the image below), or as half dovetail groove. The angle of orientation usually lies between 60° and 90°.



My question is this: Does any design handbooks cover this specific configuration? I know certain standards describe specific grooves for specific O-ring sizes for these configurations (e.g. ISO 5145 & CGA V-1), but not nearly as extensively as the other more common configurations. I usually deal with O-rings with a cross section between 1.78-2.4 mm, with an inside diameter <20 mm, so the stretch range is usually a bit wider than the typically recommended 2-8 %.

Don't get me wrong, I have designed these before, with no issues, by using common sense. I'm simply wondering if any handbooks cover this topic, as I've yet to find any that does.

Thank you for any input you may have.

RE: O-ring groove design

The handbooks prescribe the amount of squeeze the o-ring should get and gland surface finish to seal properly. Design around that information. The gland will then become what it needs to be. Also consider the means to create the gland.

Ted

RE: O-ring groove design

(OP)
Yes, that is pretty much what I gathered, guess I will just keep tabulating existing designs as I make them. The hardest (and costliest) part of the process is without a doubt the machining of such grooves, but hey, what the customer wants the customer gets...

RE: O-ring groove design

Unfortunately there are no standards for conical sealing. O-ring being round in Shape, after assembly need to have same squeeze / fill in these type of grooves too.
Only concern here, as you rightly mentioned is size selection. In these cases I would prefer to go for O-ring ID size either equal to or preferably 1%~2% larger than the lower groove dimension so when the pressure in system acts it fills the free area in groove and energize the O-ring to give good sealing.

Thanks

RE: O-ring groove design

(OP)
Sealing guy:

Correct, a proper squeeze is important. Parker's recommendation of minimum 0,2 mm compression holds up even for higher pressure ratings.
Certain applications involving sealing against a cylinder valve outlet have weird standards, AFNOR NF 29-650 being one of them. The O-ring gland doesnt have enough room and the O-ring is therefore slightly extruded. This is compensated for by using 93 ShA Zurcon O-rings, as they are very well suited for these applications, and for pressures upwards to 400 bar (cylinder pressure).

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close