Topic Options
#72052 - 08/22/18 07:12 AM Issues modeling elbows near restraints
ruiDiogo Offline
Member

Registered: 08/17/18
Posts: 6
Loc: Portugal
Hello all,

I'm fairly new to CII, so please bear with me. I'm having trouble modeling elbows that are near restraints. Visually, there seems to be enough space to model said bends, so I can't figure out what it is I'm doing wrong.
Please see attached images for more details on this issue.

Thanks for the help.

PS: The element dimensions are based on actual field, measurements, so extending or shrinking one of the elements isn't really an option.


Attachments
1.png

Description: General view

2.png

Description: Detailed view before adding bend

4.png

Description: Detailed view after adding bend

6.png

Description: Bend data



Top
#72058 - 08/23/18 07:19 AM Re: Issues modeling elbows near restraints [Re: ruiDiogo]
Richard Ay Offline
Member

Registered: 12/13/99
Posts: 6226
Loc: Houston, Texas, USA
It would be better to send your model in so we can look at it. Either attach it here or file an SR on Smart Support.
_________________________
Regards,
Richard Ay - Consultant

Top
#72063 - 08/24/18 04:23 AM Re: Issues modeling elbows near restraints [Re: Richard Ay]
ruiDiogo Offline
Member

Registered: 08/17/18
Posts: 6
Loc: Portugal
Thank you for replying, Richard.
Please find attached a simplified version of my problem - you can see the elbows are badly warped.

Regards,

Rui


Attachments
BEND_TEST.C2 (485 downloads)



Edited by ruiDiogo (08/24/18 04:24 AM)

Top
#72065 - 08/24/18 07:54 AM Re: Issues modeling elbows near restraints [Re: ruiDiogo]
Dave Diehl Offline
Member

Registered: 12/14/99
Posts: 2382
Loc: Houston, TX, USA
I believe it's something on our end. The output plot shows the bends as you would expect.

You have quite a family of skewed pipe and I also notice some interesting units selection. I would like to see your .fil (units) file.

I threw in a regular old 90 degree in your model and it shows up fine:


Attachments
8-24-2018 8-49-43 AM.png


_________________________
Dave Diehl

Top
#72071 - 08/27/18 07:00 AM Re: Issues modeling elbows near restraints [Re: ruiDiogo]
Richard Ay Offline
Member

Registered: 12/13/99
Posts: 6226
Loc: Houston, Texas, USA
This is simply a numeric precision problem with the graphics. When plotting bends (or anything else), all data is being converted into LENGTH units (OD, Bend-Radius, etc.). This may make some small/decimal values. All graphics calculations for bends are single-precision (and rounded). In addition, this job is skewed from the global coordinate system, which adds to precision issue by generating very small off axis values.

There is nothing wrong with this model. One thing you could try is to use the option "Convert Model to New Units", and pick a units system where LENGTHs are in mm, Compound_Length is in M. (The OD can stay in cm if you want.) The model should plot correctly then.
_________________________
Regards,
Richard Ay - Consultant

Top
#72072 - 08/27/18 08:48 AM Re: Issues modeling elbows near restraints [Re: ruiDiogo]
Michael_Fletcher Offline
Member

Registered: 01/29/10
Posts: 1025
Loc: Louisiana, US
You could shift the support by some fraction of a length, if the problem is rounding error.

If your elbow is welded in, however, it might not be such a good idea to put a support at the weld.

Top
#72081 - 08/28/18 03:18 AM Re: Issues modeling elbows near restraints [Re: ruiDiogo]
ruiDiogo Offline
Member

Registered: 08/17/18
Posts: 6
Loc: Portugal
Dear Dave, Richard and Michael,

Thank you for your quick and thoughtful responses.

Dave, I've attached to this message my .fil units file. Had I known it could warp my geometry, I would have been more careful in creating it, but since my topographical data was in m, I figured it would just be simpler this way.

Richard, I'll try your approach and let you know if it did the trick, thanks.

Michael, I'm actually working on a pipeline that's already out in the field, so fiddling around with the supports won't do me any good.


Attachments
UNITS.FIL.C2 (450 downloads)


Top
#72082 - 08/28/18 03:29 AM Re: Issues modeling elbows near restraints [Re: ruiDiogo]
ruiDiogo Offline
Member

Registered: 08/17/18
Posts: 6
Loc: Portugal
Hey again,

So it turns out Richard's right, switched it to mm, no more glithcy bends.

Thanks a lot, appreciate all your help!

Top



Moderator:  Denny_Thomas, uribejl 
Who's Online
0 registered (), 55 Guests and 0 Spiders online.
Key: Admin, Global Mod, Mod
April
Su M Tu W Th F Sa
1 2 3 4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30
Forum Stats
12065 Members
14 Forums
16973 Topics
75151 Posts

Max Online: 303 @ 01/28/20 11:58 PM
Top Posters (30 Days)