Configuration for hangers

Posted by: Kristina_BET

Configuration for hangers - 02/21/17 05:57 AM

Hello!
While modeling a pipeline DN500 (508x36), distance between supports should be around 9m at 200oC. If I let Caesar choose a hanger (undesign) it chooses constant hanger for vertical movement 10mm?? We use LISEGA hanger table, so the limit between constant and variable hangers is 40-50mm for vert.movement.
How can I change this option limit?
Thank you,
Kristina
Posted by: Michael_Fletcher

Re: Configuration for hangers - 02/21/17 02:04 PM

CAESAR is telling you that there is no LISEGA standard spring that meets all the qualifications set out by the vendor for your configuration. Generally, this means there is too much variation in spring load (Lisega requires a range of 25% from operating), etc.

Move your springs around, or add flexibility so your pipe doesn't grow vertically so much.
Posted by: Dave Diehl

Re: Configuration for hangers - 02/21/17 04:24 PM

Kristina,

What is the displayed "Hot Load" and the "Vertical Movement" for this hanger location?
My guess is that you have included a very small "Allowable Load Variation" in your hanger selection criteria.
Posted by: Kristina_BET

Re: Configuration for hangers - 02/24/17 02:28 AM

Thank you Michael and thank you Dave!

Yes Dave, allowable load variation was set on 20%.
As Prog. Design, Caesar chooses constant hanger for 14kN and -47 mm vert.movement. I know, as a designer I can change the type of hanger by inserting theoretical cold load and it will be changed into variable spring hanger.
When I change it as it was by default (25%) it gives me VSH.
My question is - Is there a way for setting this limit in configuration settings?
As the LISEGA catalog has this limit for VSH - maximum travel of 50mm!

Thank you.
Kristina
Posted by: Dave Diehl

Re: Configuration for hangers - 02/24/17 08:49 AM

I am unsure of the question here.
You can change the default load variation limit (from 25%) in the model's Hanger Control Data.Set this before you enter a hanger to be sized and your new load variation limit will appear as part of your design data. See below.
Also, you can push CAESAR II to select a constant effort hanger if the change in position is greater than a specific value, e.g., 50mm. See below.