2 replies to this topic

[J_Leo]

Dear All,

I am working on the Hydaulic Check of a refinery unit. There are some eccentric reducers on the piping. We have some equations for the concentric reducers which using an angle THETA. Can we just calculate the angle THETA for eccetric reducers and use the same equations to caculation the pressure drop?

Or if we can use the the pressure drop for a concentric reducer with the same size (ex. 6"x4") as the pressure drop through an eccentric reducer (6"x4")?

Thank you very much.

Leo

[breizh]

http://www.pressure-...ator/index.html

Consider this resource if you cannot get a copy of Crane TP 410 .

or


http://www.chemwork.org/sprd.html

Section download

hope this helps

Breizh

Edited by breizh, 26 May 2012 - 03:53 AM.

[katmar]

I have never seen pressure drop data for eccentric reducers. Not even Crane or Idelchik have it. Fortunately the pressure drop through reducers is usually a small part of the overall pressure drop and any inaccuracy here would not have a serious effect.

In my own work I have taken the resistance factor for eccentrics to be the same as a concentric of the same face-to-face length. I suspect that the symmetry of the concentric will give it a slightly lower resistance than an eccentric, so maybe you could add a 30% margin (only to the reducer) if you are in a critical situation. But mostly I think the range of uncertainty in all the other elements of the pipeline will swamp any slight inaccuracy in one reducer.