Elbow Schedule
Elbow Schedule
(OP)
We need to replace a 6 NPS Sch 120 elbow in piping system. In our store we have a 6 NPS Sch 160 elbow. Can we use this new elbow with a higher sch.
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS Come Join Us!Are you an
Engineering professional? Join Eng-Tips Forums!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Posting GuidelinesJobs |
|
RE: Elbow Schedule
Is it of the same material as the old elbow ?
Make sure that you taper the inside of the elbow near the two welds ( I assume that it is butt welded).
ASME B31.1 states that it should be a minimum of 3:1 taper
RE: Elbow Schedule
rmw
RE: Elbow Schedule
The material is same ASTM A-234 WPB. However, as you know both will have different ID at root face. Would it hurts.
RE: Elbow Schedule
If you left it alone and just tried to make the weld with the dissimilar ID's, not only is it poor practice and most likely a code violation, but you also wouldn't meet the high-low/maximum permissible ID mismatch weld fit-up requirements of most ASME codes.
RE: Elbow Schedule
1. The thicker ell decreases the flexibility of the piping system which could potentially result in higher stresses and/or higher loads on branches and equipment nozzles.
2. The smaller ID of the ell will increase pressure drop through the system.
In probably most instances neither concern may result in a problem, however, if you are not confident in evaluating these issues yourself then involve someone who can. This would be my recommendation.