Re: Horizontal Dummy Leg Question

From: <harish>
Date: Fri Apr 16 2004 - 07:00:00 EDT

Dear,
I don't think by visualy seeing we can say the "I don't think the stresses generated are likely to be greater than those on a dummy leg welded to a 90 degree elbow"
Since stresses developed at a point in geometry not only depends upon the bending leg ( but more on the Stress Intensification Factor And Stress Concentration Factor) Since u'r bend is having 45 Deg turn its ovalization will govern its flexibility, Pressure stiffening ( rigidity ), and the Stress concentration due to change in geometry at the intersection point and lot more weld thickness and change in the homoginity of material due to welding , Residual stress.

• Gordon.Reddek@Alcan.com wrote:
  > Paul,
  >
  > I can not recall seeing that particular detail
  > however it would not worry
  > me to use it. I don't think the stresses generated
  > are likely to be
  > greater than those on a dummy leg welded to a 90
  > degree elbow. I expect
  > you are concerned about the stresses generated at
  > the joint between the
  > elbow and the leg. The bending moment is spread over
  > a much larger area at
  > the contract point in this case compared to the 90
  > degree elbow case so I
  > would expect the stresses to be less.
  >
  > Gordon Reddek
  >
  >
  >
  >
  >
  > "Paul Bowers" <pbowers@pipingdesign.com>
  > 16/04/2004 09:50 AM
  > Please respond to PipingDesign
  >
  >
  > To: <PipingDesign@yahoogroups.com>
  > cc:
  > Subject: [PipingDesign] Horizontal
  > Dummy Leg Question
  >
  >
  > Has anyone ever seen a horizontal dummy leg used on
  > a 45 degree elbow?
  >
  > Here's a quick sketch:
  >
  > <a href="http://www.pipingdesign.com/drawings/dummy.jpg">http://www.pipingdesign.com/drawings/dummy.jpg</a>
  >
  > It is assumed that the non-penetrating weld between
  > the DL and the elbow
  > would overlap, although the sketch doesn't show
  > this.
  >
  > Paul
  >
  >
  >
  >
  >
  > =========================================
  > PipingOffice - Excel Spreadsheets for Piping
  > Calculations
  > <a href="http://www.pipingoffice.us/">http://www.pipingoffice.us/</a>
  > =========================================
  > Main site: <a href="http://www.pipingdesign.com">http://www.pipingdesign.com</a>
  >
  > Yahoo! Groups Links
  >
  >
  >
  >
  >
  >
  >
  >
  >
  > [Non-text portions of this message have been
  > removed]
  >
  >
  

  ---

Do you Yahoo!?
Yahoo! Tax Center - File online by April 15th <a href="http://taxes.yahoo.com/filing.html">http://taxes.yahoo.com/filing.html</a> Received on Fri Apr 16 07:00:00 2004