From: Mark Smith

Sent: Monday, July 25, 2011 12:55 PM

To: Peter Titus; Ali Zolfaghari

Cc: Lawrence E. Dudek; Bob Simmons

Subject: pedestal calc

Hi Pete.

I have a few questions for the pedestal calculation.

(1) What figure has the results for the simultaneously applied loads?

Also, in the executive summary (calc page 6), no stress concentration factors are used for the welds.

This seems generous. Typically, you have used a factor of 4.

(2) Is no stress factor within AWS standards for full penetration welds?

Note, scenario 79 has been used for the worst applied torque.

Based on the design point sheet, there is about a factor of 1.5 between sc 79 and sc 21 torque.

Assuming linear behavior, sc 79 would scale to about 202 MPa.

A modest weld stress factor (1.48 vs 4) puts the pedestal above the 300 MPa weld allowable.

Mark Smith

Mechanical Engineer

Princeton Plasma Physics Laboratory

P.O. Box 451

Princeton, NJ 08543-0451

(609) 243-2778