NSTX Supported by NSTX Centerstack Upgrade Project Meeting P. Titus Feb 3, 2010 Dome Rib Tab Weld Stress Removing TF OOP Support to the Vessel

Design Point PF Forces Fz(lbf)PF1cUPF2UPF3UPF3LPF2LPF1cL Min Worst Case Min Max Worst Case Max

/title,PF4 and PF5 Upper Worst Power Supply Loads Plus TF OOP Loads bf,all,temp,20 f,985,fz, /12/.2248 !PF1c f,402,fz, /11/.2248 !PF2 f,4588,fz, !Umb Foot f,4588,fy,60000 f,1237,fz, /11/.2248 !PF3 solve

Reference and WeldRod or weld wireParent MaterialAllowable Stress (Exclusive of Weld Efficiency) AISC Stress on cross section of full penetration Welds AllSame as Base material AISC Shear Stress on Effective Throat of fillet weld AWS A5.1 E60XXA ksi Weld Allowable For shear on an effective throat of a fillet, For 304 Stainless, the weld metal is annealed, or the base metal in the heat effected zone is annealed. and Estimate 241*21/36 = 140 MPa = 20 ksi (without weld efficiency) This is consistent with NSTX Criteria of 2/3 yield or 2/3 of 30ksi for annealed 304 With a weld efficiency of.7 the allowable is 14ksi, or 96 MPa For fillets divide weld area by sqrt(2) For welds in steel, the design Tresca stress shall be the lesser of: 2/3 of the minimum specified yield if the weld at temperature, or 1/3 of the minimum specified tensile strength of the weld at temperature. From the NSTX Criteria: From the AISC Criteria:

Rib Tab Weld Evaluation for Worst Case Power Supply Loads Actual Weld Detail Assume bevel backed by a fillet is like a full penetration. Tab weld Stresses all appear less than 96 MPa

Sri Checked Vessel Stresses with Correct NB Port, and Han’s Worst OOP Loads – Vessel Stress is OK.

TF Stress, - No Outer Leg OOP Support Note Scenarios beyond around #50 died due to filled disk

OOP Displacement, - No Outer Leg OOP Support