7/8/08 John Amann LC Mechanical Engineering LC 18M W Beam Dump Mechanical Engineering Design Updates

7/8/08 John Amann LC Mechanical Engineering Topics Mechanical design of dump window and weld flange. –Duplicated Dieter’s analytical calculations for static stress with FEA model of hemispherical window. –Created alternate design, ellipsoidal window and FEA model of static stress for comparison. –Design studies for weld flange. Design of upstream mechanical systems (vacuum to dump transition). –Many design drivers to address. –Meetings with Ray and Dieter, converging on preliminary design concept.

7/8/08 John Amann LC Mechanical Engineering 30cm Hemispherical Window FEA Model Static Mechanical Stress Maximum Static Stress psi internal pressure) Dieter’s analytical calculation: 11,130 psi ANSYS FEA Model: 11,183 psi Maximum Z displacement =.003” Advantage of FEA model is we are able to see the stress distribution. Alloy: Ti-6Al-4V, 1mm thick E=13.1 x F

7/8/08 John Amann LC Mechanical Engineering 30cm 2:1 Ellipsoidal Window FEA Model Static Mechanical Stress Maximum Static Stress psi internal pressure) ANSYS FEA Model: 27,459 psi Maximum Z displacement =.031” Compared to hemispherical window, ellipsoid window has significant bending stress. Alloy: Ti-6Al-4V, 1mm thick E = 13.1 x F

7/8/08 John Amann LC Mechanical Engineering Von Mises Stress Comparison Von Mises stress criteria is useful to evaluate yielding in metals. We want the von Mises stress to be less than the yield stress. For Ti-6Al-4V the yield stress = x F. The hemispherical window has lower von Mises stress than the 2:1 ellipsoidal window.

7/8/08 John Amann LC Mechanical Engineering Dump Window Weld Flange Design Goal: Design a dump window weld flange under guidelines of ASME BPVC and compatible with titanium alloy fabrication methods. Challenge: Welding thin window (1mm) to thicker (~5cm) material. For remote dump window interchange, a thick dump window frame is required. One solution is an intermediate weld flange. Weld Prep for E-Beam Fusion Welding Weld Flange Thin Window

7/8/08 John Amann LC Mechanical Engineering Design Drivers - Upstream Systems Need to isolate dump window from machine vacuum. –Air gap (air activation)? –Continuous piping with He gas buffer (incomplete isolation if both windows fail)? Thin Vacuum Window –Likely to need some sort of direct cooling either He or H 2 0, peripheral cooling probably not sufficient. (Dieter is finishing calculations for window cooling.) –Want to isolate vacuum from rad water, excludes H 2 0 cooling. –Remote replacement needed, will become highly activated. –Prototypes to study weld flange design, gasket design, corrosion, erosion and beam damage testing. Need to start soon if $$ available.

7/8/08 John Amann LC Mechanical Engineering Vacuum Window Cooling Module Machine Vacuum Thin Windows He Gas Inlets/Outlets for Window Cooling Need to design solutions for: Remote window interchange with UHV. He gas supply and return connections. He leak tightness, minimize He entering machine vacuum or loss to atmosphere. 316L SS CF Flanges and Beam Pipe, Cu Gaskets.