1 / 7

Vacuum Vessel Structural Analysis

This analysis examines the structural integrity of a vacuum vessel and closure heads, including the vessel shell, ribs, flanges, and aluminum weldment. The analysis considers stress and buckling criteria, loading conditions, and results for both the shell and closure heads.

joshual
Download Presentation

Vacuum Vessel Structural Analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Vacuum Vessel Structural Analysis SS Shell Weldment Aluminum Closure Heads(With Silicon Bronze Bolting)

  2. Cold Mass & Vacuum Vessel Assembly • Vessel shell, ribs & flanges - welded SS • Cold Mass suspended from top of vacuum vessel • supported by 4 tension rods • Constrained by lower alignment pin • Rotating fixture allows assembly rotation • Cold mass connected to vessel flanges by tooling • Included for shipping of hardware

  3. Vessel Closure Head Assemblies • Aluminum 6061-T651 construction • 1.5 inch thick plate for membrane • 3 inch thick plate for reinforcment ribs • Includes openings for beam tube & particles • Reinforcement ribs to be bolted to membrane • Silicon Bronze bolts (eight 1-10 UNC) • Ribs perforated to accommodate bolt installation • Blind bolt holes in membrane for vacuum tightness

  4. Criteria • Membrane Stress Allowable (=Sm) • Stainless Steel - 16.7 ksi (115 MPa) • Un-welded 6061-T651 Alum - 13.97 ksi (96 MPa) • Welded 6061-T651 Alum - 7.9 ksi (55 MPa) • Membrane + Bending Stress Allowable (=1.5Sm) • Stainless Steel - 25 ksi (172 MPa) • Un-welded 6061-T651 Alum - 21 ksi (144 MPa) • Welded 6061-T651 Alum - 11.85 ksi (82 MPa) • Silicon-Bronze Bolting - 11.3 ksi (78 MPa) • Buckling - Safety Factor = 2 (4 if BC’s not precise)

  5. Loading Conditions • Without the closure heads: • Deadweight (w/ cold mass on stand with lateral accel.) • Deadweight (w/ cold mass on rotating assembly fixture) • Deadweight (vessel only on rotating fixture) • With the closure heads: • Deadweight (w/ cold mass with press/vacuum +accel.)

  6. Shell Analysis Results • Shell Internal pressure (30 psia max) • Min wall = 0.136 inch < actual wall 0.375 inch • Shell external pressure (buckling) • Code-based calculations with FS of 4:1 • Max. external pressure calculated = 14.8 psi • Vessel & cold mass, w/o heads, on stand • Max stress in shell = 82.4 MPa < Membrane allowable • Max deflection of flange < flange bolt clearance • Vessel & cold mass, w/o heads, on fixture • Stresses negligible (< 1ksi)

  7. Closure Head Analysis Results • Finite element Results • 15 psi external loading on 1/8th symmetry model • 11.8 ksi calculated < 14 ksi allowable for un-welded 6061 • At weld between rib & central tube: • 4.3 ksi membrane stress < 7.9 ksi allowed for welded 6061 • 9.8 ksi mem+bending stress < 11.85 ksi allowed for welded 6061 • 11.8 ksi peak stress < 24 ksi allowed for welded 6061 • Max. bolt stress 9.66 ksi < 11.3 ksi allowable • Head buckling FS calculated to be 30:1 > 2 to 4 required • Max deflection about 0.1 inch (criteria undefined)

More Related