Hi Lumi WP 4 Crab Cavities Calculations Update

Hi. Lumi WP 4 – Crab Cavities Calculations Update from CERN logo area 22. 07. 2016

Vacuum vessel: BCs and loads • Vacuum vessel was checked for the operational conditions. Pressure 0. 1 MPa Fixed support FPC reaction force 2500 N Rod reaction force 900 N Gravity 9806. 6 mm/s 2 900 N 2500 N 900 N • Bolts were not modelled due to validity of a bonded model. • Welds were modelled between the particular components as bonded edge-to-face contacts. Material for windows: • Al AW 6082 Total mass: 2675 kg logo area CERN 2

Deformation of vessel Lateral deformation • The lateral deformation of the vessel is 0. 84 mm. • The max vertical deformation is 0. 25 mm and occurs on the FPC plate due to bending. logo area Top plate deformation CERN 3

Vertical deformation of top plate • The real deformation of the vessel is around 0. 11 ÷ 0. 16 mm. Deformation of the FPC plate: 0. 23 ÷ 0. 25 mm Deformation of the top plate: 0. 11 ÷ 0. 16 mm logo area CERN 4

Leak tests: partial Top Lunette logo area Bottom Lunette - Frictional contact between plates and cavity - Vacuum in enclosed space CERN 5

Leak tests: partial Top Lunette Bottom Lunette - Frictional contact between plates and cavity - Vacuum in enclosed space Partial leak test should be performed on the top lunette (the one with FPC). Local stress is high on the other one logo area CERN 6

Leak test total Local high stress may determine small plastic deformations with subsequent frequency drift logo area CERN 7

Thank you for your attention! logo area CERN 8