design of the mice rf cavity module :status of the module designmodule flange sealing options steve...

Design of the MICE RF Cavity

Module:• Status of the module design• Module flange sealing options

Steve VirostekLawrence Berkeley National Lab

MICE CM17 @ CERN February 23, 2007

Status & Installation of the Spectrometer Solenoids

Steve Virostek - - - Lawrence Berkeley National Laboratory

RFCC Module Design Status

•Prototype 201 MHz cavity is at FermiLab awaiting high power RF testing with applied magnetic field.




•Coupling coil design is under way at ICST in Harbin. Details of ICST/LBNL collaboration are being worked out.




•Two 42 cm curved Be windows have been fabricated by Brush Wellman. 3rd window is under way.




•Base mounting scheme for RFCC and other MICE modules has been established by RAL.




•Design and analysis of vacuum manifold system to be done soon. Issues: fields and space constraints.



Module Joint Sealing Issues

•MICE does not require metal seals on vacuum joints, but a future machine will

•MICE module joints may need somewhat frequent disassembly (maintenance, repair, reconfig.)

•O-rings will provide the most reliable and cost effective (inexpensive and re-useable) solution

•But, MICE should demonstrate all technologies for a future machine including the use of metal seals

•How is this achieved w/o undue burden on MICE?



Joint Sealing Options

RF ModuleAFC Module

Weld

~36 Bolts

Metal Wire Seal or O-ring

Commercial Bellows

Weld Lip



O-ring Pros and Cons

PROS

•Extremely reliable for vacuum sealing

•Inexpensive and re-useable seal

•Allows for quick open/close turnaround

CONS

•Cannot be used on a future machine

•Requires unscratched sealing surfaces



Metal Wire Pros and Cons

PROS

•Demonstrates seal for future machine

•Very reliable once sealed; moderate expense

•May allow for quick open/close turnaround

CONS

•Will require some level of R&D to perfect

•Requires smooth sealing surfaces & high loads

•Seal material is not re-useable



Weld Lip Pros and Cons

PROS

•Demonstrates seal for future machine

•Extremely reliable long term seal

•Allows for imperfections in mating surfaces

CONS

•Cannot carry loads across bellows with bolts

•Labor intensive for installation and removal

•Limited number of weld/grind cycles allowed



•Always use O-rings for all module joints

•Always use O-rings for all module joints but demonstrate one of the metal seals off line

•Use O-rings for all joints until final MICE assembly when only one metal seal is used

•Use O-rings for all joints until final MICE assembly when all metal seals are used

•Always use metal seals for all joints

What are the options in our approach?



•Must develop an approach to demonstrate vacuum sealing technology without future machine excessive burden on MICE

•Need a decision on the preferred approach

•A compromise between O-ring and metal seals is a likely choice

•Off line tests of metal seals recommended

•Metal wire is less complex than welded lip

Summary

design of the mice rf cavity module :status of the module designmodule flange sealing options steve...

Documents

status installation

spectrometer solenoidspage

mice module joints

mice rf cavity module

module designmodule

cons pros

future machine

mice modules