MICE RFCC Module 201 MHz RF Cavity Fabrication Update
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Progress Summary
Cavity fabrication awarded to Applied Fusion in Feb. 2009Cavity
body fabrication started in April 2009Welding the stiffener ring to
the shell and cutting the iris is completeCopper shells with the
stiffener ring have been e-beam welded into 5 cavitiesPorts have
been extruded into the perimeter of all cavitiesWelding the nose
ring into the cavity irises is completeWelding the strut mounting
posts onto the cavity is completeWelding of the cooling tubing onto
the cavity is on goingThe first 5 cavities are scheduled to be
delivered by end of CY2009
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Strut Mounting PostCooling TubingCavity Component PartsStiffener
RingNose RingCavity ShellsExtruded Port Flange
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity Fabricator - Applied Fusion, Inc.
Applied Fusion, Inc.1915 Republic Ave.San Leandro, CA 94577
Applied Fusions e-beam welder is a German made machine
Applied Fusion has the machining equipment necessary to
fabricate the complete RF cavity (minus spinning)Electron beam
welding machine
Milling Machines
Inspection
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Title HereThe stiffener ring is welded on to the half shellThe
iris is machined outCavity Stiffener Ring
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
The cavity shells were inspected at LBNL and paired for best
inside edge matchMatched shells were e-beam welded into a cavityThe
cavity shells are oriented (clocked) to the stiffener rings with a
pin
E-beam Weld Shells into a Cavity
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity is placed on a horizontal milling machine to bore the
pilot hole for the extruded portsThe shell alignment key is bored
out as one of these pilot holesBore Hole for Extruded Port
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Ports are extruded using LBNL provided tool
The inside of the perimeter weld is ground to blend the two
shell halvesPort flange is e-beam welded to a machined port
faceExtruded Port
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
The nose ring is welded into the iris of the cavityThe inside
weld is ground down to blend the nose ring into the cavity
wallThreaded holes for mounting the Be window to the cavityNose
Ring Welded into Cavity Iris
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
The cavities will be suspended inside the vacuum vessel with 6
struts in a hexapod arrangementStrut Mounting PostStrut mounting
posts will have a Heli-coil thread insert for strengthStrut
mounting posts are TIG welded to the cavity
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cooling TubingCavity cooling circuit uses one continuous tubeNo
in vacuum cooling tube jointsTubing is TIG brazed to the cavity
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity Cooling Tubing FinishedCavity cooling circuit completely
TIG brazed onto cavity Tubing is fully leak checked
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity Beryllium Windows Cavity Be windows are being fabricated
by Brush Wellcome LBNL has received several finished windows
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity Be Window Inside look at the Be windowCavity Be window
alignment to nose ring looks goodSome machining of the nose ring
may be necessary to flatten mounting surface
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity Progress Summary
Most fabrication operations for the first 5 cavities (four plus
one spare) are completeCooling tube welding is on goingCavities are
due to be delivered to LBNL by the end of the year
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Future Work
Cavities must be tuned to each other for best center frequency
(four cavities) by plastic deformation (will be done at LBNL)The
inside surface of each cavity needs to be electro-polished (done at
LBNL)Frequency tuner system testing and verification will be done
on a finished cavityExercise option to order the remaining 5
cavities (four plus one spare) for the second RFCC module
MICE RFCC ModuleCavity Frequency TunerDesign Update
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Progress Summary
Tuner design is complete scale model has been fabricated to test
conceptOne full size tuner arm (for testing the system) is in
fabricationThree RFQs for the bellows style actuator have been
issuedControl system components have been identified
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity Frequency Tuners24 Dynamic Cavity Frequency Tuners per
ModuleTuner ActuatorTuners operate in a bi-directional push - pull
mode (2mm)Tuning automatically achieved through a frequency
feedback loop
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Designed around a flexure concept Stress levels seen in the FEA
model are within material limits A bi-directional tuner and
actuator design reduces bellows diameter and/or pressure
requirements.Two Emerson ER3000 electronic pressure controllers
[regulators] per cavity (one for each side of actuator piston) will
control the 6 actuatorsUse of a high pressure regulator between N2
tank and supply lines to reduce supply pressure to 120 psi
Cavity Frequency Tuner Design Overview
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Cavity Frequency Tuner ComponentsDual bellowsvacuum sealingDual
action tuner actuatorFlexure tuner armScrews fix the tuner to the
cavity stiffener ring (both sides)Actuator is screwed intothe tuner
armFixedconnectionForces are transmitted to the stiffener ring by
means of push-pull loads applied to the tuner lever arms by the
dual action actuator assemblyTuner/actuators are thermally
independent of the vacuum vessel
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Actuator DesignActuator design incorporates a sealed enclosure
between vacuum and air.Actuator is mounted to the tuner arm
onlyBellows allows angular movement for actuatorPiston plates are
joined at the perimeterPiston plates incorporate hard stops
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
MICE RF Cavity Mechanical Design and AnalysisActuator inlet and
outlet penetrate the rigid enclosure
Actuator design incorporates push and pull actuation through
holes in the center plateActuator Design Details
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
FEA model with tuning arm and a test ring
Tuning arm made from 3.0 stainless steel plate
Cylindrical test ring replicates 1/6 of cavityTuner System
Analysis Model
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Tuner System Test Ring AnalysisFEA of one tuner on 1/6 test ring
cavity segment Test ring: 440 lbs applied force 1/6th of measured
cavity spring rate value (2600lbs @ 2mm)1.04mm displacement per
side (Ring ID=14.3)
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Tuner System AnalysisAt the actuator the tuner arm displacement
is 0.214 (~0.43 bi-directional)The cavity displacement is 1.05mm
per sideThe maximum Von Mises stress at the flexure is 29.7Kpsi
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Tuner System AnalysisThe Von Mises stress at the flexure is
29.7KpsiThe input load by the air actuator is 800 lbsThe tuner arm
displacement is 0.214 (~0.43 bi-directional) [movement exaggerated]
The cavity displacement is 1.05mm per side
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Bi-directional actuator design requires two electronic pressure
controllers [regulators] (one for each side of actuator piston)
2. Regulators and pressure supply:a. Use high pressure regulator
between N2 tank and supply lines to reduce supply pressure to 120
psib. Actuator pressure controller:i. Emerson ER3000 electronic
pressure controllersc. Use burst disc or safety valve in supply
lined. A constant leak or valved-leak is required in actuator
manifold to allow for relaxation of the tuner (design on
going)Pressure System Requirements
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Emerson ER3000 electronic pressure controller 0.1% accuracy
(over 110 psi range)110 psi normal operating range (120 Max.)Remote
computer controlled16 required for two RFCC modules ($1,292.00
ea.)
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Designed around a flexure concept Stress levels seen in the FEA
model are within material limits A bi-directional tuner and
actuator design reduces bellows diameter and/or pressure
requirements.Two Emerson ER3000 electronic pressure controllers
[regulators] per cavity (one for each side of actuator piston) will
control the 6 actuatorsUse of a high pressure regulator between N2
tank and supply lines to reduce supply pressure to 120 psiCavity
Frequency Tuner Design Summary
MICE RFCC Module Update MICE CM25 at RAL, UKPage *Allan DeMello-
Lawrence Berkeley National Lab November 6, 2009
Schedule Summary
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