Update on Cleanroom, Clean water,

1

• Update on Cleanroom, Clean water,
• HPR systems and Field Emission
• J. Mammosser (Jlab)

2
Outline

• Quick Review of Cleanroom, DI water and HPR
  Details
• Discussion on DESY and JLAb facility operations (
  A. Matheisen, N. Krupka, L. Lilje, J. Mammosser)
• Field emission at Jlab, what is our approach to
  solving
• Discuss Jlab plans IP3I (C. Reece)
• Review of the DESY process steps with these
  facilities in mind
• Review WG5 RD recommendations (Cleanroom, DI
  water, HPR)
• Review current list relating to these facilities
  (L. Lilje)
• Identify details of each item in the list
• Review Care and DESY efforts

3
Cleanroom Facilities

• With current State of The Art processes
• All of the final cavity and subcomponent cleaning
  taking place in the cleanroom areas as standard
  procedure
• HPR system fully integrated into facilities
• All critical assemblies taking place in Class 10
  
• The cleanroom is one of the major critical
  facilities in the current process !!
• What is the current state of SRF facility
  monitoring, cleaning and maintenance?

4
Cleanroom Facilities

• Facility cleaning
• DESY ? Has external cleaning staff that starts at
  the end of the work shift as well as DESY staff
  that perform some cleaning steps when necessary
• Floors daily and walls once per week
• JLAb ? Has external cleaning staff that starts
  during the day and Jlab staff perform major
  facility cleaning after maintenance downs and
  when necessary
• Floors and trash daily
• Walls and filters every 6 months or prior and
  after string assembly

5
Cleanroom Facilities

• Maintenance
• DESY ?
• Once per year blowers , pre filters etc
• Jlab ?
• Once per year blowers , pre filters ect
• Require cleaning of blower housing and balancing
  of room pressures
• Twice per year opportunities for general
  maintenance during 1 week downs
• Require cleaning of full facility after facility
  shutdown

6
Cleanroom Protocols

• Staff Training
• DESY ?
• Training of staff On the job training with
  particle counters to qualify
• Outside training was performed in the past
• Plan to use return air particulate monitoring
• Jlab ? This needs much improvement!! (IP3I)
• Training of staff On the job from senior staff
• Outside training and videos used in the past

7
Cleanroom Protocols

• Entry
• DESY ?
• Allows up to 4 personnel in Class 100 at a time
• Allows 2 personnel in Class 10 at a time
• During module assembly 3 allowed , 2 working and
  1 backup
• Jlab ?
• No limit but typically 4 or less total unless
  cleaning than up to 6
• Class 10 area so small it only fit 2 working
• Personnel required to sign in logbook prior to
  entry and exit

8
Cleanroom Monitoring

• DESY ?
• Fixed locations for particle counting
• Fixed locations for QC steps
• Jlab ?
• Fixed locations for particle counting all major
  areas
• All areas still meet design standards (1990)
• No impact from number of personnel in facility on
  system performance
• Portable counters for process assembly steps
• Independent certification of all production
  cleanroom facilities 2002

9
What Changes Would You Make?

• DESY ? SRF 2005 Poster (K. Escherich et. al.)
• Cleanroom Facilities For High Gradient Resonator
  Preparation
• Supply and maintenance areas accessible from out
  side
• Filter fan units to reduce recovery time
• Independent air supply for chemistry safer
• Better product flow to reduce cross
  contamination, one way path
• Jlab ?
• Outside consultant identified many things , here
  is just a few!
• Improved cleaning of components prior to entry
• Separate area for nitrogen cleaning of sub
  components
• Reduction of amount and type of hardware entering
  facilities

10
DI Water System

• Monitoring
• DESY ?
• Online measurements of TOC and Resistivity
• Measuring points
• (Plant) between inline filter and UV lamp
• 7 POU locations routinely measured 2-3 days
• Bacteria checked every three weeks random POU
  locations
• Filter drain water for particle counts poor
  correlation with performance
• Jlab ?
• Online measurements of TOC, Resistivity and
  particle counts after final filter HPR
• Full analysis including Bacteria once per year,
  HPR and plant, next FY once per quarter smaller
  set monthly
• Particle counts poor correlation with performance

11
DI Water System

• Makeup Rate
• DESY 800-1200 l/hr
• Jlab 1000-1200l/hr
• Typically running most of the day, 2 HPRs , back
  flush at night
• Maintenance similar for both DESY/JLab
• Sanitize whole system once per year, replace
  filters polishers ect.
• DESY changes polishers every 2 weeks,
  resistivity low 17-17.5 ion exchange bottle
  rotation
• Jlab US Filter maintenance contract, ion
  exchange bottles on resistivity monitor , Virgin
  resin only
• DESY started preconditioning filters in
  separate loop to save flushing time

12
DI water Performance

• DESY Particle Counts 0.22um
• HPR POU Inlet
• 25 counts/l
• HPR Head (off)
• 22.8 counts/l
• Chemistry supply line
• 25 counts/l
• TOC Data
• 1.5-0.4 ppb

• Jlab Particle Counts 0.2um
• Plant final filter (HPR POU)
• 80 counts/l
• HPR Wand (on)
• 1600 counts/l
• TOC Data
• 40-1 ppb

13
Typical JLab HPR Data
14
HPR System

• HPR system is the single most important cleaning
  process to reduce field emission currently used
  and is the cavity final cleaning step
• After chemistry the cavity surface is in most
  contaminated state
• Flow through rinsing following chemistry is not
  enough to reduce field emission consistently

15
HPR System

• Specifications
• DESY ?
• Pressure -100 bar, LEWA Pump
• Flow rate ?
• 0.04um final filter
• Steam clean weekly to clean and kill bacteria
• New system design with a lot of changes
• Jlab ?
• Pressure 100 bar, LEWA Pump
• Flow rate 15 lpm, off 1-3 lpm
• 0.04um final filter
• Steam clean every 3 months

16
Jlab Water Analysis

• Typically Analysis (BALAZS Analytical Services)
• W0102 Bacteria-ASTM Method
• W0106 Total Oxidizable Carbon
• W0117 Dissolved Silica
• W0120 Total Silica
• W0121 Anions by IC
• W0123 Monovalent Divalent Cations by IC
• W0128 68 Trace Elements in Ultrapure Water

17
Jlab Water Quality
18
Jlabs new strategy to improving cavity
performance

• IP3I Strategy Just Starting (C. Reece)
• Codify procedures address everything we
  recognize as potentially affecting system
  performance
• Certified training to procedures developed, staff
  must demonstrate understanding and ability to
  follow them
• Culture of discipline for following procedures
  and highlighting difficulties
• Meaningful monitoring of process parameters

19
Jlabs new strategy to improving cavity
performance

• IP3I cont.
• Structured validation of procedures
• Validate effectiveness and merit of current
  procedures not supported by hard data
• Confirm procedure accomplishes what was intended
• Independent procedure improvement
• When procedure is not effective or unnecessarily
  burdensome, consideration of potential
  modifications is addressed by careful analysis
• New process development
• Development of new methods requires involvement
  of staff with mixture of theoretical
  understanding and practical experience
• Validating criteria established , meaningful
  experiments mounted and interpreted

20
Programs Identified at JLAb

• Procedure control improvements
• Documenting, training, qualification
• Integrate Nb witness samples into process steps
  BCP/EP
• Degreasing w/ detergent, Ultrasonic, Drying
• Chemistry and water rinsing (Fill and dumps, Hot
  DI)
• HPR, assembly HPR
• Assembly, evacuation, RF testing
• Field Emission Viewer
• Nb Samples for production processes identify
  start of field emission and record digital image
  of location
• Transfer to SEM for analysis if necessary

21
Field Emission Viewer
22
Cleaning Procedure Verification

• Idea
• Use ionized nitrogen cleaning method to identify
  and verify process cleaning steps if resolution
  is good?
• Concept
• Mounted ionized gun to end of cane with 30 ?
  deflection nozzle
• Simple linear actuator and rotary table (spare
  from HPR)
• Mount particle counter at cavity end for data
  collection
• Analysis method
• By comparison of total counts
• After various cleaning steps and drying
• After good and bad vertical tests

23
Ionized nitrogen cane
24
IP3I cont.

• HPR Effectiveness Study (P. Kneisel)
• Goal is to understand the effectiveness of the
  HPR as a cleaning tool and optimize its
  performance
• Understand the impact forces on cavity surfaces
• Best methods for wand movements
• Cleaning effectiveness
• Ect.

25
Field Emission

• I first reported that field emission was the
  dominant gradient limitation on CEBAF cavities at
  the SRF workshop in 1993
• At Jlab we have been fighting field emission ever
  since
• What do we know? (Mammosser)
• Many changes in procedures and facilities have
  occurred at Jlab since 1990
• At beginning no HPR ? DI water soak, US DI
  water, Solvent rinse
• 1 of CEBAF 5-cells performed at 20MV/m ,
  Epk/Eacc 2.54

26
FE at JLab

• What do we know? (Mammosser)
• During SNS HPR pump was routinely failing
• We replaced our HPR pump (LEWA) after SNS
  production and had some improvement and is now
  fallen back
• Multicell cavities have FE-onset much lower then
  single cells
• Our Production FE-onset is lower then DESY for
  most structures
• HG and LL structures have performed much better
  than other shapes
• Spread in performance is large

27
(No Transcript)
28
Recent Single Cell Data
29
(No Transcript)
30
(No Transcript)
31
WG5 Identified RD relating to these facilities

• WG5 efforts have produced a list of areas where
  RD is necessary for BCD and well as ACD
  developments
• What is now needed is to flush out this list in
  more detail in order to
• Capture details of the thinking behind why and
  what has to be solved
• This will allow for a broader audience to
  participate in solving problems and help in
  designing and understanding results from
  experiments
• Need to discuss what data exists and allow for
  future presentations to better understand the
  problem
• Write up the identified RD requirements in
  detailed and formatted way

32
DESY Process Steps
33
DESY Process Steps
34
WG5 Identified RD relating to these facilities

• Final cleaning BCD choice
• HP Rinsing, Dry Ice Cleaning
• RD necessary
• Additional / improved monitoring on HPR
• Particulates on input water - online
• Particulates on output water online
• TOC
• Need a reliable system (Specification? Oil
  Contamination?)
• Online (High pressure side JLAB, Low pressure
  side DESY)
• Active carbon filter (KEK)
• Degassing of oxygen against bacteria (KEK)
• Dissolved solids
• Full water analysis (JLAb 1x year)
• Resistivity (all)

35
WG5 Identified RD relating to these facilities

• Improved cleaning power
• Optimization nozzle material, geometry, size
  (Jlab)
• Optimize flow rates, impact angles (Jlab, INFN,
  Milano)
• Optimize pressure (Jlab)
• Investigate electrostatic charging
• Change on oxide structure, monitoring needed
• Optimize duration of rinse
• Quantify water quality needed
• Post HPR handling
• Drying procedures
• Laminar flow in cleanroom (DESY,KEK, JLAb)
• Vacuum (DESY, KEK,Jlab)
• Understanding of the best vacuum system needed
  (Jlab)
• Oil Free (DESY)
• No particulate contamination

36
WG5 Identified RD relating to these facilities

• Drying procedures cont.
• Hot nitrogen drying (Jlab) (with in-situ bake)
• Heating
• With evacuated cavity (KEK) In-situ bake
• Air Bake (SACLAY)
• Alcohol rinse
• Storage until test
• Air, vacuum, clean nitrogen, argon
• Assembly
• Standardization of cleaning methods for sub
  components
• CF. mass production
• QA of particle counts ect
• Main power coupler
• Can it be cleaned like the other components
  (before processing?)
• Documentation of assembly procedures

37
WG5 Identified RD relating to these facilities

• Assembly cont.
• QA of particle counts ect.
• Training of people
• ACD priority 1
• Dry ice cleaning
• RD necessary
• Need Proof of principle on horizontal cleaning
  process
• Multi-cell issues need to be solving

38
WG5 Identified RD relating to these facilities

• Furnace Treatment
• BCD RD necessary
• Attach Furnaces to cleanroom
• Frequency tuning
• Integration into cleanroom seems desirable ?

39
Care and DESY efforts

• CARE
• Systematic study on EP (SACLAY)
• sulfur production
• Bath aging
• Surface brilliance
• EP mix variations
• 1 Cell tests
• Automated EP (INFN)
• Dynamic control
• Fluxgate magnetometry

40
CARE and DESY efforts

• CARE
• Dry ice cleaning (DESY)
• DESY
• Understand HF outgassing from acid bath
• Quality control of acid (Henkel)
• IV curve and titration, NMR
• New HPR system design
• JLAB (IP3I)
• HPR studies
• Evaluation of cleaning methods