Aug 6, 1991 - Blue Sheet

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Project Progress Summary

August 6, 1991

Congressional budget action: The Senate has added $10 M in construction funds and $2 M in experimental equipment funds to the Energy and Water Appropriations Bill that includes CEBAF’s FY 1992 budget.

FET Operations

  • One day of operation with beam was used to measure the cavity and coupler kicks and the cavity field probe calibrations for six cavities of the Phoenix cryomodule.
  • Another day was used for further studies of arc trips on the RF windows.
  • The 100-MHz gun modulator was reworked to provide greater drive for the 100-MHz BPM system.
  • Operations of the “harp” beam profile monitor with pulsed beam was accomplished.
  • Installation of the fixed 180-degree bend system for the beam recirculation experiment was started.

WBS 1

Facilities:

  • Two new chem hoods commissioned.
  • The four-station, variable-speed lapping machine was received.
  • Twelve stainless steel keepers for conflat copper gaskets were etched for FET staff.
  • Interface to CTF established for pair testing pressure control valves. Use of this interface may increase efficiency.

Nb Pair Parts:

  • Pressed 12 sets of elbows; leak checked 13 elbows, one beam tube.
  • Machined flange weld prep on 18 elbows, seam weld for 12 elbows.

RF Windows:

  • The windows procedure development is going well.
  • Vendors have been contacted for off-site brazing. Samples should be available in three weeks.
  • The reverse pressure test windows have been thermal cycled and are being leak checked. At least three of the windows are leak tight. Window charging or puncture being investigated as a possible cause of the through leaks.

HOM Loads:

  • Assembled the same cavity pair used for the heated load test with four new glassy carbon loads. Damping at lower frequency appears adequate with both cavities’ modes damped to the same level. This indicates uniformity of performance of the loads. No temperature desorption was observed. This pair will be reassembled and reprocessed to determine the effect if the loads but not elbows are interchanged.
  • RF performance was checked for loads removed from the CE001/CE002 pair that was assembled last year and that had poor performance in the 1976-78 MHz band. They have about 1 dB loss at 2.1 GHz at 2 K. The Qext was 8.4 x 10^4 in CE002 at 1976 MHz. The performance of CE001/CE002 and that of IA101/IA089 provide two solid points for interpolation and possible extrapolation of the Qext vs. return losses of the loads at the 1970-MHz band.
  • Received aluminum nitride with titanium carbide tiles with 15-micron grain size (vs. 1-3 size). The dielectric constant properties seem better. Low-temperature tests show no temperature dependence.
  • Three tiles of glassy carbon material with 20-50 microns (vs. 3-12 standard) are undergoing preliminary tests. The dielectric constant loss tangent indicates usability.
  • Five new 8” x 8” glassy carbon tiles are unusable due to laminations induced by excessive temperature in the vendor furnace. The vendor estimates delivery of a new batch by the end of this week.

Cavity/Cavity Pairs:

  • IA089/IA101 was assembled last Thursday with the glassy carbon loads. It is being cooled down.

Cryounit/Cryomodules:

  • Two cryounits are complete in the cryounit area, and they will be transferred to the cryomodule assembly area for cryomodule traveler 8. One of these units has had the warm window modified to reduce the permeation through the teflon window. A layer Remaining tests will show how well it stands up with RF power.
  • The quarter-cryomodule is installed in the test cave. All U-tubes have been installed. Shield cooldown has begun and 2-K cooldown and fill were scheduled to begin today. The unit will be initially tested with RF power to establish a baseline and to assess Q’s and gradients, with thermal cycle tests to follow.
  • Last Thursday, the first cavity on Victory was tested to assess arcing. Arcs were recorded but required running the cavity in excess of 7 MV/m, not the 5 MV/m experienced earlier. An automatic measuring system is being installed to collect data.
  • A meeting was held to discuss the cavity vacuum checking procedure. A tentative plan was laid out that needs to be supported by travelers. The responsibility for connection of the FPC extension was transferred to the cryounit group.
  • The reworked parts for the cavity vertical attachment were completed by the machine shop and turned over to the cavity pair group. Additionally, the alignment/installation fixture cavity iris holder parts were modified. Checkout of these fixtures still remains to be done.

WBS 2

Installation:

  • The first quadrupole girder of the north linac was installed.

Magnets:

  • All 17 wide-pole, two-meter dipoles (BRs) and 19 of the 96 standard two-meter dipoles (BBs) have been received from Process Equipment Corp.
  • The proposals for the QB quadrupoles went to the “best and final offer” stage.

Magnet Measurement:

  • The 48 one-meter dipoles have been measured and assigned to positions in the first and third beamlines in the east arc. The uniformity of the dipoles in the first line over the operating range is one-half specification, and the uniformity of the third line is better than specification by an order of magnitude.

Stands:

  • The pedestals for the south linac were received.

Vacuum:

  • The bending of the 226 dipole tubes to the appropriate arc shape started at the bending vendor.
  • An area with appropriate tooling is being set up in the test lab so that centerlines of the quadrupole beam pipes and the centerlines of the beam position monitors can be made coincident by forming operation after they are assembled here at CEBAF.

System Integration:

  • The song sheets (Top Accelerator Assembly Drawing) for elements in the first extraction area and last two-thirds of the east arc were signed at the WBS 2 level and sent to Project Management for further approval by other work breakdown structure representatives.

WBS 3

Controls:

  • The problem with “save settings” was traced to a faulty algorithm in the microprocessor embedded code that was resetting the offset register without a TACL command. Now RF settings return within one degree of previous measured values.

RF Power:

  • The final order for 64 HOM filters was placed with Gamma Microwave. Delivery will begin in March.

Fabrication:

  • Received large lot of fabricated cables from each of our cable vendors. The quality is much improved as a result of our several visits to their shops.
  • Sent two sets of control racks to the north linac for installation (zones 10 & 11).
  • Completed and shipped 33 sets of waveguide assemblies.

WBS 4

  • Continuing assembly and testing of trim systems and associated components. A total of 16 trim systems have been installed to date.
  • Recirculator cable tray installation was begun.
  • Telephone cables have been pulled through the north lianc and east arc service buildings and tunnel.
  • As-build drawings for the injector service building AC power are being assembled.

WBS 5

  • BPM test stand work has restarted. Completion is anticipated next week.
  • RF kicker for recirculation experiment is moving to the vacuum tight version.

WBS 6

  • No report received.

WBS 7

  • The 2-K repair in the north linac has been completed.
  • All the warm piping in the south linac has been leak checked.
  • In the southwest quadrant, the first section of return transfer line has been installed and leak checked.
  • In the northeast quadrant, the 8-inch pipe in the return transfer line is being vacuum pumped for leak checking.
  • One section of return and supply transfer line along with the south linac return tee were shipped to the tunnel this week.
  • An operational computer simulation of the 2-K cold box has been completed. CVI has been informed, and it was requested that LAL witness the simulator prior to returning to France. CVI is scheduled for 19 August. Cooldown is scheduled for 16 September. The CHL acceptance test will be started at this time.

WBS 8

  • Continued working on third-lift Hall B wall sections. Completed the beam dump connector and the beamline tunnels for Hall B.
  • Completed installing shoring in Hall C, and now installing the ribs and decking to support placement of the concrete dome.
  • Backfilling continues in all areas when weather permits.
  • Foley Crane is mobilizing in preparation to start installing the crane in Hal A this week.
  • MCI, the end stations above-ground subcontractor, has completed construction of about one-third of the footings for the ESR (end station refrigeration) building.

Support Services

Machine Shop:

  • Front End Test fabrication for 85-MeV recirculation experiment in process:
    • Ten precision magnet mounts.
    • Six pedestal assemblies for Illinois magnets.
    • First and second doublet magnet stands.
    • Four QB magnets for the doublet region.
    • Began fabrication of a prototype “transition recirculatory kicker” for WBS 5.

Stockroom:

  • Activity for the week: $23,915.75.
  • Activity for the month: $74,003.48.
  • Delivered 345 RF and IF boards to WBS 3.
  • Ultra-jet cleaning system and cartridges will no longer be available in the stockroom. A carbon dioxide duster system will be substituted due to safety and environmental concerns.

External Fabrication:

  • Received six recirculatory return line “pedestal stands” for the Front End Test.
  • Received and delivered “tri-pole magnets” for WBS 2.
  • Produced drawings for the construction of front panels required for technical stockroom.

CEBAF Summer Science Series Wrap-Up

Hermann Grunder will discuss accelerators and the future in the final seminar of the Summer Science Series this Friday, 9 August, at 3:30 in the auditorium.

 

Quality Assurance and Safety Poster Contact:

Winners are:

First Place                          Karelyn Lloyd

Second Place                     Lori Powell

Third Place                         Jeff Hartline

 

Honorable Mention:

Sylvia Corneliussen                         Robert Holt

Patty Hunt                                         Danielle Hunt

Jamie Hunt                                        Jason Kozma

 

The posters will be on display throughout August in CEBAF Center on the second floor of the atrium. In September, the posters will be displayed throughout CEBAF work areas. Thanks and congratulations to all participants – prizes are being mailed.

 

Training Opportunities

A new Training Opportunities Bulletin has been distributed. The bulletin details and described courses on Employee Orientation, Sole-Source Procurement, Macintosh Computers, and Basic X Windows Programming, as well as the following listings:

Radiation Worker Training – 12 August (repeated 16 September) 8:30-11:30 Auditorium

Cardiopulmonary Resuscitation (CPR) Training – 20 September – 1:00-5:00 Rooms 53/55

Incidental Crane Operator Training – 22 August (repeated 26 September) 8:30-5:00 SRF Conference Room (test lab 2nd floor)

Forklift Certification Training – 20 August (repeated 24 September) 8:30-5:00 SRF Conference Room (test lab 2nd floor)

Also offered will be the four separate classes of the morning0long CEBAF Safety Orientation, held 14 August (and repeated 11 September) from 8:30 to noon in the auditorium. The four classes are: Radiation Protection Orientation, 8:30-9:25; Emergency Management and Hazard Communication Training, 9:30-10:25; Oxygen Deficiency Hazard (ODH) Training, 10:30-11:10; and Lock and Tag Procedures, 11:15-noon.