# Presentation: 814685

##  Status of Magnet R&DNov. 7th 2002James T VolkFermilab

- NLC - The Next Linear Collider Project

-  Status of Magnet R&DNov. 7th 2002James T VolkFermilab

***James T Volk***
*** ***

- 11/07/2002

## People Involved

- Joe DiMarco, Vladimir Kashikin, James T Volk
- Fermilab
- Scott Anderson, Seung Rhee, Cherrill Spencer, James Spencer, Zack Wolf
- SLAC
- Steve Gottschalk
- STI Optronics
- Bellevue Washington

***James T Volk***
*** ***

- 11/07/2002

## Electro Quad on SLAC test stand

***James T Volk***
*** ***

- 11/07/2002

## Y coordinate of the electromagnetic quad’s magnetic center measured over 2.5 days

- Current changed in a BBA sequence:black circles are Y center at 80 amps, open circles are Y at 5 different currents which quad would be run at for a BBA: 64, 67.2, 70.4, 73.6, 76.8 amps

- Variation in Y during any one BBA sequence  to be < 1 micron is satisfied.

- Run 31, 25th –28th  October  2002

## Wedge Quad

***  ******James T Volk***

- Pole magnets

- Wedge magnet

- Tuning rods

- 11/07/2002

## SLAC Rotating Coil Data

- 11/07/02

***James T Volk***

## Rotational Quadrupole with Correction Coil System

**Rotational quadrupole assembly**

**Stepping motor**

**Rotational quadrupole assembly (side view)**

**Correction coils**

***V.S.Kashikhin***

**Rotational Quadrupole with Correction Coil System**

- 11/07/2002

## Correction coils

**Rotational quadrupole control system**

**First analog active correction system test... in progress**

**Without   correction**

**With active correction**

***V.S.Kashikhin***

## Rotational Quadrupole with Correction Coil System

**1 ********m center shift = 1 G dipole field  = 1 A correction coil current**

**Integrated signal from measuring coil during magnets rotation**

**Amplifier -  ****Integrator**

**Power Supply**

**Measuring coil**

**Correction coil**

**            ****Active Correction System**

***V.S.Kashikhin***

**Center shift vs. correction coil current**

- 11/07/2002

## Counter Rotating quad

**1 um center stability with correction coil**

- 11/07/2002

***V.S.Kashikhin***

- microns

## STI Phase I PM Quad Prototype Results

- Work Supported by Department of Energy Grant DE-FG03-01ER83305

- AN SBIR grant to Steve Gottschalk
- Of STI Optronics of Bellevue Washington

- An adjustable quad where the magnet material moves

***James T Volk***
*** ***

- 11/07/2002

## STI Phase I prototype on SLAC bench

- All tests done by moving two magnets out of four

***James T Volk***

- 11/07/2002

**Notes:**
The PM quad was tested at STI with a Hall probe and at SLAC with a spinning coil. This viewgraph shows the unit on the SLAC spinning coil bench during testing.

##  Results on Phase I prototype

-  Strength is linear with brick retraction
- Sextupole is acceptable and doesn’t change during retraction of 2 bricks

***James T Volk***
*** ***

- 11/07/2002

**Notes:**
The shows linear strength vs. brick retraction on the left. With a 15mm retraction the field is reduced to 78% which meets the NLC requirement. The sexupole is essentially unchanged during retraction and meets the NLC requirements. EM quads have the same level of sextupole. 

## Centerline adjustment results

- Mechanical advantage 10X
- Linear shift with brick retraction
- Short term centerline repeatability is 0.4 microns
- Fine tune of brick shift with strength can make X CL zero at all retractions

***James T Volk***
*** ***

- 11/07/2002

**Notes:**
The right graph summarize short term x magnetic centerline repeatability tests. There were 6 repeats made over one day. Tuning range was 20%. The left graph shows that for any retraction a fine adjustment of the brick shifts will keep the centerline from changing during retraction. These results are consistent with STI Hall probe data.

## Long term X centerline results*

- Initial increase of X CL by 6 microns with spinning coil due to magnet supports
- Hall probe doesn’t show the same effect
- Improve supports for magnet and granite block

**Hall probe x CL**

**Spinning coil x CL**

***James T Volk***
*** ***

- 11/07/2002

**Notes:**
The STI Hall probe results showed a smaller X centerline motion than was measured on the SLAC spinning coil apparatus. For the spinning coil the initial increase of the centerline by 6 microns is a mystery. It may be due to the scanner or a real problem with the magnet. The Hall probe was rigidly mounted to the quad when it was measured at STI and it didn’t show substantial X centerline motion. Clearly, this will require further study.

## Phase II prototype

- Full size
- Engineered!
- Motorized
- 4 NEMA 17 servo motors
- Ethernet servo controller – Galil DMC2142
- Temperature compensated
- Preloaded Ball screws and linear guides
- 4X faster movement than NLC (neglecting eddy currents)
- Modular for flexibility
- Servo parts have been ordered
- Magnets, poles will be ordered soon

***James T Volk***
*** ***

- 11/07/2002

**Notes:**
The Phase II quad uses low backlash, high precision drive components. It will be tested at STI and elsewhere with both Hall probes and spinning coils. Operational experience will be very helpful in determining an NLC level design. The prototype will use four motors for maximum flexibility. A critical issue will be whether 4 motors are really needed or if two will suffice. The prototype test results will help make cost/performance tradeoffs.

## Preliminary Phase II Quad Design

***James T Volk***

- 11/07/2002

**Notes:**
This shows a ca. 40 cm long NLC quadrupole. The design allows the upper and lower halves to be separated for servicing and then relocated using pins. The figure shows four motors but depending on test results it may be possible to use two. The magnet brick arrays move on linear rails with a motor driven ball screw. Brick arrays are supported at their minimum deflection points (the Airy points). The blue part of the strongback assembly is Aluminum and the gray U-shaped part could be steel or Aluminum. Mechanical and thermal FEA are being performed now to determine deflections and make suitable adjustments to the mechanical stiffness of the structure as needed.

## Preliminary Phase II prototype schedule

- Engineering design complete March 2003
- Fabrication complete May 2003
- Testing starts May 2003
- Majority of prototype tests completed Sept 2003
- Spinning coil fabrication completed March 2003 (STI cost share)

***James T Volk***
*** ***

- 11/07/2002

## Halbach Ring Quad

- Poles

- Magnets

- Rotating
- ring

***James T Volk***
*** ***

- 11/07/2002

- LCRD Grant Proposal
- by J Rosenzweig
- To build one

## Failure Modes and Effects Analysis to Calculate 

** ****Life Cycle Cost for  NLC  Electro and Perm Magnets**

- $S

- $WC

**Water Cooled Coils **

**Solid Wire Coils**

- $SPS

- $LPS

**Magnet**

**Power Supply**

- $LPS

- 2nd Stage: Calculate Permanent Magnet Life Cycle Cost Mostly Using Component
- 	   Failure Rates         In Progress

- 3rd Stage: Compare 1st and 2nd Stage Results to Help Determine Magnet
- 	 Technology for NLC

***James T Volk***

- 11/07/2002

## Monte Carlo Simulation Variables: Detection Time, Fixing Time, 

**                      ****Delay Time, Quantity, Parts Cost**

**Life Cycle Cost (30yr) FMEA for Electromagnet with**
**Monte Carlo Simulation**

- ($)

- ($)

- ($)

- ($)

***James T Volk***

- 11/07/2002

## Estimating Frequency of Water Blockage from Empirical Data

**Estimating Frequency of Water Blockage from Empirical Data**
*Obtained failure history (CATER system) for 5 year period (1997-2001)*

**Expected Downtime ** = (1-Availability) x Operation hour/year
- (due to water flow blockages) = (1-0.999007) x 6480 hour/year
- 		       = **6.4 hour/year   ****(if NLC uses all electromagnets)**

**Occurrence **= Expected Downtime / MTTR
- 	      =  6.4 / 3.02 = **2.1 / year**

***James T Volk***

- 11/07/2002

## Estimate for Availability of all Power Supplies for NLC

**Estimate for Availability of all Power Supplies for NLC**

**Estimate for Availability of all Electromagnets for NLC**

**Estimating Overall Electromagnet System Availability for NLC**
**Magnets + Power Supplies (with redundant large PS )**

- Downtime for all types of magnet failures
- Total: 7167 Magnets

- Total: 6167 Power Supplies

- Availability =

***James T Volk***

- 11/07/2002

## Predicted Power Supply Life Cycle Cost

**Units: Million Dollars**

**Predicted Electromagnet Life Cycle Cost for 30 yrs **
**Using Monte Carlo Simulation ****(5000 runs)**

**Units: Million Dollars**

**# of correctors: 2202**
**# of water cooled magnets: 4965**

**# of small PS:  2785**
**# of large PS:  3382**

- 95% of the time the simulation predicts less than this amount

***James T Volk***

- 11/07/2002

## Radiation Damage

- Neodymium Iron Boron is an attractive material for use in Permanent magnets

***James T Volk***

- 11/07/2002

- Radiation damage issues

- Lower cost than Samarium Cobalt

- Higher energy density than Samarium Cobalt

- Less brittle easier to work with

- Not well measured especially for higher coercivity materials

- But not as resistant as Samarium Cobalt

- Issues with activation of Boron

- Need to test different manufactures and different coercivities

## Radiation Damage

- Radiation Damage to Permanent Magnets LCRD 2.24
- Lucien Cremaldi Unv. of Mississippi
- James Volk Fermilab
- Expose magnets to gamma rays
- Cs 137 662 KeV gamma 180 rad/hr    0.18 Mrad
- Co 60  1.16 MeV gamma 80 Krad/hr  80 Mrad

***James T Volk***
*** ***

- 11/07/2002

## Radiation Damage	

- Radiation damage studies of materials and electronic devices using hadrons LCRD proposal 2.9.1
- Dave Pellett and Max Chertok of UC Davis
- James Spencer of SLAC
- James Volk  of Fermilab

***James T Volk***
*** ***

- 11/07/2002

- Use the McClellan Nuclear Reactor Center (MNRC)
- in Sacramento and UC Davis Crocker Nuclear Lab at Davis
- Do both thermal and fast neutrons
- Use small quads that fit into rabbit holes
- Working on getting spectrum for damping rings and LINAC

## Radiation Damage	

***James T Volk***
*** ***

- 11/07/2002

- CIF 	Central Irradiation Facility
- PTS	Pneumatic Transfer System
- NTD	Neutron Transmutation Doping

- UC Davis MNRC Irradiation Facility

## MNRC Rabbit can

***James T Volk***
*** ***

- 11/07/2002

## Radiation Damage 

- 2.125”

- 1.125”

- Magnet material

- Gap (variable)

- Flux return

***James T Volk***
*** ***

- 11/07/2002

## Prototype of Radiation test quad

- Magnetic material

- Al spacers

- Gap for hall probe

- Direction of B orange arrow

- 11/07/2002

## Radiation Damage

- Beam pipe between 2 dipoles

- At Ring to LINAC Septum

- ceiling

- Calibration 107/sec

## Radiation Damage

- Have 2 grants in to study radiation damage in ND-Iron Boron
- Working up designs for magnets to fit available space
- Measuring spectrum in damping rings
- Expect to get some data on radiation damage by this winter
- Should have good data by Summer
- This will of course lead to more questions, experiments, grants, ...
- Present data at 18th International Conference on Magnet Technology in Oct 04?

***James T Volk***
*** ***

- 11/07/2002

## Future Plans

- Continue work on understanding and improving measurement system
- Work on motorized drives for PM quads
- Work on active correction coils for PM
- Continue reliability studies on EM and PMs
- Radiation damage studies

- 11/07/2002

## Summary

- Slow and steady progress on various adjustable quads
- Understanding measurement systems and make improvements
- Reliability studies continue
- Radiation damage studies beginning should have results by next MAC

***James T Volk***

- 11/07/2002