# Presentation: 550118

## Long racetrack supporting structure

- Paolo Ferracin and Dan Cheng
- LARP Collaboration Meeting
- LBNL
- April 26 - 28, 2006

## Outline

- Introduction
- Magnet design
- Assembly and pre-loading
- Magnetic analysis
- Mechanical analysis
- Test plan
- Current status and next steps

- Paolo Ferracin

- 04/26/2006

## Introduction

- Task goals
- Provide supporting structure for test of 4 m long racetrack coils
- Develop a shell-based supporting structure for long magnets
- Steps
- Design, procure the structure
- Define a procedure for assembly and disassembly
- Test structure at LBNL with dummy coils
- Check uniform load with
- Strain gauges mounted on the shell
- Pressure sensitive films
- Ship structure to BNL
- Design based on the support structure for the SM program

- Paolo Ferracin

- 04/26/2006

## Outline

- Introduction
-  Magnet design
- Assembly and pre-loading
- Magnetic analysis
- Mechanical analysis
- Test plan
- Current status and next steps

- Paolo Ferracin

- 04/26/2006

## LR cross-section

- With respect to SM design
- Aluminum shell
- Larger diameter: 305 mm
- Thicker iron yokes
- Bigger yoke gaps
- Simplified iron pads
- Thicker stainless steel skins
- 2 bladders and 4 loading keys for assembly and pre-load
- 2 pull shims for bladder removal

- Paolo Ferracin

- 04/26/2006

## LR 3D design

- Aluminum shell
- Single piece
- Length:  3.6 m
- Iron yokes
- 50 mm thick laminations
- Iron pads
- Half length (1.8 m)
- Stainless steel skins
- Full length (3.6 m)
- Bladders
- Half length (1.8 m)
- Keys and shims
- Half length (1.8 m)

- Paolo Ferracin

- 04/26/2006

## Outline

- Introduction
- Magnet design
-  Assembly and pre-loading
- Magnetic analysis
- Mechanical analysis
- Test plan
- Current status and next steps

- Paolo Ferracin

- 04/26/2006

## Assembly-related components

- Handling rafts can be configured for installation operations as well
- Installation beam

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Raft and bottom cradles placed onto ~25’ of granite/surface table
- Aluminum shell is placed into cradles
- Upper raft is configured into installation fixture

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Cantilever portion of installation raft is then inserted into the empty aluminum shell
- Yoke half lamination is assembled on non-inserted portion of the installation beam
- Yoke half is inserted into the shell

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Raft is disconnected and reconfigured
- Pull shims inserted
- Compact cylinders are pressurized to 300 psi
- Applies small load keep yoke from shifting during rotation operation
- Rotate assembly
- Two-crane (or main/aux. hook) operation
- Or rotation wheels
- Remove top raft
- Bleed pressure

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Reconnect installation beams to handling raft
- Pull assembly beam from shell internals
- Remove internal cradle supports
- Reinsert installation beam
- Rinse, lather, repeat:
- (Assemble 2nd yoke half, insert)

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Pressurize cylinder manifold to 300 psi
- Insert gap keys (and necessary shims)
- Bleed cylinder pressure
- Remove installation beam from center
- Yoke halves are now only resting on gap keys

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Reconfigure installation raft
- Replace beam standoffs
- Remove cantilever installation beam

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Align installation beam slots to yoke key slots
- Insert coil pack onto beam w/keys

- Paolo Ferracin

- 04/26/2006

## Assembly Process

- Insert pull shims with bladders
- Load yokes with bladder pressure
- Insert necessary shims
- Remove gap keys, etc. from between yokes
- Bleed HP

- Paolo Ferracin

- 04/26/2006

## Outline

- Introduction
- Magnet design
- Assembly and pre-loading
-  Magnetic analysis
- Mechanical analysis
- Test plan
- Current status and next steps

- Paolo Ferracin

- 04/26/2006

## 2D magnetic analysisFlux lines and peak field

- “Common-coil” (quadrupole) flux line profile
- Peak field located in the inner surface of the coil, approximately between turn 11 and turn 13.

- Paolo Ferracin

- 04/26/2006

## 2D magnetic analysisMagnet parameters

- Jc (4.2 K, 12 T) = 2800 A/mm2
- Cu/SC = 0.9
- Bpeak (4.2 K) = 12.2 T
- Iss (4.2 K) = 10.8 kA
- Stored energy (4.2 K) = 86 kJ/m
- Inductance (4.2 K) = 1.5 mH/m

- Paolo Ferracin

- 04/26/2006

## 3D magnetic analysisField in the ends

- The field decreases from 12.2 T at the center to 11.6 T at the end of the straight section
- In the end region, the field further decreases to 11.0 T

- Paolo Ferracin

- 04/26/2006

## Outline

- Introduction
- Magnet design
- Assembly and pre-loading
- Magnetic analysis
-  Mechanical analysis
- Test plan
- Current status and next steps

- Paolo Ferracin

- 04/26/2006

## 2D mechanical analysisLorentz forces

- At short sample current
- Fx (quadrant) = + 1903 kN/m
- x = 62 MPa
- Fy (quadrant) =  - 9 kN/m
- y < 1 MPa

- Paolo Ferracin

- 04/26/2006

## 2D mechanical analysisCoil horizontal stress

- After cool-down
- About 30 MPa coil pre-stress

- At full field
- 75 MPa of coil max. stress

- Paolo Ferracin

- 04/26/2006

## 2D mechanical analysisTolerance analysis

- Tolerance of the components
- Shell ID
- -0.000” / +0.0025”
- Yoke OD
- -0.003” / +0.000”
- Yoke key slot
- - 0.002”/ +0.002”
- Pad thickness
- -0.003” / +0.003
- Total range
- -0.008” / +0.008

- Paolo Ferracin

- 04/26/2006

## 3D mechanical analysisMechanical model

- 3D geometry
- Full length
- Interaction between shell and yoke in the axial direction
- Straight section of 300 mm
- Effect of axial Lorentz forces on the contact area coil-island

- Paolo Ferracin

- 04/26/2006

## 3D mechanical analysisContraction of aluminum shell

- 4 m long shell
- Shell azimuthal stress at 4.3 K
-  = 150 MPa
- Frictionless model
- Shell *z* contraction = 9.5 mm
- (αshell  lshell) + ( / Eshell    lshell)
- Yoke *z* contraction = 3.9 mm
- (α yoke  lyoke)
- Relative z shell-yoke = 5.6 mm
- Friction model (μ = 0.2)
- Shell *z* contraction = 5.7 mm
- Yoke *z* contraction = 4.2 mm
- Relative z shell-yoke = 1.5 mm

**Friction = 0.2**

**Friction = 0.0**

- Paolo Ferracin

- 04/26/2006

## 3D mechanical analysisCoil-island contact region

- Frictionless model
- After cool-down
- Coil: z = + 20 MPa
- Island: z = - 50 MPa
- Fz contact = ~ 20 kN
- Still contact at high field

- Paolo Ferracin

- 04/26/2006

## 3D mechanical analysisCoil-island contact region

- Friction model
- After cool-down
- Fz contact = ~ 10 kN
- Friction is limiting axial motion
- Still contact at high field

- Paolo Ferracin

- 04/26/2006

## Outline

- Introduction
- Magnet design
- Assembly and pre-loading
- Magnetic analysis
- Mechanical analysis
-  Test plan
- Current status and next steps

- Paolo Ferracin

- 04/26/2006

## Test plan

- Insertion of pressure sensitive films
- Dummy coils – skins
- Load keys – yoke/pads
- Strain gauges
- Mid-plane (both sides)
- 5 axial locations
*Y *and *Z *directions
- Temperature compensators
- Total: 40 gauges
- Pressurize bladders and insert keys in several steps
- Monitor stress level and uniformity
- Inspect pressure sens. films

- Paolo Ferracin

- 04/26/2006

## Outline

- Introduction
- Magnet design
- Assembly and pre-loading
- Magnetic analysis
- Mechanical analysis
- Test plan
-  Current status and next steps

- Paolo Ferracin

- 04/26/2006

## Current status (I)

- Engineering design of all the components completed
- Magnetic analysis
- Computation of peak field, load line, and field in the ends
- Mechanical analysis
- Stress in the coil after cool-down and at high field
- Effect of fabrication tolerances
- Sliding between shell and yoke
- Contact coil-island during excitation
- Assembly procedure defined
- Procurement
- Aluminum shell, tie rods, dummy coils available
- Yoke and pads by the end of May

- Paolo Ferracin

- 04/26/2006

## Current status (II)

- Paolo Ferracin

- 04/26/2006

## Next steps

- May
- Finalize handling structure design & detail drawings
- Handling rafts (detail drawings in progress)
- Cradles (detail drawings in progress)
- Winch mounts & pulling structure (to be designed)
- Instrument shell with strain gauges
- June - July
- Magnet assembly
- Load test

- Paolo Ferracin

- 04/26/2006