# Presentation: 933010

## Summary of Low Cost Fabrication of Integrated Coil Structure

**Summary of Low Cost Fabrication of Integrated Coil Structure**

**L. M. Waganer**
**With Support from**
**Kevin Slattery and John Waldrop-III**
**The Boeing Company**
**ARIES Project Meeting**
**PPPL, Princeton, NJ **
**4 October 2006**

## Summary of Advanced Fabrication of the Coil Structure

**Mass: ~ 3 x 10****6**** kg for 3 field periods**
**Construction: Monolithic for entire field period **
**Fabrication Location: At construction site**
**Fabrication: Additive machining – arc deposition of near net shape, final machining of coil grooves by robot milling machines on inner surface and field period interfaces**
**Coil Fabrication: Coil cables will be wound into the grooves with robot winding machines**
**Accuracy of Coils: EM forces will be analyzed to determine displacement.  Placement of the grooves will be compensated so the coils will be in proper location when coils are energized.**

**Summary of Advanced Fabrication of the Coil Structure**

**Interior grooves show on exterior for clarity**

## Nominal Cross-Section

**This is the nominal coil cross-section to be fabricated. The thicknesses will vary depending on the predicted local EM forces, thicker inboard and thinner outboard.**

**28 cm**

**20 cm**

**Strongback**

**Inter-coil Structure**

**Range 10 to 35 cm**

**Range 20 to 45 cm**

**Coil dimensions**
**18.4 cm x 67.2 cm**

**Cover plate 5 cm thick**

## Volumetric Heating the Coil Structure

**The volumetric heating is relatively low in the coil structure. Cooling with intimately joined coolant lines is quite adequate for the level of heating. This approach is quite reliable, very low cost, and compatible with fabrication approach.   Moreover, the location of the tubes can be adjusted to local heating fluxes. **

**Cooling the Structure**

**Intercoil****Structure**

**Strongback****Structure**

## Plasma Arc Deposition

**The deposition wire is fed into the plasma arc and the material deposited in layers**

**Overhanging features can be created with cooled slip plates**

**Planar Features**

**Overhanging Features**

**Near net shape grooves can be created as the material is deposited by starting and stopping the deposition.  These features require only minimal machining.  All other surfaces probably will require no machining.**

**Near Net Shape Grooves**

## Groove Fabrication

**Guide rails and fiducial reference datums will be added to the structure parts to guide the milling machines for final groove machining. **

**A similar machine will use the same rails and fiducial datums to install the superconducting cables into the coil groove**

**After all the cable is in place for the coil, the cover place will be installed and friction-stir welded in place to secure the coil.**

## Concept to Fabricate Structure

**Start with solid base**
**Begin to create structure**
**Continue to add layers**
**Ditto**
**Until it is complete for a field period**

## Staging of Field Period Structures

**Multiple deposition robots will be required to build a field period in roughly a year **
**Each deposition robot will be assigned a zone to build**

**Plan  View**

## Preliminary Costing

** ****A preliminary **_**engineering **_**cost estimate has been developed **
** ****Additional detail can be added as needed**
** ****Costs will be presented in $2006**
**Total mass is 10****6**** kg ****(393m****3**** x 7800 kg/m****3****)**
** ****Cost of specialty steel, JK2LB, in wire form is $20/kg ****(estimate)**
** ****Build each segment (FP) separately in sequence**
** ****Build Time is driven by deposition rate, but is adjustable by using more robots ****(10 assumed)**

## Cost of Deposition

**Today’s price estimate**

**Assumption of 10 robots**

**Driving schedule item**

**Representative **
**robot cost**

**Highest Cost Element**

## Cost of Stress Relief

**Typical low temp time**

**Minimal operators**

## Cost of Coil Channel Machining

**CAD determination**

**3 operators + QA**

**Probably high**

**Arbitrary number**

## Cost of Coil Cable and Cover Installation

**Arbitrary number**

**Arbitrary number**

## Cost of Cooling Channel Machining

**Arbitrary size**

**This is a representative way of cooling the structure using machined channels with a friction stir welded cover plate.  **

## Cost of Cooling Channel Closeout

**Cost of Cooling Channel Closeout**

**Arbitrary size**

**This is a representative way of cooling the structure using machined channels with a friction stir welded cover plate.  **

## Summary Schedule and Costs

**This is a good approximation of the coil structure fabrication cost using advanced low cost techniques that will have no complexity factor.   This compares to much more expensive conventional fabrication approach that has high labor costs and significant complexity factors.**

**~ 2.4 yr fabrication**

**Labor costs are < 1⁄2 the cost of raw material costs!**

## Low Cost Fabrication Slides for Engineering Summary

## Summary of Advanced Fabrication of the Coil Structure

**Mass: ~ 3 x 10****6**** kg for 3 field periods**
**Construction: Monolithic for entire field period **
**Fabrication Location: At construction site**
**Fabrication: Additive machining – arc deposition of near net shape, final machining of coil grooves by robot milling machines on inner surface and field period interfaces**
**Coil Fabrication: Coil cables will be wound into the grooves with robot winding machines**
**Accuracy of Coils: EM forces will be analyzed to determine displacement.  Placement of the grooves will be compensated so the coils will be in proper location when coils are energized.**

**Summary of Advanced Fabrication of the Coil Structure**

**Interior grooves show on exterior for clarity**

## Plasma Arc Deposition

**The deposition wire is fed into the plasma arc and the material deposited in layers**

**Overhanging features can be created with cooled slip plates**

**Planar Features**

**Overhanging Features**

**Near net shape grooves can be created as the material is deposited by starting and stopping the deposition.  These features require only minimal machining.  All other surfaces probably will require no machining.**

**Near Net Shape Grooves**

## Groove Fabrication

**Guide rails and fiducial reference datums will be added to the structure parts to guide the milling machines for final groove machining. **

**A similar machine will use the same rails and fiducial datums to install the superconducting cables into the coil groove**

**After all the cable is in place for the coil, the cover place will be installed and friction-stir welded in place to secure the coil.**

## Concept to Fabricate Structure

**Start with solid base**
**Begin to create structure**
**Continue to add layers**
**Ditto**
**Until it is complete for a field period**

## Staging of Field Period Structures

**Multiple deposition robots will be required to build a field period in roughly a year **
**Each deposition robot will be assigned a zone to build**

**Plan  View**

## Preliminary Costing

** ****A preliminary **_**engineering **_**cost estimate has been developed **
** ****Additional detail can be added as needed**
** ****Costs will be presented in $2006**
**Total mass is 10****6**** kg ****(393m****3**** x 7800 kg/m****3****)**
** ****Cost of specialty steel, JK2LB, in wire form is $20/kg ****(estimate)**
** ****Build each segment (FP) separately in sequence**
** ****Build Time is driven by deposition rate, but is adjustable by using more robots ****(10 assumed)**

## Summary Schedule and Costs

**This is a good approximation of the coil structure fabrication cost using advanced low cost techniques that will have no complexity factor.   This compares to much more expensive conventional fabrication approach that has high labor costs and significant complexity factors.**

**~ 2.4 yr fabrication**

**Labor costs are < 1⁄2 the cost of raw material costs!**