PDR Vacuum Spool Clearances Check

T. Brown

September 1, 2003

VV spool assembly clearance space allocation goal

1.00 VV insulation

0.25 minimum gap at final position (also makes up part of the space needed for final assembly in the area of the VV spool piece)

0.188 VV fabrication tolerance (3/16”)

0.06 MC fabrication tolerance (1/16”)

1.50”

0.25” Additional assembly tolerance for final assembly (this value is 0.75” for the assembly of the MC over the VV).

1.75” Target clearance set for the MC to VV spacing in spool region

Ref VV-06 basic spool

0

0.5

1

1.5

2

2.5

3

3.5

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55

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Basic spool

Spool w ith w eld prep

1.319” clearance

Reverence VV-06 vessel spool had 1.50 clearance to MC during assembly. With weld prep added to basic VV-06 spool the clearance degraded to 1.32”

Note: We accepted the 1.5” clearance because we were expecting a .25” build reduction in the Type C MC.

Ref VV-06 basic spool

PDR baseline

spool

Spool altered to eliminate crease

New PDR spool shape exceeds original boundary in some areas

Baseline PDR Vacuum Vessel and Module Coil clamp envelope

Component Build Dimension Comparison

0.388

1.50 (1.0 insulation + 0.25 gap + 0.188 VV tol + 0.06 MC tol)

1.0

0.787

Plasma

PFC’s

Vacuum Vessel

4.671

4.10

5.100

0.375

1/8 VPI layer

3/8

2.3362.836

0.375 (9.5 mm)

Clamp

Winding

2.175 (55.2 mm)

2.961

VPI layer ?

The clamp is .125” thicker but a large corner radii HELPS the spool assembly

Reference Build PDR Build

PDR Spool peice

0

0.5

1

1.5

2

2.5

3

3.5

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65

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PDR Spool peice

1.060” low side

ProE clearance study results

(this took a 2 hr run!)

The two servos driving the spool are not properly adjusted to arrive at a maximum clearance value (see next slide).

1.060” low side

2.068” high side

1.564 average

Servo’s can be adjusted to obtain an average minimum clearance of 1.56 inches between the MC and new PDR VV spool piece.

2.961

Per discussion with Brad, the VPI layer is under the

clamps

1.75” Target clearance that initially was set for the MC to VV spacing in the spool region can be reduced if the spool tolerance is changed to +0 / -.06;

or we can increase the clearance by going back to a 3/8” thick clamp.

Is 1.56” clearance OK?

0.5 Jim C needs 0.5” assembly gap at spool for final assembly

0.00 change VV spool tolerance to +0 / -.060

0.06 MC fabrication tolerance

1.00 Insulation

1.56” This will work!