Absorber Design Details

Mary Anne Cummings

MICE MEETING

Columbia

June 13, 2003

What details?

1. Windows (absorber and vacuum)

2. TPG high voltage concerns (and other electrical concerns)

3. Off-center options

4. Installation scenario

5. Testing procedure

Window requirements

FNAL Requirements (vacuum):

1. Burst test 5 vacuum windows at room temp. to demonstrate a burst pressure of at least 75 psid for all samples. (pressure exerted on interior side of vacuum volume).

2. Non-destructive tests at room temperature:

a. External pressure to 25 psid to demonstrate no failures: no creeping, yielding, elastic collapse/buckling or rupture

b. Other absorber vacuum jacket testing to ensure its integrity

FNAL Requirements (absorber)1. Room temp test: pressurize to burst ~ 4 X MAWP (25 psi2. Cryo test:

a) pressure to below elastic limit to confirm consistency with FEA results

b) pressure to burst (cryo temp – LN2) ~ 5 X MAWP from ASME: UG 101 II.C.3.b.(i)

Plus non-destructive certification New review required if the windows are welded!!

H2

VAC

LH2 Instrumentation

4/24/2003 19

(basic) Barrier

Power+

Signal

Return

Ground

“safe circuit”

fuse

Flammable Gas Electrical Safety

4/24/2003 23

Two Possibilities (1)

• Intrinsically safe

UPS

PC w/16 chan ADC

FISO

Cryo(temp)

IRM

Barrier(s)

network

ACNET

Sealed Conduit(s)

Intrinsically safe signal conditionersand transmitters

power

Hazard Safe

4/24/2003 24

Two Possibilities (2)

• Gas-purged box

UPS

PC w/16 chan ADC

FISO

Cryo(temp)

IRM

Barrier(s)

network

ACNET

Sealed Conduit(s)

power

Hazard Safe

Concerns for detectors: Power per channel Feedthroughs Seals

1. Scenario (2) is the configuration that would be consistent with a safe TPG detector installation.

2. All electronics will have to conform to European safety standards w.r.t. flammable gas.

3. RF & Vacuum windows considered a “hazard/safe” barrier.

4. “Gas-purged” box necessary for non-instrinsically safe electronics within 15 ft. radius of hydrogen (FNAL code)

Current conclusion: not a problem – yet!

Off center solid absorber issueOff center absorber position:

> what is the change in 0 - 1 / 0?

< 20% if the absorber had no longitudinal extent

R

nn

LmEEds

dE

ds

d

2

)014.0(11 2

32

Schedule and assembly

• Assembly:– Windows manufacture/testing NIU/FNAL

– KEK fabricate the absorber heat exchanger associated piping connections and absorber vacuum chamber

– NIU/IIT fabricate outer containment vessel, supports, windows for vacuum and absorber,

– LBNL/Oxford provide the focussing coils with coils support structures.

– Absorber assembly/testing at FNAL

– Coil assembly and absorber integration at RAL

Testing procedure

1. Window tested separately

2. Windows tested on absorber (leak checks)

3. Field measurements of coils

4. Purging and filling cycle

5. Instrumentation check and stability monitoring