Outgassing Rate from CFRP-Al Honeycomb

SandwichTaku Yamanaka

Jan. 7, 2013@OSK

Evacuation rate

Evacuation rate is low

Still around 6Pa at the downstream

Komatsubara: CsI cover??

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Outgas measurement(set up by Togawa)

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My iPhone5

Reading Pressure4

angle (deg)

Pres

sure

(Pa)xSco

pe ru

ler

Sandwich sample

100 mm x 100 mm x 20 mm

1.5 mm thick CFRP on both sides

Same type with the cover that cracked

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Pumping rate

Slower pumping rate with sandwich plate

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Pa

Outgassing rate:empty

Close the chamber and measure the pressure rise

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Pa

Sandwich Outgassing rateHigher rate than empty

Lower rate as time passes

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Outgassing rate vs time since started pumping

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Is this serious?

0.5 Pa/min x 4 litters / 60s/min

x 3m2 / 0.01m2 = 10 Pa litter/sec

<< Outgassing rate for CsI PMT/CW/cables estimated by Lim-san: 240 Pa litter/sec

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After one day (24h) pumpingAfter one day (24h) pumpingO t ( it i t f ll d!)• One set (even it is not fully prepared!)– Outgas Q = 6.1X10-4 Torr�Liter/s/unitg– For 3000 Units : Q = 1.8 Torr�Liter/s

• Reaching PressureP Q/S (1 8 Torr Liter/s )/(566 Liter/s)P = Q/S = (1.8 Torr�Liter/s )/(566 Liter/s)

= 3.2 X 10-3 Torr= 0.42 Pa

G.Y. Lim (KEK), 5/28/2010

Outgassing rate Q = 1.8 Torr litter/s = 240 Pa litter/s

Photo of a part of one setPhoto of a part of one setPMT�for�large�CsI

LAN bl (10 )g

LAN�cable�(10m)

STP�cable�(60cm)

CW bCW�base

Flat�cable�(2X2m)

Things to do

Cover the surface of CFRP with Kapton tapes to check where the outgas is coming from.

Try the sandwich (smaller honeycomb cell size) used for the actual cover.Prepare slides for the PAC on 1/9

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