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Message ID: 468     Entry time: Tue Nov 5 11:08:40 2024
Author: Luis Martin 
Type: Update 
Category: VAC 
Subject: ISO Test 

[Luis, Luke, Ma Michael]

The isolation test was conducted on the vacuum system. Every pump was turned off under vacuum, and pressure measurements were taken every minute for 15 minutes. The results are displayed in the sheet linked at the end of this report. The pressure of the main volume dropped very slowly.

The pressure of the RGA Volume dropped in an exponential manner. The test had to be paused at 11 minutes due to concerns about the pressure exceeding the lowest permitted level for the RGA filament.

After the ISO test was performed, we attempted to tighten the bolts of the small turbo pump on the RGA Volume. However, we noticed that the pressure had increased by nearly an order of magnitude, going from 3.27 × 10-9 Torr to 1.45 × 10-8 Torr when both volumes were separated. We conducted a leak test for that particular flange and found a concerning leak of 2.15 × 10-8 Torr, which had previously been 1.9 × 10-9 Torr. We believe the copper seal was damaged during the ISO test.

View the results sheet

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