Reports 1-1 of 1 Clear search Modify search
VAC (SRM)
nobuhiro.kimura - 6:35 Friday 24 April 2026 (36813) Print this report
Pressurization of SRM to atmospheric pressure

Date of work:
23, Apr, 2026
 
Workers:
Kimura and Tomaru
 
Abstract:
 We pressurized SRM atmospheric pressure for the investigation of outgassing source in SRM (k-log 36811).
The following is a record of the opening and closing of valves and the pressure of the pressurization process.
The same process is used for k-log 26030. It is noted here for reference.
 
~9:50 GVoomt Close
          Set safety valve to SRM vacuum pump unit
          Turn on main SW of TPM (Not acceration, only raise the rotor blades to protect the TMP)
9:55    Pressurization was  started by G-2class grade air (klog-25912).   Cylinder is filled with 7 m³ of compressed dry air.
          Pressure inside SRM was    1.7 x 10^1 Pa    Cylinder pressure 15.2 MPaG
10:00          "                         2.1 x 10^3 Pa
10:22          "                         3.7 x 10^3 Pa
10:33          "                         4.2 x 10^3 Pa    Cylinder pressure 14.2 MPaG
10:40          "                         7.8 x 10^3 Pa
10:55          "                         1.6 x 10^4 Pa    Cylinder pressure 11.9 MPaG
11:21          "                         3.3 x 10^4 Pa                "               8.9 MPaG
11:30          "                         3.9 x 10^4 Pa                 "              7.9 MPaG    Increased air flow  (Secondary pressure 1.1  kg/cm^2G) 
11:34          "                         4.1 x 10^4 Pa                 "              7.5 MPaG
11:54          "                         5.3 x 10^4 Pa
12:12          "                         6.4 x 10^4 Pa
12:12          "                         6.4 x 10^4 Pa
12:19          "                         6.9 x 10^4 Pa
12:27          "                         7.4 x 10^4 Pa    Cylinder pressure   2.0 MPaG
12:34          "                         7.8 x 10^4 Pa                 "              1.1 MPaG
Change to a new cylinder filled with 7 m³ of compressed dry air
12:41          "                         7.9 x 10^4 Pa    Cylinder pressure   15.2 MPaG
12:45          "                         8.1 x 10^4 Pa                 "              15.1 MPaG
12:53          "                         8.4 x 10^4 Pa
12:58          "                         8.9 x 10^4 Pa
13:02          "                         9.0 x 10^4 Pa                "               13.2 MPaG
13:04          "                         9.1 x 10^4 Pa
13:07          "                         9.4 x 10^4 Pa               "                12.6 MPaG
13:10          "                         9.6 x 10^4 Pa
13:11          "                         9.7 x 10^4 Pa
  The pressurization process is terminated because the pressure in the SRM has reached almost atmospheric pressure at 13:11. 
Based on the volume of dry air, the internal volume of the SRM was estimated to be approximately 9 m³.

Comments to this report:
hiromi.yasui - 17:30 Friday 24 April 2026 (36817) Print this report

[mTakahashi, hSawada, Nakagaki, Yasui]

1. Vacuum evacuation by DSP
We tightened top- and +X-side- flanges of SRM, and started pumping down by the Dry Pump.

10:20 Turned ON the dry pump
10:26 Opened the angle valve: 270 degrees
10:38 6.8×10^4Pa
11:06 2.9×10^4Pa
11:14 Opened the angle valve: 450 degrees
11:30 9.2×10^3 ->Opened the angle valve fully
11:36 6.6×10^3Pa
11:47 3.7×10^3Pa
13:25 6.6x10Pa
13:37 5.3x10Pa
13:56 4.0x10Pa
14:09 3.3x10Pa


2. Leak check of Q-mass
Also, we had a leak test around Q-mass that installed yesterday.
Since the leak level was less than 1×10^-13Pam^3/s, we opened the valve and connected to the OMMT chamber.

3. Vacuum evacuation by TMP
After rough pumping by the dry pump, I started evacuating by the TMP.       

  SRM[Pa] OMMT[Pa]
14:38 2.4x10 5.3x10^-1
14:39 GVommt OPEN
  1.3x10 1.4x10
14:40 TMP START
14:44 1.2x10 1.3x10
14:51 1.8x10^-2 2.2x10^-2
Search Help
×

Warning

×