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venting_pumping_intermediate_image_box [2018/12/19 11:10] pereira [Filling Intermediate-image delay PPAC] |
venting_pumping_intermediate_image_box [2024/01/11 10:29] noji [Emptying Detectors] |
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- | ====== Venting/ | + | ====== Venting/ |
* [[#General information]] | * [[#General information]] | ||
- | * [[#Vent Intermediate-image chamber|Venting Intermediate-image chamber]] | + | * [[#Emptying Detectors]] |
- | * [[#Pumping Intermediate-image chamber]] | + | * [[#Filling and Running Detectors]] |
- | * [[#Filling Intermediate-image delay PPAC]] | + | * [[#Troubleshooting]] |
===== General information ===== | ===== General information ===== | ||
- | The procedures to vent/pump the S800 Intermediate Image box, and/or filling the PPAC detectors with gas must be done carefully to ensure that the PPACs are not damaged. For instance, before venting the chamber, we have to make sure that the PPACs are empty and equalized with respect to the vacuum in the chamber. In order to avoid errors, an automated gas handling system (II-GHS) was designed to perform these tasks safely. | + | The procedures to vent/pump the S800 Intermediate Image box, and/or filling the PPAC detectors with gas must be done carefully to ensure that the PPACs are not damaged. For instance, before venting the chamber, we have to make sure that the PPACs are empty and equalized with respect to the vacuum in the chamber. In order to avoid errors, an automated gas handling system (II-GHS) was designed to perform these tasks safely. The II-GHS equipment (valves, flow-meter, pipes, isobutane gas bottle. etc.) are located on the west balcony of the top level in the S3 vault (see figure below): |
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- | The II-GHS equipment (valves, flow-meter, pipes, isobutane gas bottle. etc.) are located on the west balcony of the top level in the S3 vault (see figure below): | + | |
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+ | {{: | ||
+ | The GHS is operated remotely through CS studio. Its page can be found on the EXP network through FRIB EXP Main → S800 → GHS Pages (Secondary Pages) → Intermediate Image PPAC and is shown below. | ||
- | ===== Vent Intermediate-image chamber ===== | + | {{:wiki: |
- | Requirements: PanelMate files **S3_Gas_Handling** and **S800Vac** | + | |
- | * Verify that PPACs are in automatic mode with gas removed (**S3_Gas_Handling**) | + | The layout |
- | * | + | |
- | * If gas is removed but the system is not in the automatic mode, consult the Beam Physicists or Device Physicist. NOTE: the only valves that should be open in **S3_Gas_Handling** are the "Det Bypass" | + | |
- | * Verify that PPACs are not biased: | + | |
- | * Check that the detectors are unbiased by opening the [[HV bias|HV GUI]] | + | |
- | * Notify the system | + | |
- | * Open **S800Vac** and go to page 03 (" | + | |
- | * Isolate chamber by closing gate valves **I212GV** and **I215GV** | + | |
- | * [[Vacuum control|Turn off]] ion gauge **I213IG** | + | |
- | * Check box " | + | |
- | {{: | + | |
- | * In order to begin venting process, select box "VENT STATUS" | + | |
- | * Box "VENT STATUS" | + | |
- | * Turbo gate valve **I214GV** will be automatically closed and pressure in chamber will start rising (as seen in **I215PG**) {{: | + | |
- | * When **I215PG** reads atmospheric pressure, select the box "VENT STATUS" | + | |
- | * The status in the box "VENT STATUS" | + | {{: |
- | * You can now open the chamber | + | |
+ | The operational states of the II-GHS are shown in the diagram below. | ||
- | ===== Pumping Intermediate-image chamber ===== | + | {{:wiki:ii-ppac-ghs-operationalstates.png|}} |
- | Requirements: PanelMate files **S3_Gas_Handling** and **S800Vac** | + | |
- | * Verify that Chamber is closed and pressure-relief valve (north side of the chamber) is properly closed (NOTE: sometimes, due to overpressure from dry N2 during the venting procedure, the O-ring in pressure-relief valve flange is moved out of place) | + | |
- | * Verify that PPACs are not biased by opening the [[HV bias|HV GUI]] | + | |
- | * IMPORTANT: Verify that manual roughing pump valve located near the intermediate-image chamber is closed{{: | + | |
- | * Insert PPACs/turn on light (Diagnostic Drives PanelMate) and verify condition through sight window on south side of the chamber (be careful no to bump the bullet camera). | + | ===== Emptying Detectors ===== |
- | * Open **S800Vac** and go to page 03 (" | + | - Set “PPAC Setpoint” |
- | * Check " | + | |
- | | + | |
- | * Start slow (< 1 Torr/sec). Chamber pressure is displayed in **I215PG** in **S800Vac** PanelMate. There is also a local display of the mechanical pump pressure on a Granville-Phillips 275 Mini-Convectron, | + | |
- | * Verify PPACs changing shape through sighting window. | + | - Valves #1-5 should |
- | * Pump to about 100 Torr before fully opening | + | * Jorge noted on 2/12/2023 that this step did not work; he reported that when he clicked **PUMP** nothing happened. Instead, he had to “manually” enter the PV name associated with this command |
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- | * When the pressure in **I215PG** is below 200 mTorr, the Turbo Pump will start automatically through the following sequence: | + | |
- | * **I214RV** will be closed | + | |
- | * **I214FV** will be opened | + | |
- | * **I214GV** will be opened | + | |
- | * When the pressure ready by **I215PG** is few mTorr, you can turn on the ion gauge **I213IG**. Good vacuum will take ~1-2 hours. | + | |
- | | + | |
- | * Select box labeled " | + | |
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- | * When foreline vacuum gets below 2 Torr, you can select " | + | |
- | * (Note: sometimes it is necessary | + | |
- | * At the end of the procedure, close the manual roughing pump valve | + | |
+ | ===== Venting the Chamber ===== | ||
+ | From the S800 Main Vacuum page, go to the Intermediate Image - RBT_BTS32 D2430 Pumping Station page, and ensure | ||
+ | * that the PPACs have been unbiased, | ||
+ | * that this pumping station has been isolated by having the gate valves **D2426 BGV** and **D2436 BGV** closed, and that the IG has been turned off, and | ||
+ | * that the turbo pump gate valve TVG is closed. | ||
+ | To vent the chamber: | ||
+ | - Monitor **RBT_BTS32: | ||
+ | - close **RV**, the valve to the roughing pump, and | ||
+ | - open **Vent**. | ||
- | ===== Filling Intermediate-image delay PPAC ===== | + | The PPAC pressure S800_GHS: |
- | Requirements: | + | RBT_BTS32: |
+ | ===== Evacuating the Chamber | ||
- | * Verify that PPACs are in automatic mode with gas removed (**S3_Gas_Handling**) | + | {{: |
- | * The "GH System Status box should read " | + | ===== Filling and Running Detectors ===== |
- | * If gas is removed but the system | + | - If in Vent Mode, click **PUMP** then click **RUN** to enter Run Mode. |
+ | - If in Pump Mode, click **RUN** to enter Run Mode. | ||
+ | - Plot and monitor IG_D2430: | ||
+ | - Step up “PPAC Setpoint” by 1 Torr from 0 to 6 Torr. Allow the “PPAC Pressure” to stabilize for 15 seconds at each step. This should be a quick process but **DO NOT** simply set the “PPAC Setpoint” to 6 Torr as the gas flow could overwhelm | ||
+ | - PPAC pressure should stabilize after ~1 min. HV may now be turned on to operate | ||
+ | ===== Troubleshooting ===== | ||
+ | - If any issues are encountered during filling, running, or emptying, contact the Vacuum Operation group for assistance. |