Cornell High Energy Synchrotron Source
Doc#: SOP-OPS-001 ||
Procedure: Helium Supply Maintenance ||
Prepared by: ZB |
Rev.: 3 ||
Revision Date: 2/17/14 ||
Date Effective:02/17/14 ||
Date Expires: 02/17/15 ||
Approved by: DJJ |
To replace an empty Helium crib with a fresh backup to provide a continuous Helium supply to CHESS areas.
Materials and Equipment Needed
- New High-Purity Helium 12-pack
- Pallet Jack
- 1-1/8” Wrench
- Leak Checking Liquid
- Scrap Paper
- Scotch Tape
- Hazards – Pressurized gas.
- Safety Equipment Required: none
- Acknowledge alarm at ops.
- Walk to He Supply station in L0E and verify that the MAIN tank capacity is low with the in-line Pressure gauge on the wall panel.
- Determine which He crib is on Main (A/B). If the selector handle in the center of the wall panel is horizontal, A is on MAIN and B is on BACKUP. If the handle is vertical, B is on MAIN and A is on BACKUP. (Fig. 1)
- Close all twelve valves on the cylinders in the crib.
- Close the main output valve located in the top-center of the MAIN crib. (Fig. 2)
- Close the MAIN LINE VALVE located above the wall panel. (Fig. 3)
- Close the intermediate valve on the wall-panel from the MAIN crib. (Fig. 4)
- Loosen and remove the nipple from the crib’s main valve and hang the hose on the holder marked CGA-580 HOLDER next to the MAIN LINE VALVE using the 1-1/8” wrench.
- Move the empty crib away from the supply station to a temporary location using the pallet jack,.
- Sweep the area where crib was located.
- Move the spare crib (right-most looking at the supply station) into the empty bay with the main valve aligned with the wall panel using the pallet jack.
- Mark that the He crib is empty on the paper, with operator initials and date using the marker and scrap paper.
- Tape the sign to the empty crib.
- Move the empty crib into the bay where the spare previously sat with the EMPTY sign facing outwards.
- Remove shrink-wrap from the new crib’s main valve.
- Remove the CGA-580 nipple and hose from the wall holder and connect the hose to the new He crib’s main valve.
- Tighten the nut using the 1-1/8” wrench.
- Open all twelve (12) valves on the Helium cylinders.
- Open the main valve of the Helium crib SLOWLY.
- Open the intermediate valve between the wall panel and the crib.
- SLOWLY open the Main Purge Vent dial and bleed the line for 30 seconds. (Fig. 3)
- Close the Main Purge Vent.
- Open the MAIN LINE VALVE.
- Switch the new tank to BACKUP:
- Turn the handle on the wall-panel 90 degrees such that the pointed side of the handle is pointing towards the appropriate MAIN/BACKUP label.
- Leak-check the new crib’s main valve:
- Spray Leak Checking Liquid between the nut and the valve.
- If the liquid bubbles out of the threading there is a leak, and the valve needs to be tightened more.
- If there are no bubbles, the seal is good.
- Reset the Gas Monitor in Ops.
- Make a Web-board note; noting the time and date of the alarm and which letter crib is on MAIN and which is on BACKUP.
- Order new Helium 12 pack. Ref SOP-OPS-013
Fig. 1 - (A on MAIN, B on BACKUP; A-line closed)
Fig. 2 - He Crib Main Valve and CGA-580 Nipple
Fig. 3 – Line Valve, Vent and Nipple Holder
Line Valve is Closed
Fig. 4 – Intermediate Vavle (closed).
- CHESS SOP-OPS-013, “Purchasing a helium crib”
Rev. 0 – Initial Document (9/24/10)
Rev. 1 – Update to newer standards. Misc. edits. (06/15/11)
Rev. 2 – Moved step 7 to step 4. Swapped steps 6 and 7. Added step 10. Reworded steps 11, 12. (06/21/11)
Rev. 3 - Added reference for SOP-OPS-013. Updated header to new format (KM 2/17/14)