v1.0   2015April 02

Plan for HAM6 Vent, April 2-8, 2015

Approved work to be done:

1. OM1 mirror replacement.
2. Install a 90:10 BS in OMCR.
3. Lubricate beam diverter with Krytox LVP  (verbal approval by D. Coyne, 4/1/2015, for limited use)
4. QPD cables strain relief.
5. Measure HAM6 power budget.

DCC Vent Documents referenced in this plan:

• E1201035-v17, "aLIGO Chamber Entry & Exit Procedures"  https://dcc.ligo.org/LIGO-E1201035
• M1100039, "Hanford Checklist - HAM Door Removal"  https://dcc.ligo.org/LIGO-M1100039
• M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown"  https://dcc.ligo.org/LIGO-M1300464

Additional Documentation:

• The ECR approving the use of Krytox LVP is E1400353.
• The Beam Diverter assmbly is described in E1100686-v3 .

The HAM6 door to be removed is the "East" door.

Schedule

Thursday, April 2, 2015

1. 1st cleaning of HAM6 area [technical cleaning crew]
2. Move Clean Room (CR) into position for HAM6, turn on fans, and verify fans are working [Bubba, Gerardo]
3. Set up dust monitor and verify it is working. [Jeff B.]

Monday, April 6, 2015

1. 2nd cleaning of HAM6 [technical cleaning crew]
2. Verify and confirm CR (clean room) supplies are in place (gowns, change room, ...). [Jeff B. or Betsy]
3. Verify safe.snap files. [CDS: Dave Barker]
4. Review and follow E1201035-v17, "aLIGO Chamber Entry & Exit Procedures" checklist as annotated by Calum and Dennis for abbreviated entry. https://dcc.ligo.org/LIGO-E1201035
5. Review and follow M1100039, "Hanford Checklist - HAM Door Removal" https://dcc.ligo.org/LIGO-M1100039 . [Betsy is keeper of the list]

Tuesday, April 7, 2015

1. Vacuum crew: Follow M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown". https://dcc.ligo.org/LIGO-M1300464 . Note on Fast Shutter: De-energize HAM6 Fast Shutter High Voltage (HV) and Low Voltage (LV) as per the following steps:
   1.  Set HV switch on fron of panel on D1400078 to “disable”.
      
   2.  Shut off Kepco power supply (LV Power Supply Room) serving fast shutter.
      
   3.  Back at D1400078 set rocker switch to off position on back of D1400078.
2. CDS controls crew check: The controls system needs to be up and running during the HAM6 work, so make sure that normal Tuesday maintenance activity on CDS doesn't interfere with the vent activities.
3. Verify Purge Air on.
4. Wipe down of door. [Technical Cleaners]
5. Lock HEPI, apply HEPI dust covers
6. Transition to "Laser Safe" (IR, TSC 10um); End Station green lasers to remain on as closed gate valves block beams into LVEA [clarify with P. King]
7. Close Gate Valves to Arm Cavities
8. Start vent on HAM6, estimate 1-2 hours duration. [Kyle or Bubba]
9. Dust Monitors - verify operation and take readings for before and after entry. [Jeff B.]
10. Remove door, following M1100039
11. In-chamber work (ISI lockers access through East door ) [Koji A. is team captain]:

In-chamber Work Plan:

Preparation

- Open East door of HAM6
- ISI locking
- Align the beam on the AS_C QPD
- Align the beam on the OMC QPDs
- Confirm the beam is on the WFS QPDs

OM1 mirror replacement

- OM1 mirror replacement

New optic
Usual CLASS B Allen wrenches
First contact removal kit: UHV N2 & ionizing blow kit
If removal of the optics does not work:
=> CG: Tip Tilt Spare
S/N 28 is in a bag on the bottom shelf of rack in the Optics Lab, if needed.

- Align the spots on OMC QPDs/WFS QPDs with OM1 and OM2
- Check if the BOSEM values are OK or not.

If not, we need to retune the BOSEM positions (debiasing)
A hex box wrench for BOSEM adjustment

- Check or align the AS_AIR path
- Align AS_C QPD

At LLO, pitching up of the OM1 suspension was observed. This case, the balancing screws needs to be replaced. Therefore it’s better to prepare
CLASS A #8-32 set/cap screws/nuts

Inserting a 90:10 BS in OMCR

- Check if the small mirrors at the OMC REFL have no clipping
- Insert the 90:10 BS in the path.

The optic on the mount
CG: 2” Mount for new BS & post
We definitely do not have 2" Mirror Mounts. We have plenty of 2" lens holders. We have varying posts, so we should confirm what works with lens holder.
=> This is OK

As Lisa states, we have a bag of these (E1500009) in the Optics Lab. They still need to be cleaned.

ISC Dog Clamps:
There are bags of both type of ISC-specific dog clamps on the shelf in Optics Lab.

- Dump the reflection with the beam dump

The beam dump on the mount
CG: V-Holder Beam Dump Assembly
We have these parts in the Optics Lab.

- Align the OMC REFL AIR path to recover the alignment
- Align the OMC REFL QPDs

QPD cable strain relief

- Attach QPD cable strain relief to AS_C/OMCR_A/OMCR_B QPDs

3x D1101910
3x D1101911
3x SHCS 1/4-20 x1/2” non plated
6x SHCS 8-32 x 1/2” non plated
CG: I have both Peek parts & we also must have c&B-ed the hardware for them, because two bags of bolts were with the parts.
I have put all (4) bags in the H1 Spare QPD tote under the optics Table.

Lubrication of the beam diverter

- Apply Krytox on BD
Krytox: Permission received from Dennis Coyne, application tips from Matt H./Rich A. => Some information will be provided in a couple of days)

Counterweight for Beam Diverter

Need to see what type of screw can be used for the hole on the Beam Diverter and see what we have. We should be OK.

HAM6 Power Budget

- Measure optical power (OMC Unlocked) OM1 incident

OM1 transmission
OM1 BS incident
OM1 BS transmission vs AS_C sum OM1 BS reflection
AS_AIR (window transmission) OM2 incident
OM3 incident
OMC incident
OMC Reflection (Unlocked)
OMCR BS90/10 incident
OMCR BS90/10 reflection
OMCR BS90/10 transission
OMCR BS50/50 transission
OMCR BS50/50 reflection
OMCR QPDA incident (vs OMCR QPDA digital reading) OMCR QPDB incident (vs OMCR QPDB digital reading) OMCR AIR (window transmission)

- Lock OMC

(OMC incident)
OMC transmission (DCPDA/DCPDB analog/digital reading)
OMC REFL
OMC leakage trans?
For locking the OMC, we need to turn stop the purge air, and probably stop/lower the HEPA fans.

Exit procedure

- Take photos of the table => Send them to Eddie - Ground loop check
- ISI unlock

The following may take place on Wednesday.
- Hang door
- OM1 TF check
- Prepare for Door closing and Pumpdown

Wednesday, April 8, 2015

1. After completion of in-chamber work, obtain approval and signatures for volume closure, LHO (see E1400474-v1). [Vern]
2. Obtain sign off signatures for chamber closure.
3. Verify ISI unlocked.
4. Notify door crew to hang door.
5. Assess status of suspension, TF measurements. [Betsy or Jeff K.]
6. Verify readiness to pump down, follow M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown". Re-confirm that all high voltages are off.
7. Notify Vacuum crew of readiness to start pumps.
8. Restore HEPI
9. Return to Laser Hazard Condition
   

The transitions to and from "Laser Safe" need to be reviewed with Peter King.  The is the possibility of additional transition cycles during the in-chamber time period.  There may be independent cycling of the CO2 (10um) lasers. These need to be worked out in more detail.

The pump down is at the time and discretion of the Vacuum crew.

Reminder: File work permits for all door openings and closings. [Vacuum Crew]

For Reference:

ISC Prep Work (Corey's List)

Strain Relief Assy:
I have both Peek parts & we also must have c&B-ed the hardware for them, because two bags of bolts were with the parts.  I have put all (4) bags in the H1 Spare QPD tote under the optics Table.

Krytox
I have a tube of it in my desk (center drawer).  John was asking about waivers from Dennis for this (so we should look to see if those are around; perhaps in some Heintze documentation?).

Tip Tilt Spare
S/N 28 is in a bag on the bottom shelf of rack in the Optics Lab, if needed.

2" Mount for new BS & post
We definitely do not have 2" Mirror Mounts.  We have plenty of 2" lens holders.  We have varying posts, so we should confirm what works with lens holder.

V-Holder Beam Dump Assembly
We have these parts in the Optics Lab.
90% BS
As Lisa states, we have a bag of these (E1500009) in the Optics Lab.  One still needs to be cleaned for next week.

ISC Dog Clamps
There are bags of both type of ISC-specific dog clamps on the shelf in Optics Lab.

Counterweight for Beam Diverter
I need to see what type of screw can be used for the hole on the Beam Diverter and see what we have.  We should be OK.

OM1 Mirror
An OM1 mirror (E1100056) should be found and cleaned by Corey.