Travis, Gerardo, Jordan, Betsy, Tyler, Richard
This morning we proceeded with the manual opening of GV20. Tyler had made a nice support for the input shaft on the gearbox to stabilize it while rotating the handwheel. This worked great, no additional oil leaked out of the gearbox after installation.
We had left the valve soft closed overnight, so we started raising the valve at 10:41:59 Pacific by turning the handwheel counter clockwise, stopping every 50 turns to check the ballnut/shaft collar gap. No issues found.
At turn 370, we tested to see if the handwheel would be driven backwards by the weight of the gate. No backwheeling was present, so we continued raising the valve stopping every 50 turns to check ballnut/ball screw height. At turn 620 we decided to increase the interval between stoppages to 100 turns. After turn 1520, the top of the ball screw was about even with the top of the clutch body. At 1920, there was enough exposed ball screw to install the safety plate and the locking collars. Locking collars were torqued to 140 in-lbs.
We then continued raising the valve 300 turns (2") at a time, adjusting the lock collars at each interval, until the medm screen showed green.
Final turn count: 7167
Final ball screw height, +37.75" from top of clutch body (open position/green on medm) Note: Height stamped on side actuator body read 37 7/8" for the open position.
The interlock pin was then set, and lock collars were moved to top of safety plate, and torqued to 140 in-lbs. The handwheel was left installed on the gearbox with a clamp on it to prevent rotation.
Full set of compiled notes/details will be posted to the DCC with noises/turn counts/timestamps/ball screw heights/etc.
Great write-up and nice work, all.
I notice that there are no comments about concerning noises or "clanking"; pending the handwritten "procedure as traveler" with in-process notes, can we confirm that there were no concerning noises during this manual lift?
Key References related to this effort:
- WGV-20 Escalation https://dcc.ligo.org/T2600441
- Opening Procedure https://dcc.ligo.org/E2600314