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Download BNMRfit istallation script Download BNMRfit Download BNMRminfit	Getting out a sample from $\beta$ NMR cryostat Figure 6.2: Vacuum system If the load lock is under vacuum, vent it through SVV5 (see figure above) note there is a manual valve in line with this automatic valve. Remove the blankoff on the top of the lock by undoing the three bolts with the allan key located on the side of the lock. Keeping the rubber o-ring in place, mount the clean end of the manipulator into the vacuum lock and seal it using the three screws and the allan key. Do not get the manipulator's clean end dirty by touching it with your bare hand for example. Rough out the lock: Go To the Control Room and Get the operator to open up the EPICS page shown above Make sure the vent valve SVV5 is closed Turn on the roughing pump if it is off. (the round black circle BNMRBP5 above should be green) Note the Fuji dry roughing pumps are often switched off due to their short lifetimes If the roughing pump is working the convectron gauge BNMRCG5 should go down to some low value like 50 mT - that's T for Torr Open the valves to the lock: PV5, RVX6 and RV5 You can watch it rough down on the convectron gauges CG6A and CG5D Rough out the backside of the sliding seal: Ensure the KF25 flexible pumping line is connected to the flange on the side of the manipulator Close RV5 Note typically the lock pressure comes up when you isolate it due to outgassing this can be seen on CG5D Open RV7 Watch it pump out on convectron CG6A Spin Up the Turbo Pump BNMRTP6 - the yellow circle above You need to back it with the roughing pump first, close VX6 then open BV6 When it is safe, open the inlet side of TP6 using GV6 Pump out the lock and the backside of the sliding seal: Let it pump for a while, then close RV7 and start pumping on the lock (open RV5) Pump the lock for  15mins The gauge CG5D will quickly bottom out, but After a while you can turn on the ion gauge IG6 at the turbo and watch it come down to a few microTorr Prepare to open the gate valve: Turn off the ion gauge IG6 to protect it Close RV5, isolating the lock Then QUICKLY open RV7 to pump on the "differential space" at the back of the sliding seal If you are too slow the TP will trip off and you have to turn it back on. Note when the manipulator is going into the UHV space, you must pump continuously on the differential space with the turbo Let it pump for a minute or two Open the gate valve (SLV5) now the lock is open and the UHV is spoiled (not badly if you have followed the above) Go to the platform push the manipulator down, opening the hatch if you haven't already Using the motor and the side-to-side play of the bellows on the lock position the manipulator directly over the threaded hole in the sample holder Unscrew the sample: note this is a reverse thread, so you turn as if you were taking it out (pressenig gently to engage the threads). This is Counterclockwise! Once the reverse thread is fully engaged, the outer normal threads will begin to pull out. Continue turning the same way until the holder is free Retract the manipulator (with holder attached) into the lock all the way ENSURE the holder is up by using the brass rod to keep the manipulator handle at the necessary height Once this is done, close the gate valve from the control room SLV5 Vent the lock Remove sample and manipulator (without touching the clean end) Blank off the lock to keep it clean Turn off the roughing pump if you are going to be a while.
	Page last modified: 07/23/09 02:45 by Andrew MacFarlane.