After a day of respite, the magnet was back under the angle grinder this morning and quick work was made of the 20K radiation shield (aluminium) and liquid helium vessel casing (stainless steel again).
|What lies behind door number 5?|
Having cut through the liquid helium vessel, we can now see the aluminium baffle surrounding the magnet itself. This baffle protects the magnet from fluctuations during helium fills (as well as serving as an additional radiation shield). In the image above we can also see the quench resistors that protect the windings from the huge currents that reside therein in the event of quench. These resistors are arranged in a double row on top of the baffle and run behind the bore tube and around the other side.
In the images to the right, we can see the transfer lines that direct the flow of liquid helium during a fill (front line) and measure the helium level when required (back line).
The aluminium baffle should be the last significant barrier to the windings - once that's down, we'll be down to a Stanley knife!