Videos of the Borexino nylon vessels installation (Jan – May, 2004).
Here are some time-lapse videos of the whole operation, as seen by Borexino’s internal CCD photo-cameras, mounted on the Stainless Steel Sphere (inside dedicated sealed chambers, with special glass window). Each of the different video below corresponds to a different camera, which is located on a different position on the SSS, so that you can watch from different angles how this particularly delicate and critical operation had progressed. The two concentric nylon vessels had to be installed, attached to the special support system, connected to the pipes for fluid handling, etc, and eventually slowly inflated with ultra-pure, humidified nitrogen gas. In the video you can also see our personnel at work, which will give you a sense of the dimension of the SSS and of the nylon vessels (see in particular video from camera #4, #5 and #7).
During this operation the thin, large and delicate nylon vessels could have easily got punched and/or ripped off, rendering them unusable. Which would have been quite a disaster. Not only the special vessels had to be custom built, but – like everything in Borexino – that had to be done in a clean room, using carefully selected materials, tools, and procedures to guarantee the required radio-purity. It was a rather complex and lengthy task. Beside the costs, a failure forcing us to rebuild a new pair of vessels would have caused a substantial delay in our schedule. Fortunately everything went as planned, and at the end you can see the two concentric spherical vessels installed and inflated, ready for the following steps (the water filling of the SSS and nylon vessels, then of the Water Tank, and eventually the substitution of the water with the buffer and scintillator solutions in the SSS and nylon vessels, which concluded the detector construction).
Video: Borexino internal nylon vessels installation