Second generation "Flat-Fish" vacuum chamber for an ISR intersection

The picture shows the part of the "Flat-Fish" chamber covering one side of the beam intersection region. The other side is covered by an equal part and both are welded toghether at their small end. The two shells of each part were hydroformed from 0.15 mm thick inconel 718 sheet (with end parts in inconel 600 for easier manual welding to the arms) and welded toghether with two strips which were attached by means of stainless steel strings to the Split Field Magnet poles in order to take the atmospheric pressure forces. This was the thinnest vacuum chamber made for the ISR. Inconel material was chosen for its high elastic modulus and strenght at chamber bake-out temperature.