New insertion device vacuum chambers at the Advanced Photon Source

Six new types of insertion device vacuum chambers have been designed at the Advanced Photon Source (APS). One chamber has been designed for the APS canted undulator beamlines, two for the Canadian Light Source (CLS), and three for BESSY II. For the double canted undulators and CLS, a new extrusion shape with an oval aperture (not elliptical as usual) was developed and extruded. That required a thorough stress analysis and some compromise, which included a small increase of the vacuum chamber wall thickness. The details of the stress analyses and design of the chambers, along with lessons learned, are presented.