In-Situ Bake-Out Scheme for Thin-Walled Chambers at Extremely High Vacuum of HIAF

摘要

To keep eddy currents at a tolerable level,thin-walled stainless steel vacuum chambers with wall thickness of 0.3 mm are needed in HAIF BRing magnets.To withstand atmospheric pressure the thin-walled vacuum chambers are supported by ribs which is parallel to the magnetic field lines.In order to obtain the extremely high vacuum(XHV),the chambers have to be bakeable to 220300℃.According to a given design requirement,the in-situ bake-out scheme of XHV thin-walled chambers with a narrow magnetic gap was studied,where the temperature of surrounding magnetic elements is strictly controlled to below 80℃.