Improvement of the stability of the horizontal geometry of LHC cryodipoles when blocking the central support post

This note presents the validation of the improvement of the stability of the horizontal geometry of LHC cryodipoles when preventing the lower flange of the central support post from sliding transversally within the vacuum vessel (i.e. blocking the central support post) [1,2]. The effects of the SM18 cold tests, surface transport and external storage on the horizontal geometry of LHC cryodipoles, with and without the central support blocked, are studied and presented.