Parametric Analysis of Forces and Stresses in Superconducting Quadrupole Sector Windings

This paper presents a review of the existing analytical approximations of the magnetic field of a sector winding quadrupole, evaluating to which extent these formulae are usable as a first estimation of the resultants of the electromagnetic forces and related mechanical stresses produced. The distribution of the forces has been investigated to better understand the stress provided to the structure containing the windings and the compression effect induced on the coil mid plane. Therefore, the study has been carried out setting the magnet current at its critical value, analyzing forces and stresses as functions of the geometrical layout and of the magnetic gradient as well. In the last part the effect of an iron yoke on the magnetic field and forces is presented.