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Finite element results of Low Beta Quadrupole magnets are compared to measurements from three mechanical models. Stress, as measured with internal strain gauges, and radial deflections, as measured with a precision measuring device, are compared to the finite element analysis. The results indicate that measured internal pressures are in agreement with calculations but measured deflections are approximately lower than predicted. The findings will help develop better analyzing and manufacturing techniques to be used on developing the High Gradient Quadrupole magnet.

The recently revived superconducting magnet program at Fermilab is currently focused on the development of high gradient quadrupoles for possible use in the Large Hadron Collider (LHC) interaction regions at CERN. In order to provide input for the new quadrupole design which will operate in superfluid helium, we have tested a Fermilab Tevatron low-/spl beta/ quadrupole cold mass and compared its low temperature performance to a newly assembled heavily instrumented version which was mechanically modified to take advantage of the gain in critical current.

The magnetic design of the LHC interaction region quadrupole by the BNL, FNAL, LBNL collaboration eliminates the manufacturing complication of a graded cable splice in the outer coil and still attains a maximum gradient above 235 T/m. The mechanical design includes strong preloaded collars, shims to adjust the fit between components when warm, contact between the collar and iron when cold for better coil support, and a closed iron to reduce harmonics. This paper summarizes mechanical finite element results for assembly, cooldown to 1.8 K, and excitation to maximum gradient.

A collaboration of Fermilab, Lawrence Berkeley National Laboratory and Brookhaven National Laboratory is engaged in the design of a high gradient quadrupole suitable for use in the LHC interaction regions. The cold iron design incorporates a two-layer, cos(2/spl theta/) coil geometry with a 70 mm aperture operating in superfluid helium. This paper summarizes the progress on a magnetic, mechanical and thermal design that meets the requirements of maximum gradient above 250 T/m, high field quality and provision for adequate cooling in a high radiation environment.

In this study, a finite element model is used to predict the vacuum vessel’s response to loads resulting from its own self-weight and shipping and handling. Structural members of the cold mass support system must behave elastically during assembly and transport of the magnets so that alignment with respect to an external reference is reproducible. This paper includes deflection and stress analyses of the vacuum vessel for the SSC 50 mm collider dipole cryostats. In addition, material selection and stress relieving techniques are discussed. Several methods of local structural reinforcement were analyzed prior to the selection of the current design. The results from these analyses are given for comparison.