Mechanical Design of a Heavy Ion RFQ

The mechanical design and construction of a 199.3 MHz heavy ion RFQ for charge states q/A as low as 0.14 is described. The vane supports and positioning adjustments are signifcant features of this design. They provide the capability of achieving the precision vane alignment required. The maximum difference between calculated and measured apertures between the vanes is 0.0035 inches, and the average difference is 0.0010 inches. Various important aspects of the design and construction including material selection and plating, RF joints, thermal loading and vacuum system are described. Assembly techniques, methods of mechanical measurement, alignment and structure stability are discussed in detail.