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The so called nautilus is a winding form in the shape of a double helical spiral onto which a stiff conductor is wound. The conductor is thus bent to a radius smaller than the desired local curvature. When the conductor is allowed to relax from the nautilus form, the required radius of curvature is achieved everywhere. The stiffness in the axial direction is small and compression of the wound coil to a disc is easy. The coil is tightened to a compact disc by pulling the outer tails.

The development of a high resolution high-field 1 GHz NMR spectrometer has been undertaken by Battelle Pacific Northwest Laboratories (BPNL). In preparation for the design of the superconducting magnet for that instrument, BPNL sponsored a program to measure the properties at high field (up to 23.5 T) and low temperature (1.8 K) of a number of commercially available superconductors. Lengths of these conductors were obtained and tested as short samples and in small coils. The critical current densities, index values and strain dependence of these properties were characterized. The potential applications of these conductors in construction of a 1 GHz NMR magnet are discussed.

Bitter magnets offer some advantages to the construction of high temperature superconducting magnets. The superconductor is manufactured in the required shape. This avoids the need to develop ductile materials. This method can be utilized for manufacturing solenoidal, toroidal, saddle, and other types of magnets. The issues facing this type of magnet construction will be discussed, including quench protection, materials compatibility, stability, and cooling. The technique is especially suited to resolve some of the compatibility problems between the brittle superconductor and the structure. Novel methods to improve the compatibility between the superconductor and the structure will be presented. The results of FEM modelling and preliminary testing of the superconductor composite will be shown.

A 45 T Hybrid magnet is to be installed at the National High Magnetic Field Laboratory at Tallahassee. The superconducting background field magnet of this system consists of three coils, two of niobium-tin conductor and one of niobium-titanium. This paper describes the design and construction of the niobium-titanium section. In the design, three issues of principal importance were considered: stability and dissipation under pulsed and steady state conditions; the stressing of the conduit, and the consequences of quenching. The details of construction have centered around the winding and assembly of the pancake coils and the preparation of the joints. The construction of the coil is part of a collaborative program between MIT and FSU.

The new National High Magnetic Field Laboratory (NHMFL) at Tallahassee, Florida is committed to putting into operation in 1995 a 45-T Hybrid Magnet System to support research in steady, high magnetic fields. This facility will be accessible by qualified users world-wide on the basis of proposal and review. The more prominent components of this system will be a 24-MW resistive insert and a 120-MJ superconducting outsert. But successful achievement of the performance goals for the 45-T Hybrid System will depend on a number of unique, state-of-the-art subsystems and components. This paper describes the requirements and specifications on the individual subsystems and components in the context of the overall performance goals and reviews the plan for putting the whole together.

A simulation code for worst-case parameter estimation of the quench properties in multisection superconducting coils is introduced. It is a design tool in the joint project between the Massachusetts Institute of Technology and Japan's Kobe Steel Ltd for the development of a 12-coil 17.6-T 750-MHz nuclear magnetic resonance system. Its application for testing the magnet's five outer niobium titanium solenoids are also discussed.

A hybrid magnet system is slated to be operational at the National High Magnetic Field Laboratory at Florida State University in 1995. Its design, which revolves around the use of cable-in-conductors, involves a water-cooled resistive insert and a superconducting outsert made of NbTi and Nb3Sn which will be cooled by superfluid helium. The structure, including the 33-mm bore containing the inserts, will provide a 45-T magnetic field with the superconducting part contributing more than 14 T.

The Hybrid III superconducting magnet (SCM) was constructed in 1991 to supplement the 31-T Hybrid II facility magnet at the Francis Bitter National Magnet Laboratory. With a quasi-adiabatic designed coil, the SCM induced a total central field of 33.5 T during tests while submerged in liquid helium at 1.65 K. It also generated a critical current of 2200 A. Although tests have demonstrated that it may achieve an operating temperature of 1.7 K and a critical current of 2230 A, work is ongoing to obtain a central field of 35 T.

Focuses on the nautilus winding method for winding disc coil of stiff conductor. Principles behind the nautilus winding method; Construction of the nautilus; Conclusions.