Feasibility to avoid an electrical insulation in superconducting (sc) windings, i.e., to "short-circuit" their turns, is attractive from several points of view. Firstly, it may be beneficial from the standpoint of average current density increase of a sc winding. Secondly, it improves the winding's mechanical properties. Last but not least is that for a sc winding with "short-circuited" turns very fast quench propagation should be typical, and hence stored energy should more or less uniformly dissipate over the winding volume, while an overvoltage is impossible "by definition". Most likely "short-circuited" sc windings can be used only for DC applications. The main problem is to obtain acceptable times of charging. Characteristic time of charging is evaluated by the ratio of the winding's inductance to the integrated inter-turn (transverse) resistance. Therefore, a proper increase of the latter is one of the ways to go to acceptable charging times. Test results of several "short-circuited" windings are described. Some methods to increase the inter-turn resistance are discussed and tested. A model of quench propagation in "short-circuited" windings is developed, and relevant computational results are presented.
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