Hairpin and Concentric Coils are manufactured as complete sets, in groups of coils, with two or three coils within a group, each of the coils within a group will be a different size in the length of the coil and the overhaul span. The cell sections will be determined by the slot dimensions and will all be the same size. The number of groups will be determined by the design of the machine.
The insulated conductor copper strip will be wound continuously around concentric formers to the sizes designated by the technical draft. After shaping the coils will be insulated to the required Insulation Specification. These coils are designed to fit directly into open slots of the stator and normally one coil side per slot.
Hairpin Concentric Coil
Hairpin Coil are designed to be fitted into semi enclosed stator slots, unlike a fully formed Concentric Coil a Hairpin Coil will have one end formed in jigs and with two straight legs unformed, but will have had the stator slot section and the formed end insulated.
The straight unformed legs of each coil will be inserted into the enclosed stator slots by pushing each coil into the slots from either side of the stator frame.
The open unformed end of each coil will be formed to the same shape as the formed end and insulated by the Customer after he has inserted each coil into the stator. An Insulation Kit and Specification comprising of the insulation materials, finishing tapes and varnishes and a full set of Instructions will be supplied to successfully complete the winding.