Manufacturing process for gradient coil sub-assemblies

A method of manufacturing a gradient coil sub-assembly, comprising:

• a) laminating a first punched sheet metal conductive saddle coil portion and a second punched sheet metal conductive saddle coil portion together by bonding the first and second punched sheet metal conductive saddle coil portions on opposing sides of a B-stage material insulation layer;
• and
• b) electrically connecting the first punched sheet metal conductive saddle coil portion to the second punched sheet metal conductive saddle coil portion in parallel so that the first and second conductive saddle coil portions act together as one saddle coil,
• wherein, the gradient coil sub-assembly comprises:
• a first coil layer comprising the first punched sheet metal conductive saddle coil portion which has a higher incidence of burrs, left by a respective punching process, on one face than an opposing face of the first coil layer,
• a second coil layer comprising the second punched sheet metal conductive saddle coil portion which has a higher incidence of burrs, left by a respective punching process, on one face than an opposing face of the second coil layer,
• the B-stage material insulation layer is sandwiched between the first and second coil layers, with the first punched sheet metal conductive saddle coil portion bonded to a first side of the B-stage material insulation layer and the second punched sheet metal conductive saddle coil portion bonded to a second, opposite, side of the B-stage material insulation layer and the one face of each of the first and second punched sheet metal conductive saddle coil portions having the higher incidence of burrs are facing and bonded to the B-stage material insulation layer, such that the B-stage material insulation layer and burrs are located in a region of minimized electric field strength when the the gradient coil sub-assembly is used in an MRI machine helping minimize partial discharge.