Bridge joint fabrication and validation for SST-1 PF coil winding pack

• Prototype of bridge type joints fabricated and validated successfully.
• Bridge type joints fabricated and validated on one of the SST-1 PF#3T coil successfully.
• Joint resistance was measured with precision nano volt meter and PXI based data acquisition system.
• Leak tightness of joint box was better than 3 × 10−6 Pa m3 s−1.
• The measured joint resistance of bridge type joint was ∼1.6 nano ohm.

A novel concept of bridge joint for Poloidal field (PF) magnet of SST-1 with damaged winding pack has been realized. This joint has been fabricated on 5th and 6th layers of PF#3T coil winding pack (WP) after validation at 10 kA at liquid helium temperature of 4.2 K in current lead test chamber. The joint resistance of bridge joint was measured ∼1.6 nΩ at flat top DC current of 10 kA. This type of joint could be economically useful for revival of a shorted and damaged WP superconducting PF magnets of Tokamaks. In this paper, details of bridge joint design, fabrication and validations are discussed.