A flange isolation kit has three dielectric barriers, and the sleeve is the one that goes through the hole. The central gasket isolates the flange faces. The G10 insulation sleeve slides over each stud bolt and fills the annular gap between the bolt and the flange bore — without it, the bolt shank touches the flange hole and the cathodic protection circuit grounds through the fastener. Kaxite manufactures NEMA LI-1 G-10 sleeves from epoxy-impregnated woven glass tube: 1/32″ standard wall, 8–800 mm diameter range, ≥400 V/mil sleeve-grade dielectric strength, 130–150°C continuous. Standard sizes ship in 5–10 days; custom diameters cut from 500 pieces per size.
