CPC Subgroup
E21B 33/134 Bridging plugs
Full Title
Sealing or packing boreholes or wells > in the borehole > Methods or devices for cementing, for plugging holes, crevices or the like > Bridging plugs
E21B 33/134 Sealing or packing boreholes or wells > in the borehole > Methods or devices for cementing, for plugging holes, crevices or the like > Bridging plugs