DIFF Subgroup
E21B 29/002 Full Title
Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
Of 2 combined children, 0 exist in both systems.
2 codes are CPC-only extensions.