DIFF Subgroup
E21B 15/02 specially adapted for underwater drilling (E21B15/04 takes precedence)
Introduced: September 1968
Title
Titles differ between systems:
IPC: specially adapted for underwater drilling
CPC: specially adapted for underwater drilling (E21B15/04 takes precedence)
Full Title
Full titles differ between systems:
IPC:
Supports for the drilling machine, e.g. derricks or masts > specially adapted for underwater drilling
CPC:
Supports for the drilling machine, e.g. derricks or masts > specially adapted for underwater drilling (E21B15/04 takes precedence)
No child classifications to compare. This is a leaf node in both IPC and CPC.