IPC Subgroup
E21B 31/2 gripping internally, e.g. fishing spears
Introduced: January 1980
Last revised: January 2006
Full Title
Fishing for or freeing objects in boreholes or wells > Grappling tools, e.g. tongs or grabs > gripping internally, e.g. fishing spears
Classification Context
- Section:
- FIXED CONSTRUCTIONS
- Class:
- EARTH OR ROCK DRILLING; MINING
- Subclass:
- EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS