CPC Main Group
E21B 31/00 Fishing for or freeing objects in boreholes or wells
9 direct subcodes
Child Classifications
Navigate with arrow keys, Enter to open
- E21B 31/03 Freeing by flushing
- E21B 31/06 using magnetic means
- E21B 31/08 using junk baskets or the like
- E21B 31/107 using impact means for releasing stuck parts, e.g. jars
- E21B 31/12 Grappling tools, e.g. tongs or grabs