Well cleaning
United States Patent 2309697
Inventors:
Gunderson, Norris E.
Publication Date:
02/02/1943
View Patent Images:
Export Citation:
Assignee:
LAYNE NORTHERN COMPANY INC
Primary Class:
Other Classes:
166/312, 166/68.500, 166/189, 166/62
International Classes:
E21B37/08; E21B37/00