DC

Donald B. Caldwell

3M: 1 patents #7,233 of 11,543Top 65%
Overall (All Time): #1,306,257 of 4,157,543Top 35%
4
Patents All Time

Issued Patents All Time

Showing 1–4 of 4 patents

Patent #TitleCo-InventorsDate
4711299 Apparatus and methods for pumping solids and undesirable liquids from a well bore Robert J. Spring 1987-12-08
4621693 Apparatus and methods for pumping solids and undesirable liquids from a well bore Robert J. Spring 1986-11-11
4478285 Method and apparatus for removal of downhole well debris 1984-10-23
4223073 High-temperature damping composite Thomas F. Gardeski 1980-09-16