Inventor · Hermannsburg, DE

Friedhelm Makohl

14Patents
10h-index
20Co-inventors
72Inventor score

Filing activity: Aug 1, 1983 → Jun 16, 2003

Most-cited inventions

PatentTitleAreaCited byStatus
US6196336A Method and apparatus for drilling boreholes in earth formations (drilling liner systems) Fixed Constructions 204 Expired
US6419033B1 Apparatus and method for simultaneous drilling and casing wellbores Fixed Constructions 188 Expired
US6850068B2 Formation resistivity measurement sensor contained onboard a drill bit (resistivity in bit) Emerging Cross-Sectional Technologies 74 Expired
US5738173A Universal pipe and tubing injection apparatus and method Fixed Constructions 42 Expired
US5890534A Variable injector Fixed Constructions 34 Expired
US5845708A Coiled tubing apparatus Fixed Constructions 30 Expired
US5823267A Universal pipe and tubing injection apparatus and method Fixed Constructions 17 Expired
US4773489A Core drilling tool for boreholes in rock Fixed Constructions 17 Expired
US6032744A Universal pipe and tubing injection apparatus and method Fixed Constructions 16 Expired
US5875850A Universal pipe and tubing injection apparatus and method Fixed Constructions 15 Expired
US6390201B1 Method of creating a downhole sealing and hanging device Fixed Constructions 9 Expired
US7234546B2 Drilling and cementing casing system Fixed Constructions 9 Expired
US5205364A Process and drilling equipment for sinking a well in underground rock formations Fixed Constructions 8 Expired
US4485880A Direct drive for deep-well drilling Emerging Cross-Sectional Technologies 7 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.