Patent assignee · US · COMPANY

Otis Engineering Corporation

472Patents
2Active
472Granted
44Portfolio score

Filing activity: Jul 12, 1972 → Aug 28, 1992

Most-cited patents

PatentTitleAreaCited byStatus
US4425965A Safety system for submersible pump Fixed Constructions 140 Expired
US5188182A System containing expendible isolation valve with frangible sealing member, seat arrangement and method for use Fixed Constructions 134 Expired
US4288082A Well sealing system Mechanical Engineering; Lighting; Heating 132 Expired
US5172717A Well control system Emerging Cross-Sectional Technologies 131 Expired
US4919204A Apparatus and methods for cleaning a well Fixed Constructions 128 Expired
US4636934A Well valve control system Emerging Cross-Sectional Technologies 120 Expired
US4396061A Locking mandrel for a well flow conductor Fixed Constructions 109 Expired
US5176164A Flow control valve system Emerging Cross-Sectional Technologies 109 Expired
US4473245A Pipe joint Mechanical Engineering; Lighting; Heating 105 Expired
US4436150A Bridge plug Fixed Constructions 97 Expired
US5211241A Variable flow sliding sleeve valve and positioning shifting tool therefor Fixed Constructions 97 Expired
US4399871A Chemical injection valve with openable bypass Emerging Cross-Sectional Technologies 96 Expired
US5004049A Low profile dual screen prepack Fixed Constructions 93 Expired
US5293551A Monitor and control circuit for electric surface controlled subsurface valve system Electricity 90 Expired
US5094340A Gripper blocks for reeled tubing injectors Performing Operations; Transporting 89 Expired
US5226483A Safety valve landing nipple and method Fixed Constructions 86 Expired
US4930573A Dual hydraulic set packer Fixed Constructions 83 Expired
US4981173A Electric surface controlled subsurface valve system Fixed Constructions 80 Expired
US4633954A Well production controller system Emerging Cross-Sectional Technologies 79 Expired
US4655291A Injector for coupled pipe Fixed Constructions 78 Expired
US5107927A Orienting tool for slant/horizontal completions Fixed Constructions 78 Expired
US4753444A Seal and seal assembly for well tools Emerging Cross-Sectional Technologies 77 Expired
US5174379A Gravel packing and perforating a well in a single trip Fixed Constructions 76 Expired
US4248302A Method and apparatus for recovering viscous petroleum from tar sand Fixed Constructions 75 Expired
US4624315A Subsurface safety valve with lock-open system Fixed Constructions 73 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.