Patent assignee · COMPANY

Preussag Aktiengesellschaft

23Patents
0Active
23Granted
33Portfolio score

Filing activity: Jun 21, 1974 → May 29, 1992

Most-cited patents

PatentTitleAreaCited byStatus
US4947944A Device for steering a drilling tool and/or drill string Fixed Constructions 70 Expired
US5182731A Well bore data transmission apparatus Fixed Constructions 61 Expired
US4442908A Tool for drilling curved sections of well holes Fixed Constructions 49 Expired
US5246070A Piping for the completion of a groundwater monitoring site Mechanical Engineering; Lighting; Heating 17 Expired
US3939391A Apparatus for charging a hermetically sealed electrical energy source Electricity 13 Expired
US4386473A Recovery of sediments from the bottom of the sea Fixed Constructions 12 Expired
US4316386A Fluid pressure measuring apparatus for incorporation into a pipeline rising from a well Fixed Constructions 11 Expired
US4153357A Underwater camera Physics 11 Expired
US5224389A Method and apparatus for taking samples from a groundwater monitoring site Physics 10 Expired
US4688831A Threaded or push-type coupling Fixed Constructions 10 Expired
US4184758A Deep sea underwater camera Physics 7 Expired
US5154538A Method and apparatus for removing a liquid phase floating on a surface of groundwater Performing Operations; Transporting 7 Expired
US4035816A Housing assembly for an underwater camera with a flash device Physics 6 Expired
US4168673A Floating island for extracting or processing gas Performing Operations; Transporting 6 Expired
US3996678A Free-fall grab Fixed Constructions 5 Expired
US3960511A Zone melting process Chemistry; Metallurgy 4 Expired
US3935058A Zone melting process Emerging Cross-Sectional Technologies 4 Expired
US4293265A Hydraulically operated hoisting apparatus for a ship for picking floating objects up out of the sea Performing Operations; Transporting 3 Expired
US4398361A Recovery of sediments from the bottom of the sea by suspended suction pipe Fixed Constructions 3 Expired
US4580049A Probe for locating mineral deposits Physics 2 Expired
US4652055A Device for collecting manganese nodules on the ocean floor Fixed Constructions 1 Expired
US4160623A Deep well pump Mechanical Engineering; Lighting; Heating 0 Expired
US4158963A Process for determining the location and/or extent of rock cavities Fixed Constructions 0 Expired

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