Inventor · disambiguated record
David A. Hejl
Also filed as: HEJL DAVID · HEJL DAVID A
8 granted patents·209 citations·filing 2001–2021
87Inventor score
Technology areasE21B
Files withHALLIBURTON ENERGY SERV INC5BAKER HUGHES OILFIELD OPERATIONS LLC1HEJL DAVID A1PARAMHANS SHIVA1
Top patents by PatentIndex Score
8 records- 0181US6516882B2Apparatus and method for gravel packing an interval of a wellboreHALLIBURTON ENERGY SERV INC·Filed 2001·Granted Feb 11, 2003·62 cites·36 claims
- 0277US7252153B2Bi-directional fluid loss device and methodHALLIBURTON ENERGY SERV INC·Filed 2005·Granted Aug 7, 2007·25 cites·19 claims
- 0376US7243724B2Apparatus and method for treating an interval of a wellboreHALLIBURTON ENERGY SERV INC·Filed 2004·Granted Jul 17, 2007·40 cites·42 claims
- 0476US6789624B2Apparatus and method for gravel packing an interval of a wellboreHALLIBURTON ENERGY SERV INC·Filed 2002·Granted Sep 14, 2004·44 cites·28 claims
- 0569US6814139B2Gravel packing apparatus having an integrated joint connection and method for use of sameHALLIBURTON ENERGY SERV INC·Filed 2002·Granted Nov 9, 2004·37 cites·37 claims
- 0647US9790789B2Apparatus and method for obtaining formation fluid samplesHEJL DAVID A·Filed 2012·Granted Oct 17, 2017·1 cites·20 claims
- 0745US11629592B1Extendable downhole tool and related systems, apparatus, and methodsBAKER HUGHES OILFIELD OPERATIONS LLC·Filed 2021·Granted Apr 18, 2023·0 cites·20 claims
- 0827US10316657B2Extendable probe and formation testing tool and methodPARAMHANS SHIVA·Filed 2015·Granted Jun 11, 2019·0 cites·11 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →