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公开(公告)号:US1753074A
公开(公告)日:1930-04-01
申请号:US30656528
申请日:1928-09-17
Applicant: BATAAFSCHE PETROLEUM
Inventor: KEULEN GODEFRIDUS HENDRIKUS CL
IPC: E21B31/20
CPC classification number: E21B31/20
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公开(公告)号:US1830214A
公开(公告)日:1931-11-03
申请号:US34799929
申请日:1929-03-18
Applicant: BATAAFSCHE PETROLEUM
Inventor: KEULEN GODEFRIDUS HENDRIKUS CL
IPC: E21B33/06
CPC classification number: E21B33/061 , Y10T279/17085
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