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公开(公告)号:US2612346A
公开(公告)日:1952-09-30
申请号:US23377351
申请日:1951-06-27
Applicant: STANDARD OIL DEV CO
Inventor: NELSON NORMAN A
IPC: E21B49/10
CPC classification number: E21B49/10
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公开(公告)号:US2665444A
公开(公告)日:1954-01-12
申请号:US18369950
申请日:1950-09-08
Applicant: STANDARD OIL DEV CO
Inventor: NELSON NORMAN A
IPC: E21B33/08
CPC classification number: E21B33/08 , F16L2101/12 , Y10T403/32983
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3.
公开(公告)号:US2646123A
公开(公告)日:1953-07-21
申请号:US20076950
申请日:1950-12-14
Applicant: STANDARD OIL DEV CO
Inventor: NELSON NORMAN A
IPC: E21B33/138
CPC classification number: E21B33/138
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