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公开(公告)号:US2521332A
公开(公告)日:1950-09-05
申请号:US2287848
申请日:1948-04-23
Applicant: STANDARD OIL DEV CO
Inventor: BLOOD ROBERT H , WILLIAM SEWELL BEN
CPC classification number: E21B49/083 , E21B43/082
公开(公告)号:US2521332A
公开(公告)日:1950-09-05
申请号:US2287848
申请日:1948-04-23
Applicant: STANDARD OIL DEV CO
Inventor: BLOOD ROBERT H , WILLIAM SEWELL BEN
CPC classification number: E21B49/083 , E21B43/082