-
公开(公告)号:US1935078A
公开(公告)日:1933-11-14
申请号:US21654427
申请日:1927-08-31
Applicant: STANDARD OIL CO CALIFORNIA
Inventor: CAVINS OMAR A
IPC: E21B25/16
CPC classification number: E21B25/16
-
公开(公告)号:US2018946A
公开(公告)日:1935-10-29
申请号:US63473332
申请日:1932-09-24
Applicant: STANDARD OIL CO CALIFORNIA
Inventor: CAVINS OMAR A
IPC: H01H29/20
CPC classification number: H01H29/20
-
公开(公告)号:US1962634A
公开(公告)日:1934-06-12
申请号:US21654527
申请日:1927-08-31
Applicant: STANDARD OIL CO CALIFORNIA
Inventor: CAVINS OMAR A
IPC: E21B47/022
CPC classification number: E21B47/022
-
-