Patent search ap:("BAASH ROSS TOOL CO") AND inv:"FERGUSON THOMAS B" Page 1

1.

发明授权
Flow valve for wells 失效
Title translation: 井的流量阀

公开(公告)号：US2304303A

公开(公告)日：1942-12-08

申请号：US29112039

申请日：1939-08-21

Applicant: BAASH ROSS TOOL CO

Inventor： FERGUSON THOMAS B

IPC: E21B34/12 , E21B43/14

CPC classification number: E21B43/14 , E21B34/12 , Y10T137/86549 , Y10T137/86638 , Y10T137/87804

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