|
US3545313A
|
|
Combined grapple and back-up tong
|
|
US3097552A
|
|
Pipe tongs
|
|
US3099323A
|
|
Transfer platform for drill pipe elevators
|
|
US2871743A
|
|
Hydraulic pipe tonging device
|
|
US2829617A
|
|
Power slips with warning signal means
|
|
US2675105A
|
|
Cam operated clutch for catheads
|
|
US2475899A
|
|
Antifouling device for catheads
|
|
US2522377A
|
|
Clutch and brake mechanism for cathead assembly
|
|
US2540451A
|
|
Pipe aligning device
|
|
US2594446A
|
|
Slip lifter lock
|
|
US2340597A
|
|
Rotary slip lifter
|
|
US2351343A
|
|
Oil saver
|
|
US2300122A
|
|
Cathead and spinning drum assembly
|
|
US1505567A
|
|
Swivel wrench
|
|
US1405223A
|
|
Casing spider and slips
|
|
US1442669A
|
|
Drilling tool
|
|
US698290A
|
|
Feed-water heater.
|
|
US699535A
|
|
Drilling-machine.
|
