The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 08, 1982
Filed:
Jul. 03, 1980
Applicant:
Inventor:
Neil W Herst, Houston, TX (US);
Assignee:
BJ-Hughes Inc., Houston, TX (US);
Primary Examiner:
Int. Cl.
CPC ...
E21C / ;
U.S. Cl.
CPC ...
2426 / ;
Abstract
Improved rotary power slips having a housing for mounting in a rotary table of an earth drilling rig. Air is transferred from a stationary fluid source on the drilling rig to pneumatic cylinders carried by the housing when said housing is static to operate said slips. Transfer is accomplished by expansion of a perforated annular bladder thereby forming an expansive fluid duct between a stationary seal ring connected to the stationary fluid source and an air transfer plate which is rotatable with the housing.