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:
May. 07, 1991
Filed:
Sep. 27, 1989
Applicant:
Inventor:
Roderick D McLeod, Edmonton, Alberta, CA;
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
166 90 ; 166 95 ;
Abstract
Apparatus for isolating the wellhead equipment from the high pressure fluids pumped down to the producing formation during the procedures of fracturing and acidizing oil and gas wells utilizes a central mandrel concentric inside an outer mandrel and an expandable sealing nipple to seal the outer mandrel against the casing. The sealing nipple is provided with passageways to allow fluids to be pumped down the tubing and/or the annulus between the tubing and the casing in an oil or gas well.