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:
Sep. 29, 1992
Filed:
May. 03, 1991
Dwight S Nunley, Gretna, LA (US);
Other;
Abstract
A component for attachment to a drillpipe which is part of a drillstring carrying a drillbit, said drillstring rotatably driven in a working direction, which drillpipe contains a standard box tool joint at one end and a standard pin tool joint at the other end, which tool joints are of a diameter greater than the section of drillpipe between the two joints, and which drillpipe component is comprised of two elongated cylindrical half sections for clamping over at least a portion of the narrower section of drillpipe and which component, on its outer surface, contains at least one helical pumping chamber having a twist, when viewed in axial elevation, opposite to that in which said drillstring is rotatably driven in said working direction, said pumping chamber, when view is traverse section, having an undercut portion relative to the surface of the drillpipe component, said undercut portion defining a lip.