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. 29, 1999
Filed:
Apr. 04, 1997
Gary R Portwood, Kingwood, TX (US);
Scott D McDonough, Houston, TX (US);
Dennis Cisneros, Kingwood, TX (US);
Smith International, Inc., Houston, TX (US);
Abstract
A cutter element having a substantially flat wear face and leading compression and trailing tension zones, wherein the leading compression zone is sharper than the trailing tension zone. Sharpness is defined as either a smaller inside angle at the intersection of a pair of planes or as a smaller radius of curvature. The cutter element of the present invention experiences reduced stress on its trailing portion in the direction of cutting movement and therefore is less subject to extreme impact damage and cyclic fatigue. The present invention can be applied with particular advantage to heel row cutters, but can also be applied to cutters in other rows that primarily ream the borehole wall and cooperatively cut the borehole corner. The present cutter element can be constructed so as to have either a positive or negative rake angle at its leading compression zone, or to have any of a variety of shapes, depending on the characteristics of the formation in which it is to be used.