主权项 |
1. A downhole dual cutting reamer for use in a wellbore with a wellbore axis configured for engaging a first bottom hole assembly on a first end and a second bottom hole assembly on a second end, wherein the downhole dual cutting reamer comprises a tubular body having an annulus, wherein the tubular body comprises:
a) a first end segment forming the first end having a first end segment outer diameter; b) a second end segment forming the second end having a second end segment outer diameter; c) a middle segment disposed between the first end segment and the second end segment with a middle segment outer diameter; d) a longitudinal axis extending from the first end through the middle segment to the second end; and e) a first cutting section extending longitudinally from the first end segment to the middle segment having a first cutting section outer diameter, the first cutting section comprising:
(i) a plurality of first cutting section helical blades, each first cutting section helical blade having a blade edge, and each first cutting section helical blade comprising:
1) a plurality of first cutting section helical blades, each first cutting section helical blade having a blade edge;2) a first spiral angled section increasing in radius from the first end segment to a midpoint of the first cutting section, wherein the midpoint intersects at a right angle to the longitudinal axis; and3) a second spiral angled section increasing in radius from the middle segment to the midpoint of the first cutting section;(ii) a plurality of first cutting section flutes, each flute disposed between a pair of helical blades, wherein each first cutting section flute has a flute depth greater than 0 percent and up to 25 percent less than the first end segment outer diameter and the middle segment outer diameter; and(iii) a first cutting section outer diameter greater than the end segment outer diameter and the middle segment outer diameter; f) a second cutting section extending longitudinally from the second end segment to the middle segment having a second cutting section outer diameter, the second cutting section comprising:
(i) a plurality of second cutting section helical blades, each second cutting section helical blade having an edge, each second cutting section helical blade comprising:
1) a second cutting section first spiral angled section increasing in radius from the second end segment to a midpoint of the second cutting section, wherein the midpoint intersects at a right angle to the longitudinal axis; and2) a second cutting section second spiral angled section increasing in radius from the middle segment to the midpoint of the second cutting section;(ii) a plurality of second cutting section flutes, each flute disposed between a pair of helical blades, wherein each flute has a flute depth greater than 0 percent and up to 25 percent less than the second end segment outer diameter and the middle segment outer diameter; g) at least one of: a plurality of thermally stable tungsten carbide cutting facings; a plurality of polydiamond cutting nodes; and a plurality of high strength carbide cutting nodes with raised surfaces disposed on the spiral angled sections; and h) as the downhole dual cutting reamer rotates about the longitudinal axis, each cutting member and the helical blades bidirectionally ream the wellbore while allowing drill fluid to flow down an annulus of the tubular body while simultaneously allowing wellbore particulates to flow up the wellbore and across the flutes. |