Reamer for Use in Drilling Operations

Abstract

The invention relates to reamers used downhole oil well operations, particularly in reaming while drilling applications.

I claim: 
     
         1 . A reamer for use in a downhole environment, comprising
 an annular body having a first end, a second end, and an exterior,   a plurality of cutting blades on said exterior, each of said blades comprising
 a first linear tapered section rising from said exterior from a point proximate said first end toward the midpoint of said body, 
 a second linear tapered section rising from said exterior from a point proximate said second end toward the midpoint of said body, and 
 a spiral section having a constant radius relative to said body joining said first tapered section to said second tapered section, 
   wherein said first linear tapered section and said second linear tapered section comprise a plurality of first cutting inserts, and said spiral section comprises a plurality of second cutting inserts.   
     
     
         2 . The device of  claim 1 , wherein said second cutting inserts comprise tungsten carbide. 
     
     
         3 . The device of  claim 1  wherein said second cutting inserts comprise a center depression in the top of said second cutting inserts. 
     
     
         4 . The device of  claim 2 , wherein said second cutting inserts comprise a center depression in the top of said second cutting inserts.