A hybrid bit with roller cone having inserts

Abstract

The present disclosure relates to a hybrid bit with roller cone having inserts, comprising a bit body, blades disposed with the bit body, a plurality of fixed cutting elements arranged side by side along the outer edge of blades and roller cones mounted with the said bit body in circumferential and alternate arrangement with the said blades, the said roller cones having multiple rows of cone inserts arranged side by side along the meridian direction of cones, and the said cones having multiple rows of cone inserts arranged side by side along the weft direction of cones, the cutting insert rows of adjacent two cones herein are in alternate arrangement, the cutting insert rows of adjacent two cones are in derangement and the insert placement structure in the plurality of cones is the same.

What is claimed is: 
     
         1 . A hybrid bit with roller cone having inserts, comprising:
 a bit body;   a plurality of blades disposed on the bit body;   a plurality of fixed cutting elements arranged side by side along the outer edge of a plurality of blades; and   a plurality of roller cones mounted with the said bit body in circumferential and alternate arrangement along the said bit body, the said cones having plurality rows of cone inserts arranged side by side along the meridian direction of cones, and the said cones having plurality rows of cone inserts arranged side by side along the weft direction of cones, the cutting inserts of adjacent two cones herein among the said cutting insert rows are in alternate arrangement, the cutting insert rows of adjacent two cones are in derangement and the insert placement structure in a plurality of cones is the same.   
     
     
         2 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein the insert placement structure comprises:
 the distance between a row of cone inserts and a central axis of the bit body;   the space between two adjacent rows of cutting inserts;   the space of cutting insert rows between two adjacent cones among the cutting rows of inserts;   the shape of cone inserts; and   the size of cone inserts.   
     
     
         3 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein nozzles for jetting cutting fluid mounted at the said bit body. 
     
     
         4 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein a head is disposed between at least two adjacent blades circumferentially with its upper end integrated with the bit body, and a cone disposed at its lower end. 
     
     
         5 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein the said blade comprises the inner cone, nose, shoulder and gage sections from inside to outside, and a plurality of the said fixed cutting elements are arranged side by side at the inner cone, nose, shoulder and gage sections. 
     
     
         6 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein the fixed cutting elements at a plurality of the said blades are arranged differently, and the said cutter placement includes the distance between the fixed cutting elements and the center of the said bit body. 
     
     
         7 . The hybrid bit with roller cone having inserts according to  claim 6 , wherein a plurality of fixed cutting elements are disposed side by side from inside to outside of each of the said blades to cover the whole bottom-hole, and the gyration radiuses of all the cutting elements in blades are different as well. 
     
     
         8 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein the outermost profile envelope of cone cutters herein and the profile envelope of fixed cutting elements are in parallel and spaced from 0 mm to 2.0 mm in the direction away from the axis of the said bit body, and the outermost profile of said cone inserts is closer to the inside or closer to the outside than the said profile envelope of the said fixed cutting elements. 
     
     
         9 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein at the lowest point of cutting trajectory, the center line of the said cone inserts extending circumferentially overlaps with or approximates to the center line of one cutting element of a blade extending circumferentially along the said bit body. 
     
     
         10 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein,
 there are 2-6 blades;   there are 2-6 roller cones; and   the number of roller cones are equal to or less than blades numbers.   
     
     
         11 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein,
 the roller cone comprises 6-20 rows of cutting inserts; and   each row of cone inserts comprises 6-20 cutting inserts.   
     
     
         12 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein the cone inserts are cemented carbide inserts or mixed cutting elements with cemented carbide and polycrystalline diamond. 
     
     
         13 . The hybrid bit with roller cone having inserts according to  claim 1 , wherein the fixed cutting elements are diamond cutters.