US2719027A

US2719027A - Drilling fluid nozzles for drill bits

Info

Publication number: US2719027A
Application number: US222212A
Authority: US
Inventors: Elvin G Boice; Robert G Peter
Original assignee: Reed Roller Bit Co
Current assignee: Reed Roller Bit Co
Priority date: 1951-04-21
Filing date: 1951-04-21
Publication date: 1955-09-27
Anticipated expiration: 1972-09-27

Description

2 Sheets-Sheet 1 Filed April 21, 1951 6 F M .6 f

IN VEN TORJ' A TTORNfYJ Sept. 27, 1955 E, G. BOICE ET AL 2,719,027

DRILLING FLUID NOZZLES FOR DRILL BITS Filed April 21, 1951 2 Sheets-Sheet 2 E/V/U 6. BO/Ce /6 Roberf 6. Pefer w '7 Av Iii d CZMZ g y/Z. v gay/1 5 5 Lia/"1A A T TORNE Y6 United States Patent DRILLING FLUID NOZZLES FOR DRILL BITS Elvin G. Boice and Robert G. Peter, Houston, Tex., as-

signors to Reed Roller Bit Company, Houston, Tex., a corporation of Texas Application April 21, 1951, Serial No. 222,212

2 Claims. (31. 2ss 313 This invention relates to new and useful improvements in drilling fluid nozzles for drill bits.

As is well known, the usual drill bit is provided with fluid circulating passages through which the usual drilling fluid is directed during the drilling operation. This drilling fluid usually contains abrasive material and is circulated in relatively high volume and under relatively high pressure. The flow of fluid is conducted downwardly through the connecting pin at the upper end of the bit and is then directed outwardly in a manner to eifectively clean the cutter teeth and remove detritus. Because of increased volumes and pressures which have come into use in recent years, the maintenance of the life of the fluid nozzles has presented a considerable problem.

It is one object of this invention to provide an improved drilling fluid nozzle adapted to be mounted within a drill bit which is constructed to withstand the abrasive laden drilling fluid under high pressure and in high volume.

An important object of the invention is to provide an improved nozzle assembly for drill bits which is constructed to eliminate constrictions, cavities and abrupt section changes so as to provide for a streamlined flow through the nozzle, whereby the drilling fluid is directed into the nozzle outlet with a minimum amount of turbulence.

Another object of the invention is to provide an improved nozzle assembly wherein each nozzle is, in eifect, an elongate passage which extends from the upper portion of the bit, whereby the division of the flow stream into the various nozzles occurs at a point remote from the outlet end of each nozzle to thereby prevent undue abrasive wear of the nozzle outlets.

Still another object is to provide an improved method of manufacturing a nozzle assembly wherein multiple nozzles may be individually constructed in sections which are adapted to be secured together to form the complete assembly, each nozzle having its internal passage arranged without abrupt turns or restrictions to permit substantially streamlined flow therethrough.

. A still further object is to provide an improved method of constructing a nozzle assembly wherein the individual nozzles are assembled and secured together and are thereafter welded in proper position within the bit assembly.

Still another object is to provide an assembly of the character described wherein the nozzle may or may not have a hardened insert at its outlet end.

The construction designed to carry out the invention will be hereinafter described together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

Figure l is a vertical sectional view taken through a drill bit and illustrating the improved nozzle assembly mounted therein,

Figure 2 is an isometric view of the nozzle assembly,

Z ,7? l 9 ,@Z 7 Patented Sept. 27, 1955 'ice Figure 3 is an isometric view of the two sections of the nozzle assembly illustrated in Figures 1 and 2,

Figure 4 is a side elevation of one of the nozzles,

Figures 5 to 9 are transverse sectional views taken on the lines 55 to 9-9, respectively, of Figure 4 to illustrate the cross-sectional shape of the passage through each nozzle,

Figure 10 is a transverse sectional view taken on the line 1010 of Figure 2,

Figure 11 is a sectional detail showing a hardened insert within the outlet end of the nozzle, and

Figure 12 is a transverse sectional view taken on the line 1212 of Figure 2.

In the drawings, the numeral 10 designates a typical drilling bit which includes a body 11 having cutters 12.

The bit illustrated is generally referred to as a jet type bit wherein fluid streams under high velocity are directed downwardly and outwardly against the formation being drilled. For directing these fluid jets it has been the practice to form openings or nozzles in the bit body adjacent the cutters; these openings or nozzles are usually at an angle to the axial bore of the body and cause a rather abrupt change in the line of fluid flow with the result that the abrasive material in the circulating fluid cuts out or damages the nozzles before the bit cutters are fully worn. The present invention has to do with the provision of an improved nozzle construction applicable to the typical jet bit for directing the fluid streams in the desired direction.

The improved nozzle construction is clearly shown in Figures 1 to 3 and includes a pair of duplicate sections or units A and B. Each section includes an upper generally semi-cylindrical portion 13 which has its lower end merging into a tapered tubular nozzle portion 14 which is disposed at an angle to said body portion, and said sections are adapted to interflt with each other to form a complete nozzle assembly (Figure 2). The nozzle assembly is arranged to be mounted within the bore 10a of the bit body which bore has itslower end flared at ltlb to accommodate the inclined or flared nozzle portions. When the assembly is within the bit (Figure 1) the lower outlet end of each nozzle portion is disposed in proper position above the bit cutters 12 to properly direct or jet the fluid in a desired manner.

As has been noted the upper portion 13 of each of the units A and B is generally semi-cylindrical in cross-section and the outer surface 13a is curved while the inner surface 13b is substantially flat. At the juncture of the flat inner surface 13b with the tubular nozzle portion the surface of each unit is curved as indicated at 13c; the flat surface 13b gradually merges into the surface 13c and the nozzle portion 14 is oifset or out of longitudinal alignment with the longitudinal axis of the upper portion 13, whereby the recess 13 is formed along one edge of the portion 13 adjacent the juncture between the

portions

13 and 14. When the flat surfaces 13b of the sections A and B are placed in abutting contact relationship, the surfaces 13c which are complementary to each other engage to result in perfect interfitting of the two units as shown in Figure 2. The complete assembly comprises the upper cylindrical portion having the flared or inclined nozzles extending from its lower end in substantially diametrically opposed relationship.

The two units A and B of the nozzle assembly are welded together and the inner walls 13d of the connected units coact to form a central partition or web extending longitudinally of said assembly to divide the assembly into two flow passages C and D. The transverse center line 13c (Figure 10) of the web formed by the abutting walls of the units lies in a vertical plane V which is substantially parallel to the planes V (Figure 12) which may be termed the longitudinal axes of the nozzle portions 14 of said unit; the lower end of the passage C communicates with the bore of one of the nozzles while the second passage D has communication with the bore of the other nozzle. As is clearly shown in Figure 4, the particular disposition of the dividing web with respect to the nozzles permits the bore of each nozzle to become in effect a gradual continuation of its associated passage without any abrupt turn or offset in the passage. The complete assembly comprising the connected units A and B is then welded or otherwise suitably secured within the bit body, the weld being indicated at 15 in Figure 1.

It is noted that heretofore it has been the practice to dispose the dividing web in a longitudinal. plane which is at a right angle to the plane in which the longitudinal axis of each nozzle lies; in other words, referring to Figure 12, the web has been disposed in a plane indicated by the dotted line L and when so disposed the fluid was caused to make a relatively sharp turn from the upper end of the assembly into the bore of the nozzle. By disposing the web in a longitudinal plane which is substantially parallel to a plane through the longitudinal axis of the nozzle, a more gradual flow path without any abrupt curves is possible and true streamlined flow through the assembly results.

Each passage or bore C and D which extends entirely through the portion 13 of its respective unit and merges with the bore of its associated nozzle has the cross-sectional shape thereof varied from its upper to its lower end, as is clearly illustrated in Figures 5 to 9. At the upper end of each unit the bore 16 is substantially semicircular in cross-section and as the bore reduces toward its lower end, the shape is gradually changed from semicircular in cross-section toward circular, as illustrated in Figure 7; as the passage merges into the bore of the nozzle it is of a shape as shown in Figure 8 and therebelow the bore of the nozzle gradually changes to truly circular, as shown in Figure 9. This gradual change of the shape of the passage through each unit is permitted because of the disposition of the dividing web and provides for a smooth streamlined flow through said passage; thus, after the drilling fluid is divided into two streams by the central web, each stream enters the relatively large upper end of each passage and thereafter there is no abrupt change in the direction of flow or a subsequent dividing of the flow, with the result that minimum abrasion of the interior surface of the passages and nozzle bores is had.

From the foregoing it will be evident that the passage or bore through the units provides a relatively streamlined path for the flowing fluid, whereby any abrasive wear will be spread over the large area of the entire passage or bore and will not cause undue wear at any particular point. The partition or web section formed by the abutting fiat inner walls 13b of the two sections functions to divide the two nozzles flow stream into two flow paths which are conducted to the outlet end of the nozzle with a minimum amount of deflection of the fluid stream, whereby the fluid streams are ejected from the nozzles at the desired positions in relation to the bit. The construction of the nozzle assembly in two separate 4 units which are identical in construction facilitates casting of the units and also allows individual testing of each unit prior to assembly. Also, after the two sections are secured together the central web provides for a reinforcing rib extending throughout the entire length of the assembly.

It may be desirable to mount a hardened insert in the outer end of each nozzle and in Figure 12, such a construction is illustrated. In this instance, the outlet end of the bore of the nozzle is counterbored to receive a collar or sleeve N which may be secured therein in any suitable manner, and said collar or sleeve is constructed of hardened metal or other suitable wear-resisting material.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

Having described the invention, we claim:

1. A nozzle assembly for drill bits including a plurality of sections adapted to interfit and be secured together to form a unitary structure, each section comprising an upper tubular portion which is substantially semi-circular in cross-section whereby one wall of said portion is substantially flat, said portion extending in axial alignment with the drill bit in which the structure is mounted, and a lower nozzle portion which is disposed at an angle to the bit axis, each of said sections also having a longitudinal passage extending entirely through both its upper portion and its nozzle portion, the fiat wall of the upper portion lying in a longitudinal plane which is substantially parallel to a longitudinal plane through the axis of the nozzle portion and perpendicular to a plane from which said lower nozzle portion is offset.

2. A nozzle assembly as set forth in claim 1, wherein said lower nozzles are offset from a plane perpendicular to the plane of the flat wall of each of said upper portions, and wherein said longitudinal passage is larger in crosssection at its upper end than at its lower end and wherein the variation in cross-sectional area is gradual from end to end of said passage, whereby no abrupt changes in direction of flow occur within said passage.

References Cited in the file of this patent UNITED STATES PATENTS 444,054 Lazarus Jan. 6, 1891 1,073,963 Cottle Sept. 23, 1913 1,730,348 Anstiss Oct. 8, 1929 1,754,671 Dahl Apr. 15, 1930 1,804,264 McDevitt May 5, 1931 1,945,258 Collins Jan. 30, 1934 2,016,019 Muvrin Oct. 1, 1935 2,068,327 Howard et al Jan. 19, 1937 2,221,242 McClelland Nov. 12, 1940 2,279,129 Pennington Apr. 7, 1942