US2900171A

US2900171A - Erosible nozzle for roller bit

Info

Publication number: US2900171A
Application number: US288626A
Authority: US
Inventors: Elvas A Miller; Duke A Johnson
Original assignee: Reed Roller Bit Co
Current assignee: Reed Roller Bit Co
Priority date: 1952-05-19
Filing date: 1952-05-19
Publication date: 1959-08-18
Anticipated expiration: 1976-08-18

Description

Aug-1s; 1959 E. A. MILLER ETAL 2,900,171 EROSIBLE NO'ZZLE- FOR ROLLER BIT 2 Sheets-Sheet 1 Filed May 19, 1952- fluke A. dob/7600 5/1/00 A. M///er INVENTORJ y. WM 244m 2' Aug-1s, 1959 I E. A. MILL R EI'AL 2,900,171

'EROSIBLE NOZZLE FOR ROLLER BIT Filed May 19. 195 2 v 2 Sheets-Sheet 2 Duke 4/0/7/760/7 5/1 06 /4.-M///er INVENTORJ QWM 77710-21, BY 0 2,5. M EKM ATTORNEY) EROSIBLE NOZZLE non ROLLER BIT Elvas A. Miller and Duke A. Johnson, Oklahoma City,

Okla., assignors to Reed Roller Bit Company, Houston, Tex., a corporation of Texas This invention relates generally to drill bits and more particularly to the means in roller drill bits for directing drilling fluid pumped therethrough.

In the drilling of deep wells, a drill bit is attached to the end of a drill stem and lowered to the bottom of the hole. The drill stem is then rotated causing the drill bit to penetrate the formation, and drilling fluid is pumped downwardly through the drill stem and drill bit to remove the cuttings dislodged by the drilling operation and carry them upwardly, in the space between the drill stem and the wall of the hole, to the surface of the earth. Drill bits in common use may be provided with rollers to cut or crush the formation, and may be provided with nozzles to discharge drilling fluid toward the bottom of the hole, so that cuttings or particles of formation dislodged by the bit during the drilling operation may be removed from the bottom of the hole. However, in certain instances, the drill bit may become packed or balled up when lowered by the drill stem to the bottom of the hole; that is, the cuttings dislodged by previous drilling operations, and other material or detritus already in the hole, may accumulate about the rollers and pack the drill bit, as the drill bit.is being lowered into the hole. Balling up of the drill bit may occur particularly in those roller bits in which the drilling fluid is discharged from the bit head toward the bottom of the hole. Accordingly, the nozzles serving to discharge the drilling fluid toward the bottom of the hole may not serve to clean the rollers and adjacent parts properly. As a result of this, the rollers may not freely rotate when the drill stem is rotated and the bit therefore does not efficiently drill the formation.

A general object of this invention is to provide a drill bit having new and improved nozzles which will serve not only to discharge fluid directly toward the bottom of the hole but also to clean the bit of accumulated cuttings and detritus.

A specific object is to provide a new and improved bit in which the drilling fluid pumped through the drill stem will be initially utilized to clean the drill bit and, after the bit has been cleaned, the drilling fluid will be discharged directly toward the bottom of the hole to remove the cuttings dislodged by the bit during the drilling of the well.

Another specific object is to provide a nozzle having a diverter which will cause drilling fluid pumped through said nozzle initially to clean the drill bit; said diverter being adapted to be rendered ineffective thereafter by the action of the drilling fluid, whereupon said nozzle will gislcharge the drilling fluid toward the bottom of the Other objects will hereinafter appear from the following description and the accompanying drawings wherein, by way of example, one embodiment of this invention is set forth.

In the drawings:

Fig. 1 is a section taken on line 1-1 of Fig. 2.

United States Patent Patented Aug. 18, 1959 ice Fig. 2 is a bottom plan view of a drill bit showing the positions of the drilling fluid nozzles in the bit.

Fig. 3 is a fragmentary sectional view showing thedrilling fluid diverter.

Fig. 4 is a fragmentary sectional view showing the drilling fluid diverter after it has been rendered inefiective by the action of the said fluid.

Fig. 5 is an isometric view showing in detail the drilling fluid diverter attached to the lower end of the fluid nozzle.

Referring to Figs. 1 and 2, the drill bit is indicated generally by the character A and the bit head is indicated at 1. The bit head 1 may have oppositely disposed side roller bearing extensions 2 and oppositely disposed cross roller bearing extensions 3. Side rollers 4 may be rotatably mounted in the usual manner on said side roller bearing extensions 2 and cross rollers 5 and 6 may be rotatably mounted in the usual manner on cross roller bearing extensions 3. The inner ends of the

bearing extensions

2 and 3 may be secured to a bridge 15. The bit has a threaded shank 7 which is adapted to be connected to a drill stem (not shown). As can be seen in Fig. 1, a drilling fluid nozzle 8 is disposed within the bore 9 of the shank 7. The nozzle 8 has downwardly and outwardly diverging fluid passageways It). The low er ends 11 of the nozzle 8 may be directed to discharge drilling fluid toward the bottom of the hole. A wear resisting insert 16 may be provided in the lower end 11 of the nozzle 8. A drilling fluid diverter 12 is attached to the end 11 by means of brazing or other suitable means. The diverter 12 is adapted to divert initially drilling fluid, being discharged from the ends 11 of the fluid nozzle 8, toward the rollers 4, 5 and 6 and toward the recess 13 immediately above the said rollers. The recess 13 above the said rollers is formed by the lower portion of the bit head 1, the side roller bearing extensions 2 and the cross roller bearing extensions 3.

As shown in Fig. 5, the diverter 12 may be in the form of a hollow spherical wedge, a quarter of a spherical shell or any other suitable shape. The diverter 12 may have a saw-cut 14 or other separation or may be 1 scored for the purpose of accelerating the erosion thereof caused by the'action of the drilling fluid impinging thereon. The diverter 12 may be made of sheet metal or other suitable material. Thus it can be seen that the diverter 12 will initially act to divert the drilling fluid being pumped through the drill stem and through the drilling fluid nozzle substantially inwardly towards the drill bit to remove detritus and cuttings which may have accumulated about said cutters and in the recess 13, as the drill bit was beiig lowered into the hole. Continued impingement of the drilling fluid upon the diverter 12 will cause it to become inoperative and it may become eroded away by the action of the drilling fluid impinging on the said diverter.

Fig. 3 shows schematically how the diverter 12 may act to direct the drilling fluid to clean the drill bit rollers and adjacent parts, and in Fig. 4, the diverter 12 is shown after having been rendered inoperative by the action of the drilling fluid impinging thereon, whereupon the drilling fluid now is directed toward the bottom of the hole and is no longer being diverted towards the drill bit rollers by the diverter 12.

In operation, the drill bit A is secured by means of a threaded shank 7 to the end of a drill stem (not shown) which is then lowered to the bottom of the bore hole and rotated to cause the drill bit-to penetrate the formation. During the lowering thereof, the drill bit may have become ,balled up or packed with cuttings standing in the hole, which have been dislodged during previous drilling operations. The cuttings may accumulate about the side rollers 4 and

cross rollers

5 and 6 and 3 especially in the recess 13 above said rollers. The drill bit may thus become bailed up before it is rotated on the bottom of the hole. This balling up or packing of the drill bit maybe so severe that the rollers may not turn properly, upon rotation of the drill stem, and thus may skid and be worn flat, materially reducing the useful life of the drill bit. In order to alleviate this condition, -we have provided the drilling fluid diverter 12 which will act initially to divert drilling fluid being pumped through the drill stem to clean the drill bit of the cuttings and detritus packed therein, as above described. Continued impingement of the drilling fiuid on the said drilling fluid diverter 12 will cause it to become inoperative to divert said fluid; whereupon, the fluid will then be directed toward the bottom of the hole to remove therefrom the cuttings dislodged during the drilling operation.

Our invention is not limited to the embodiment shown. Various changes, within the scope of the following claims, will be apparent to those familiar with the art.

We claim:

1. A cross roller bit having a head, cross rollers and side cutters mounted in the lower portion of said head with a recess formed thereabove, said head having a drilling fluid discharge passageway provided with a nozzle at its discharge end for directing the drilling fluid in a straight line course, means for diverting the drilling fluid from said straight line course and turning it inwardly towards said cutters consisting of a hollow substantially spherical thin-walled metal member having a portion thereof open and inwardly directed towards said cutters and mounted on the lower end of said passageway whereby said drilling fluid is initially turned toward the central portion of the bit so as to be directed onto said rollers and cutters and into said recess to clean the bit, said diverting means having a portion of its wall where the straight line directed drilling fluid impinges thereagainst preliminarily weakened so that the drilling fluid will by eroding action ultimately destroy substantially all of said diverting means whereby the formerly inwardly turned drilling fluid is again returned to its straight line course and directed toward the bottom of the hole being drilled by said bit.

2. A cross roller bit having a head, cross rollers and side cutters mounted in the lower portion of said head with a recess formed thereabove, said head having a drilling fluid discharge passageway provided with a nozzle at its discharge end for directing the drilling fluid in a straight line course, means for diverting the drilling fluid from said straight line course and turning it inwardly toward said cutters consisting of a substantially spherical thin-walled metal member having an outer wall portion, a weakened bottom wall portion and an inwardly directed open wall portion directed towards said cutters and mounted on the lower end of said passageway whereby said drilling fluid is initially turned toward the central portion of the bit so as to be directed onto said rollers and cutters and into said recess to clean the bit, said weakened bottom wall portion serving to form a surface against which the straightline directed drilling fluid may impinge and by eroding action ultimately destroy substantially all of said diverting means whereby the formerly inwardly turned drilling fluid is again returned to its straight line course and directed toward the bottom of the hole being drilled by said bit.

3. A cross roller bit having a head, cross rollers and side cutters mounted in the lower portio of said'head with a recess formed thereabove, said head having a drilling fluid discharge passageway provided with a nozzle at its discharge end for directing the drilling fluid in a straight line course, means for diverting the drilling fluid from said straight line course and turning it laterally inwardly 'with respect to the sides of said bit head and towards said cutters consisting of a hollow substantially spherical thin-walled metal member having a portion thereof open and inwardly directed towards said cutters and mounted on the lower end of said passageway whereby said drilling fluid is initially turned toward the central portion of the bit so as to be directed onto said rollers and cutters and into said recess to clea the bit, said diverting means having a portion of its wall where the straight line directed drilling fluid impinges thereagainst preliminarily weakened so that the drilling fluid will by eroding action ultimately destroy substantially all of said diverting means whereby the formerly inwardly turned drilling fluid is again returned to its straight line course and directed toward the bottom of the hole being drilled by said bit.

References Cited in the file of this patent UNITED STATES PATENTS Gage Apr. 22, 1941