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Publication numberUS3554307 A
Publication typeGrant
Publication dateJan 12, 1971
Filing dateJul 3, 1969
Priority dateJul 3, 1969
Publication numberUS 3554307 A, US 3554307A, US-A-3554307, US3554307 A, US3554307A
InventorsYount Nolen A
Original AssigneeYount Nolen A, W E Eeds
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Turbulent flow drill collar
US 3554307 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

United States Patent lnventor Appl. No.

Filed Patented Assignee Nolen A. Yount Beeville, Tex.

July 3, 1969 Jan. 12, 1971 W. E. leds Beeville, Tex. a part interest TURBULENT FLOW DRILL COLLAR 5 Claims, 3 Drawing Figs.

US. Cl.

Int. Cl.

References Cited UNITED STATES PATENTS 9/ 1964 Fox 3,175,374 3/1965 Toelke FZlb 17/00 Field ofSenrch ill 3,338,069 8/1967 Ortloff 64/1 3,360,960 1/1968 Massey 64/1 FOREIGN PATENTS 206,517 2/1909 Germany 175/320 Primary Examiner-James A. Leppink Attorneys-Clarence A. OBrien and Harvey B. Jacobson ABSTRACT: A tubular drill string member having grooves formed in the outer surface thereof extending circumferentially thereabout and longitudinally thereof. The grooves include short sections or lengths of first groove portions which generally parallel the longitudinal centerline of the tubular drill string member or drill collar and short sections or lengths of second groove portions which are inclined generally 15 relative to a plane nonnal to the longitudinal centerline of the drill collar. The second groove portions interconnect the adjacent ends of adjacent first groove portions and the first and second groove portions of each groove are disposed generally in a helical path extending along and about the corresponding drill collar.

tion of the drilling stringimmediately above the drilling bit.

A drill collar is made in various 1 diameters and wall thicknesses whereby the in eight of the drill collarper-unit of its length may vary greatly. Because Jdrilling bits have been greatly improved it is now possible to increase the weight on the drillingbit so as toincrease the rate of penetration of the bit. The weight on thebit is controlled,.t o a great extent, by the size and number of drill collars disposed above the bit. As additioiial drill'collars are added to the bottom end of a drill stri'ng,ythe friction of the drill collars in the well bore is increased The outerdiaineter ofthe collars used isless than the outside diameter of the associated drill bit whereby drilling fluid or mud being pumped'through the drill bit is permitted to move upwardly in the well bore about theldrill collars toward the upper end of the well bore.

It has been found desirable at times to decrease the opening in the drillingbit through which the drilling fluid passes resulting in a decrease in the amount-of drilling fluid which may pass "to ball or stick together. This can increase hydrostatic pres-' sure in the well bore and the increase'in hydrostatic pressure can cause a breakdown in. formation porosity and loss of drilling fiuideWhen drilling fluid loss is experiencedthere is a great possibility of sticking the drilling string in the hole. A stuck drilling string is freedonly after expensive fishing jobs and it sometimes causes a well to blow out.

The object of this invention is to :provide a drill collar serving to create a turbulent flow of drilling fluid about the drill collars during return of the drilling fluid to the upper end of the well bore. This turbulent flow. will increase the speed of the drilling fluid and the-cuttings as they move toward the upper end of the bore and it willkee'p the drilling cuttings from balling up-and sticking. Further, it will decrease the hydrostatic pressure 'inthe bore.

Another object of this invention is to provideatubular drill collar which will serve to prevent mud cake from buildingup in the well bore throughout a formationwith porosity.

The turbulent flow -drill'collar of the instant invention further has as its objects the general objects of :a drill collar such as thatdisclosedin US. Pat. No, 2,999,552.

A final object: "of this invention to be specifically 'enumerated herein is to provide a drill collar in accordance with the precedingobjectsand which will conform to conventional forms of manufacture, be-of simple construction and easy to use so as to provide a'device that will be economically feasibIeJong lasting and relatively trouble free in operation.

These together with other objects and advantageswhichwill become subsequently apparent "reside :in .the details of con: struction and operation .as more fully hereinafter described and claimed, reference being had to the accompanying drawing'siforming a-part hereof, wherein-like numeralsrefer to likespartsthroughout, andlin which;'

FIG. 1 is anelevationalviewof the improveddrillcollar of the instant invention with portions of the upper end thereof being broken away and illustrated in vertical section;

FIG. ,2 :is an enlarged fragmentary vertical sectional :view taken substantiallyupon the plane indicated by the section line2-2 ofFlG. l; and t Y 3 FIG. 3 is an enlargedvhorizontal sectionalview taken sub FIG. 1.

Referring now more specifically to thedrawings, the nu rrieral 10 generally designates the drill collar of the instant in= vention. The collar 10 is generally conventional in that one end thereof is internally threaded as at '12 and the other end thereof is externally threaded as at l4. However, the collar 10 includes a pair of grooves referred to in general by the reference numerals 16 and 18 which extend along and about the drill collar 10 in generally helical paths. Each of the grooves 16 includes first groove portions 20 and second groove portions 22. The first portions 20 generally parallel the longitudinal center line of the drill collar 10 and the second groove potions are inclined approximately l5 relative to a plane normal to the longitudinal center line of the drill collar 10. Each groove portion 22 interconnects the adjacent ends of a pair of adjacent first groove portions 20 and in this manner substantially all portions of the grooves 16 and 18 either generally parallel or are disposed substantially normal to the direction of movement of adjacent peripheral portions of the drill collar during rotation of the latter.-

As can best be seen from FIGS. 2 and 3 of the drawings the cross-sectional shape of the groove portions 20 and 22 is dissimilar. The groove portions 20 are substantially V-shaped in cross section including a pair of relatively inclined opposite sidewalls 26 and 28. The groove portions 22 also include relatively inclined opposite sidewalls 30 and 32, but the inner marginal edge portions of the sidewalls 30 and 32 are connected by a bottom wall 34.

it will be noted that the relatively inclined sidewalls 26 and .28 of the groove portions 20 do not offer any edges which would tend to cause displacement of the associated drill string in either longitudinal direction upon engagement of the portion of the drill collar 10 about one of the grooves 20 with the walls of the well bore during rotation of the drill collar 10. Further, the groove portions 22 are free of cutting edges and are short in circumferential extent, whereby any tendency of the grooves 22 to longitudinally displace the drill collar 10 during rotation of the latter by contact with the well bore will be brief.

The groove portions 22 are inclined l5 relative to a plane normal to the longitudinal center line of j the drill collar although the inclination of the groove portions 22 may vary 2 or 3, or possiblymore, above and below an inclination of 1 5.

The particular configurations of the grooves 16 and 18 prevent the drilling cuttings fromballihgupziiid sticking by increasingthe turbulence of the drilling fluid as it passestoward the top of the well bore. Further, the hydrostatic pressure of the drilling fluid within the well bore ;is reduced and mud cake is prevented from building up in the well bore. Also, "the for mation of the grooves 20 and 22 provide-a means to insure that drilling fluid is disposed on all sides ofthe drill collar Ill. Thus, the drill collar -10 is lubricated and any tendeneyfor the drill collar to stick in the-well bore is reduced.

Furthergby having thegroove portionsi20 parallel the lam gitudinal axis of thedrill collar 10 and the groove portions 22 disposed substantially normal to the longitudinal axis of the drill'collar" 10, there are nooutersurfaceportions-of the drill collar which would tendto cause rotation of the lowerend of the drill string as it is being lowered into the bore. it is not unusual for drill strings having drill collars thei'eofprovidedwith smoothly curving helical grooves to cause apor'tioti of-the drilling string to be unthreaded while the drill string-isbeiiig lowered into the well bore. Whe'n'this happens, the lower end of the drilling string drops to the bottom of the wellboi-e and must be retrieved by specific fishing tools lowered into the bore.

By having the grooves 16 and 18 "steppedg" tliere is-sub= stantially no tendencyfor the lower end of-the drillingstringte unscrew from the upper end of-the drilling string asthestring' is being lowered into the well and; portions ofthe loweriend of the string contact the wellbore.

The foregoing is considered as illustrativeonlyof tl'i'e'ir'rinei= ples of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, i't is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

I claim:

1. An elongated upstanding tubular member for connection in a drill string, said Lubular member having at least one generally helical groove in its outer peripheral surface, said groove including alternating first and second groove portions whose adjacent ends are communicated, said first groove portions generally paralleling the center line of said tubular member and said second groove portions being inclined generally relative to a plane normal to said center line said groove portions being each of a length less than the outside diameter of said tubular member, the lower sidewall portions of the second groove portions being generated by a spirally displaced radius of said tubular member and the upper sidewall portions of said second groove portions being upwardly and outwardly inclined.

2. The combination of claim 1 wherein said first groove portions are generally V-shaped in cross section.

3. The combination of claim 1 wherein said second groove portions are generally trapezoidal in cross section.

4. The combination of claim 3 wherein said first groove portions are generally V-shaped in cross section, the sidewalls of said first groove portions being inclined less than 45 relative to radii of said tubular member passing through said groove portions.

5. The combination of claim I wherein the outer surface portions of said tubular member through which said groove portions open are generally cylindrical.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3146611 *Oct 11, 1961Sep 1, 1964Fox Fred KTubular drill string members
US3175374 *Jun 22, 1962Mar 30, 1965Probe IncTubular member for use in well drilling operations
US3338069 *Mar 11, 1965Aug 29, 1967Exxon Production Research CoRotary drill collar
US3360960 *Feb 16, 1966Jan 2, 1968Houston Oil Field Mat Co IncHelical grooved tubular drill string
DE206517C * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4811800 *Oct 22, 1987Mar 14, 1989Homco International Inc.Flexible drill string member especially for use in directional drilling
US5040620 *Oct 11, 1990Aug 20, 1991Nunley Dwight SMethods and apparatus for drilling subterranean wells
US5465799 *Apr 25, 1994Nov 14, 1995Ho; Hwa-ShanSystem and method for precision downhole tool-face setting and survey measurement correction
US5535837 *Jul 5, 1994Jul 16, 1996Grant Prideco, Inc.Helical stress relief groove apparatus and method for subterranean well drill pipe assemblies
US7377315Nov 29, 2005May 27, 2008Hall David RComplaint covering of a downhole component
US7497254Mar 21, 2007Mar 3, 2009Hall David RPocket for a downhole tool string component
US8091627Jan 10, 2012Hall David RStress relief in a pocket of a downhole tool string component
US8161619 *Nov 2, 2007Apr 24, 2012The Boeing CompanyJoint for hybrid composite items
US8201645Jun 19, 2012Schlumberger Technology CorporationDownhole tool string component that is protected from drilling stresses
US8430759 *Apr 30, 2013The Boeing CompanyJoint for composite tube
US20070119589 *Nov 29, 2005May 31, 2007David HallComplaint Covering of a Downhole Component
US20080230277 *Mar 21, 2007Sep 25, 2008Hall David RPocket for a Downhole Tool String Component
US20090025982 *Jul 26, 2007Jan 29, 2009Hall David RStabilizer Assembly
US20090116898 *Nov 2, 2007May 7, 2009Wanthal Steven PJoint for hybrid composite items
US20100018699 *Oct 7, 2009Jan 28, 2010Hall David RLow Stress Threadform with a Non-conic Section Curve
US20100051256 *Mar 4, 2010Hall David RDownhole Tool String Component that is Protected from Drilling Stresses
US20120183347 *Jul 19, 2012The Boeing CompanyJoint for composite tube
EP0178709A1 *Sep 24, 1985Apr 23, 1986DIAMANT BOART Société AnonymeStabilizer
U.S. Classification175/323, 464/183
International ClassificationE21B17/22, E21B17/16, E21B17/00
Cooperative ClassificationE21B17/22, E21B17/16
European ClassificationE21B17/16, E21B17/22