US2028910A

US2028910A - Reamer

Info

Publication number: US2028910A
Application number: US709551A
Authority: US
Inventors: John W Macclatchie
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-02-03
Filing date: 1934-02-03
Publication date: 1936-01-28
Anticipated expiration: 1953-01-28

Description

Jam 28, 3936. J. W. M CLATCHIE REAMER Filed Feb. 5, 1934 INVENTOR. JOHN W MACCLATCHIE ATTORNEY.

Patented Jan. 28, 1936 srArs arcane FATENT OFFICE 14 Claims.

This invention is a rotary reamer for wells, and has for its object to enlarge a well bore to uniform gauge by means of a shearing cutting action rather than a mere scraping or swedging action, with the cutting contact at a plurality of arcuate areas circumferentially spaced around the tool and combining to provide a cutting engagement throughout an appreciable arc of the circumference of the well bore, and each circum- 10, ferentially successive cutting area longitudinally overlapping and projecting below the preceding cutting area. The entire circumference of the well bore may thus be uniformly enlarged, with the uniform enlargement continuous along the length of the well bore.

It is a further object of the invention to provide a cutting contact throughout an appreciable arc of the circumference of the well bore, but to so circumferentially space the areas of contact as to provide longitudinal channels therebetween of such area as to permit free passage of cuttings without liability of clogging the tool.

It is a still further object of the invention to provide a shearing cutting action as described, by means of an extremely simple and sturdy cutter element adapted for convenient assembly and replacement in a string of usual rotary drill pipe.

Further objects of the invention will be readily understood from the following description of the accompanying drawing, in which:

Fig. l is a side elevation of the reamer, partly in axial section.

Fig. 2 is a transverse section on the line 22 of Fig. 1.

Fig. 3 is a diagrammatic illustration of circumferentially successive teeth of trailing cutters of the cutter element, showing the relative vertical position of the teeth.

The cutter element is preferably an integral structure adapted for convenient assembly and replacement in a string of rotary drill pipe I; and for this purpose the cutter element is shown as a sleeve 2 adapted for sliding reception on a mandrel 3, with the lower end of the mandrel adapted for threaded connection with a lower portion of the string of drill pipe as shown at 4, and the upper end of the mandrel adapted for threaded engagement with a sub 5 as shown at 6, and the sub 5 connected to an upper portion of so the string of drill pipe by a threaded connection 7. Acirculation bore 8 extends through the mandrel and the sub, and communicates with the usual circulation bore of the string of drill pipe.

The sleeve 2 may be held against rotation on the mandrel by a tongue and groove connection 9 between the lower end of the sleeve and an annular shoulder ill of the mandrel, and the lower end of sub 5 may form an annular abutment H adapted to engage the upper end of sleeve 2 for releasably locking it against longitudinal dis placement on the mandrel.

A plurality of cutting teeth project radially from sleeve 2, and are preferably integral with the sleeve so as to provide a simple but sturdy construction. The plurality of teeth are adapted to engage the wall of the well bore for enlarging it to gauge both throughout its circumference and along the length of the bore; and for this purpose the teeth are circumferentially spaced around the sleeve 2 so that their combined cutting contact constitutes an appreciable arc of the circumference of the well bore, and each circumferentially successive tooth longitudinally overlaps and projects below the next preceding tooth.

As an instance of this arrangement vertical rows of cutters l5 project radially from the sleeve 2, the rows being equi-distantly circumferentially spaced and in the illustrated embodiment being shown as three in number. The cutters of each row are vertically spaced from one another, and the outer peripheries E6 of the cutters are curved concentric with the axis of the tool as shown at Fig. 2, so as to maintain contact with the wall of the well bore along the circumferential length of the cutters. The cutters are of appreciable circumferential length so that their combined cutting contact with the wall of the well bore constitutes an appreciable arc of its circumference, shown in the present instance as nearly one-half the circumference of the well bore. By the construction as described vertical channels H are formed between the rows of cutters, and are of a cross-sectional area providing for passage of cuttings without liability of clogging the channels.

The cutters of each vertical row are ofiset longitudinally of the tool relative to the cutters of the other rows as shown at Fig. 1, with the vertical space between adjacent cutters of any one row equi-distantly divided by the cutters of the other rows; and the leading end N3 of each cutter of a row projects below the trailing end IQ of the vertically next adjacent cutter of that row of cutters which is next in advance in the direction of rotation of the tool, the direction of rotation being indicated by the arrow A at Fig. 1.

The cutters are adapted not for a mere swedging or scraping action forcing the formation radially outwardly to enlarge the bore, but are adapted to actually cut away the formation by a shearing action. For this purpose the under surface of cutter i5 slants upwardly toward the axis of the tool as shown at 2t, and the peripheral edge ill of the cutter slants downwardly from its leading end l8 to its trailing end l9 as shown at Fig. 1. The outer surface of the cutter slants radially inwardly and upwardly from the peripheral edge It toward the axis of the tool and may merge into the upper surface of the cutter which may in turn continue said slant so as to merge into the peripheral wall of sleeve 2. It will thus be seen that the cutter does not have a blunt surface contact with the formation, but that the slanting peripheral edge I6 is a relatively sharp cutting edge adapted for shearing out into the formation.

The cutting edge it preferably has a cutting point at its leading end for initiating a shearing cut into the formation, and for this purpose the leading end is of the cutter preferably slants radially outwardly toward the leading end of cutting edge It as shown at Fig. 2, and the outer and upper surfaces of the cutter in addition to slanting downwardly and outwardly. radially of the tool mag-"slant downwardly circumferentially of the tool and toward the leading end of cutting edge I6 as shown at 23 (Fig. 3), and the leading end I8 of the cutterpreferably slants upwardly and back toward the trailing end of the cutter from the lower edge of said leading end as shown at Fig. 1, in order to form a distinct cutting point 24 at the leading end of the cutter.

In order to maintain the shearing cut as initiated by the cutting point 24, the cutter preferahly has additional cutting points spaced rearwardly from the cutting point 24 along the circumferential length of the cutting edge It; and for this purpose the cutter has. vertical grooves 25 in its outer face, of a depth somewhat less than the radial width of the cutter and spaced along the circumferential length of the cutter. Each cutter is thus divided into a plurality of teeth comprising a leading tooth 26 and a plurality of successively trailing teeth 26 with the cutting edge is divided into a plurality of separate cutting edges Hi for the respective teeth 26-26. The plurality of cutting edges 56 define the general downward slant of cutting edge l6 toward the trailing end i9 of the cutter, but these cutting edges it are preferably substantially parallel and are inclined slightly to the general slant of cutting edge it as shown at Fig. 1, so that the leading end it of each of the trailing teeth 25 extends below the trailing end Is of the preceding tooth. The leading ends i8 of the trailing teeth preferably slant radially outwardly toward the leading ends of their cutting edges w as shown at Fig. 2, and the outer and upper surfaces of the trailing teeth may slant downwardly both radially and circumferentially of the tool and toward the leading ends of their cutting edges ic as shown at 23 (Fig. 3), and the leading ends Ill of the trailing teeth preferably slant upwardly and back toward the trailing ends of said teeth from the lower edges of said leading ends as shown at Fig. 1, in order to form cutting points M at the leading ends of the trailing teeth. The successively trailing cutting points 24-44 thus project vertically downwardly one below another sothat they are each adapted to dig into the formation and initiate a shearing out along their respective cutting edges 16 without the cutting point of a preceding tooth masking the cutting point of the next trailing tooth.

Any desired number of cutters it may be pro vided in each of the vertical rows of cutters, and a plurality of intermediate cutters of each vertical row, shown as cutters B, have a radial width whereby they are adapted to cut to gauge, and at least the upper cutter of each vertical row is slightly under gauge as shown at C for guiding the tool during withdrawal from the well bore, while a plurality of the lower cutters of each vertical row, shown at D, are preferably under gauge and of decreasing radial width toward the lower end of the tool for gradually enlarging the well bore to gauge as the tool is lowered in the well.

Lugs may project from the sleeve '2 below each row of cutters l5, with the lugs tapering downwardly and merging into the peripheral surface of the sleeve for guiding the tool into a well bore; and these guide lugs are preferably provided with circumferential grooves 3i affording relief for cuttings for preventing clogging of the col.

If desired cuttings may be washed away by providing downwardly opening ports 33 in the wall of mandrel 3, with the sleeve 2 having ports at communicating with the ports 33 but preferably. of larger diameter to prevent cutting-out of the ports. A part of the fluid in circulation bore 8 may thus be discharged through the ports which are preferably positioned in the channels ll between the circumferentially next adjacent vertical rows of cutters. 1

By arranging the teeth of each cutter circumferentially adjacent one another but appreciably circumferentially spacing the respective vertical rows of cutters, rather than equi-distantly spacing all of the teeth around the circumference of sleeve 2, the teeth are adapted for contact with the well bore throughout an appreciable arc of its circumference, but at the same time the vertical channels l1 between the circumferentially next adjacent rows of cutters are not so restricted as'to be liable to clog, but are of appreciable area for free passage of cuttings; and by arranging the teeth so that each tooth has a '1 cutting point projecting below the trailing end of the preceding tooth, each cutting point is adapted to dig into the formation, with its slanting cutting edge It then shearing away the formation, and the plurality of teeth making a continuous shearing cut around the entire circumference of the well bore and along an appreciable length of the bore.

I claim:

1. In a rotatable well reamer, a plurality of radially projecting cutting teeth relatively spaced around the entire circumference of the reamer, the end'of each tooth which is its leading end with relation to the direction of rotation of the reamer extending below the trailing end of the next preceding tooth, and the lower faces of the teeth slanting downwardly circlnnferentially of the reamer and toward the trailing ends of the teeth.

2. A rotatable well reamer having a radially projecting cutting tooth, the lower face of the tooth slanting downwardly circumferentially oi the reamer and toward the trailing end of the tooth and also slanting downwardly radially of the tooth to its outer periphery, whereby the outer peripheral lower edge of the tooth forms a relatively sharp shearing cutting edge.

3. A rotatable well reamer having a radially projecting cutting tooth, the leading'end of the tooth with relation to the direction of rotation of the reamer slanting circumferentially forwardly all the way to the outer periphery of the tooth, and the lower face of the tooth slanting downwardly circumferentially of the reamer and away from the leading end of the tooth, whereby the lower edge of the leading end of the tooth forms a relatively sharp cutting point at the outer periphery of the tooth with the lower face of the tooth forming a shearing cutting surface extending circumferentially rearwardly from said cutting point.

4. A rotatable well reamer having a radially projecting cutting tooth, the outer face of the tooth slanting radially outwardly and downwardly all the way to the outer peripheral lower edge of the tooth, and the lower face of the tooth slanting downwardly circumferentially of the reamer and away from the leading end of the tooth, whereby the outer peripheral lower edge of the tooth forms a relatively sharp shearing cutting edge.

5. A rotatable well reamer having a radially projecting cutting tooth, the outer face of the tooth slanting radially outwardly and downwardly all the way to the outer peripheral lower edge of the tooth, the lower face of the tooth slanting downwardly radially of the tooth to its outer periphery, and said lower face of the tooth slanting downwardly circumferentially of the reamer and away from the leading end of the tooth, whereby the outer peripheral lower edge of the tooth forms a relatively sharp shearing cutting edge.

6. In a rotatable well reamer, a plurality of radially projecting cutting teeth relatively spaced around the entire circumference of the reamer, the end of each tooth which is its leading end with relation to the direction of rotation of the reamer extending below the trailing end of the next preceding tooth, and the lower faces of the teeth slanting downwardly radially of the teeth to their outer peripheries.

7. In a rotatable well reamer, a plurality of radially projecting cutting teeth relatively spaced around the entire circumference of the reamer, the end of each tooth which is its leading end with relation to the direction of rotation of the reamer extending below the trailing end of the next preceding tooth, and the outer and lower faces of the teeth slanting downwardly radially of the teeth and meeting at relatively sharp cutting edges at the outer peripheral lower edges of the teeth.

8. In a rotatable well reamer, a plurality of radially projecting cutting teeth relatively spaced around the entire circumference of the reamer, the end of each tooth which is its leading end with relation to the direction of rotation of the reamer extending below the trailing end of the next preceding tooth, the outer and lower faces of the teeth slanting downwardly radially of the teeth and meeting at relatively sharp cutting edges at the outer peripheral lower edges of the teeth, and said cutting edges slanting downwardly circumferentially of the reamer and toward the trailing ends of the teeth, whereby the cutting edges are adapted for shearing engagement.

9. In a rotatabie well reamer, a plurality of radially projecting cutters appreciably circumferentially spaced from one another and each comprising a plurality of cutting teeth with the teeth of each cutter circumferentially spaced from one another a relatively slight distance, whereby the teeth of the plurality of cutters provide cutting contact throughout an appreciable arc of a circumference, with channels of appreciable size between circumferentially next adjacent cutters, the cutter teeth of the plurality of cutters being relatively spaced around the entire circumference of the reamer, with the lower faces of all of the teeth slanting downwardly toward their ends which are the trailing ends with relation to the direction of rotation of the reamer.

10. In a rotatable well reamer, a plurality of radially projecting cutters appreciably circumferentially spaced from one another and each comprising a plurality of cutting teeth with the teeth of each cutter circumferentially spaced from one another a relatively slight distance, whereby the teeth of the plurality of cutters provide cutting contact throughout an appreciable are of a circumference, with channels of appreciable size between circumferentially next adjacent cutters, the cutter teeth of the plurality of cutters being relatively spaced around the entire circumference of the reamer, with the end of each tooth which is its leading end with relation to the direction of rotation of the reamer below the trailing end of the next preceding tooth.

11. In a rotatable well reamer, a plurality of radially projecting cutting teeth relatively spaced around the entire circumference of the reamer, the lower facesof all of the teeth slanting downwardly toward their ends which are the trailing ends with relation to the direction of rotation of the reamer.

12. A rotatable well reamer having a radially projecting cutting tooth, the lower face of the tooth slanting downwardly circumferentially of the reamer toward the trailing end of the tooth, and the leading end of the tooth slanting upwardly from its lower edge and rearwardly toward the trailing end of the tooth, whereby the lower edge of the leading end of the tooth forms a relatively sharp cutting edge with the lower face of the tooth forming a shearing cutting surface extending circumferentially rearwardly from said cutting edge.

13. In a rotatable well reamer, a plurality of radially projecting cutting teeth relatively spaced around the entire circumference of the reamer, the end of each tooth which is its leading end with relation to the direction of rotation of the reamer extending below the trailing end of the next preceding tooth, and the outer face of each tooth slanting radially outwardly and downwardly all the way to the outer peripheral lower edge of the tooth so that the teeth form relatively sharp cutting edges.

14. In a rotatable well reamer, a plurality of radially projecting cutting teeth relatively spaced around the entire circumference of the reamer, the end of each tooth which is its leading end with relation to the direction of rotation of the reamer extending below the trailing end of the next preceding tooth, and the leading end of each tooth slanting upwardly from its lower edge and rearwardly toward the trailing end of the tooth, whereby the lower edges of the leading ends of the teeth form relatively sharp cutting edges.

JOHN W. MACCLATCHIE.