U.S. patent number 3,765,494 [Application Number 05/246,293] was granted by the patent office on 1973-10-16 for circulating sleeve.
Invention is credited to Fred S. Kielman, Jr..
United States Patent |
3,765,494 |
Kielman, Jr. |
October 16, 1973 |
CIRCULATING SLEEVE
Abstract
In a drilling system, a subassembly provides a means for seating
an instrument housing in the drill string during a drilling
operation and for permitting a normal flow of drilling fluids
around the instrument housing. The seat also provides means for
orienting the instrument housing in a predetermined position
relative to a portion of the drill system.
Inventors: |
Kielman, Jr.; Fred S. (Sugar
Land, TX) |
Family
ID: |
22930055 |
Appl.
No.: |
05/246,293 |
Filed: |
April 21, 1972 |
Current U.S.
Class: |
175/320;
175/45 |
Current CPC
Class: |
E21B
23/02 (20130101); E21B 17/00 (20130101); E21B
47/01 (20130101) |
Current International
Class: |
E21B
23/02 (20060101); E21B 23/00 (20060101); E21B
47/00 (20060101); E21B 47/01 (20060101); E21B
17/00 (20060101); E21b 017/00 () |
Field of
Search: |
;175/4.51,44,45,73,75,61,320,324 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Brown; David H.
Claims
What is claimed is:
1. In a drilling system utilizing a hollow conduit for carrying a
drilling fluid means for seating an instrument housing within the
conduit while performing a drilling operation, which means
includes: a seat formed within the bore of said conduit, a sleeve
sized for reception within the bore of said conduit, shoulder means
on one end of said sleeve for providing a mating reception of said
sleeve within said seat, said shoulder means being sized for close
fitting reception within said conduit, a plurality of longitudinal
ribs on said sleeve extending above said shoulder means and key
means extending inwardly from said sleeve for orienting an
instrument housing.
2. The apparatus of claim 1 and further including a transverse
opening extending through one of said ribs and sleeve for receiving
said key means.
3. The apparatus of claim 1 and further including means of locking
said sleeve against relative movement with said conduit.
4. The apparatus of claim 3 wherein said locking means extends
through the wall of said conduit and further including seal means
on said shoulder arranged to be positioned above and below said
locking means when said sleeve is seated in said conduit.
5. A circulating sleeve for seating and orienting an instrument
housing within the bore of a drill pipe during a drilling operation
and arranged to permit the flow of fluids through the drill pipe
when an instrument housing is positioned therein, comprising: a
sleeve for reception within the bore of the pipe, and having a
cylindrical portion with longitudinal ribs formed thereon for
engaging the bore of the pipe and maintain said cylindrical portion
in a spaced position from said bore; a shoulder formed on said
sleeve for engaging a seat in the pipe; key means extending from
the wall of said cylindrical portion into its bore for engaging a
portion of the instrument housing to orient the housing with
respect to said sleeve; and means on said sleeve for receiving a
member extending from the wall of the pipe for holding said sleeve
against rotation relative to the pipe.
Description
BACKGROUND OF THE INVENTION
The present invention pertains to a circulating sleeve and more
particularly to an apparatus for orienting an instrument within a
drill string and providing for the circulation of fluid about the
instrument to permit drilling when an instrument is seated
therein.
When drilling boreholes in the earth's surface it is often
desirable for various reasons to deviate the holes from a vertical
course through the earth formations. The term "directional
drilling" is applied to such operations. One example of the use of
such directional drilling operations is found in the drilling of
oil wells from offshore platforms. It is a common practice to build
large drilling platforms which are permanently secured to the ocean
floor and from which a multiplicity of wells are drilled. Because
of the number of wells which are drilled from a single platform, it
is necessary to drill the holes laterally away from the platform so
that earth formations containing petroleum reservoirs may be
penetrated at distances laterally spaced from the platform. This
procedure permits production from as great an area as possible from
a single platform. It is easily understood how important the
maintenance of direction and dip of such boreholes is in order to
penetrate particular formations at predetermined depths and thereby
intersect the desired petroleum reservoirs.
One technique for obtaining such information as to the direction of
a borehole is to cease drilling and run a surveying instrument into
the drill pipe on a wire line. Alternatively, the instrument may be
go-deviled to the bottom of the drill pipe. The instrument is
oriented with respect to the drill stem by means of a "muleshoe"
sub located at the lower end of the drill stem. The "muleshoe" is
simply a device for capturing the tool and orienting the tool in a
predetermined radial direction with respect to a position on the
drill stem. For example, the drill stem normally used in such a
directional drilling operation includes what is normally termed a
"bent sub," at its lower end which places a bend in the lower end
of the stem and thereby permits angular deviation of the drill bit.
The "muleshoe" is normally oriented with respect to the "bent sub."
This in turn orients the instrument which is being positioned in
the lower end of the drill stem. This series of orientation
procedures provides a correlation between the direction in which
the drill bit is angled and the directional alignment of the survey
instrument. After the survey instrument is operated to generate a
record, generally be means of a timing mechanism, the tool is
retrieved to the surface by means of a wire line. The record is
then processed and examined to determine the direction in which the
hole is being drilled.
More recently, techniques have been developed for passing an
instrument into the drill stem by means of a conductor cable to
provide continuous directional information to the surface during
the drilling operation. This technique also utilizes the method
described above of locating the instrument within a "muleshoe"
which in turn is oriented in a particular radial direction with
respect to a "bent sub" in the drill string. Thus, the information
which is received at the surface indicative of the direction in
which the survey instrument is positioned is correlated with the
direction that the bit is angled.
It is common in such directional drilling operations to use a mud
motor or turbine for rotating the drill within the borehole. Such a
motor or turbine requires the continuous circulation of drilling
fluids through the motor to provide the power for turning the
drill. Therefore, it is essential that a constant flow of drilling
fluids be maintained through the system even while an instrument is
positioned within the drill stem.
It is therefore an object of the present invention to provide a new
and improved circulating sub for receiving an orientation
instrument within a drill string.
SUMMARY OF THE INVENTION
With this and other objects in view, the present invention
contemplates a drill pipe having a recessed portion therein forming
a seat within the bore of the pipe. A sleeve which is sized for
reception within the recessed portion has a shoulder which when
received within the recess mates with the seat. A plurality of
longitudinal ribs are formed on the sleeve and extend upwardly from
the shoulder. Means extend inwardly from the sleeve for engaging a
mating surface on an instrument housing to thereby locate the
instrument in a predetermined manner within the sleeve.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing of the lower portion of a drill
string, including a rotating bit sub and mud motor together with an
apparatus for receiving and positioning an instrument in the drill
pipe in accordance with the present invention;
FIG. 2 is a detailed sectional view of the positioning and
orienting apparatus; and
FIG. 3 is a cross sectional view taken along lines 3--3 of FIG.
2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1 of the drawings, the lower end of the
drill stem is shown including a drill collar 27 and a muleshoe
orienting sub 28. A bent sub 29, mud motor or turbine 31, and a
rotating bit sub 32 are positioned below the orienting sub. An
instrument which for the purpose of this disclosure shall be
referred to as an orienting tool 33, is shown positioned within the
interior bore of the drill collar and is connected at its upper end
with a conductor cable 26 extending to the surface. Typically, the
conductor cable would extend through a line wiper at the surface
and be taken up on a motor driven drum which permits its playout
and take up during operations. The line wiper is constructed to
seal off well pressure at the well head during line operations in
the drill pipe.
Referring again to the lower end of the drill stem, a muleshoe
sleeve 34 is shown positioned within the muleshoe orienting sub 28
and is oriented therein in a predetermined fashion. The sleeve 34
is held in the predetermined position within the sub by means of a
screw or the like 36 extending through the side wall of the sub 28.
The muleshoe sleeve 34 is shown having a key 37 positioned in its
sidewall and extending inwardly into the sleeve bore. The muleshoe
and its key are normally oriented directionally with respect to the
bent sub and thus with respect to the drill bit which derives its
direction of inclination by means of the bent sub. This
predetermined alignment of the muleshoe key with respect to the
bent sub is convenient for purposes of determining the original
orientation of the drill with respect to surface indications of
tool direction and thereafter for making compensating changes in
drilling direction. The muleshoe sleeve or circulating sleeve as it
will be hereinafter referred to, may be utilized to positionally
locate various types of instruments within a drill pipe; however,
since one of its primary uses is for locating directional drilling
orienting instruments this disclosure will continue to use such an
instrument as an example.
The orienting tool 33 which is shown schematically in FIG. 1
includes a muleshoe 39 which is secured to the lower end of the
tool string. The muleshoe includes a protruding shaft or stinger 41
having a tapered end 42 (see FIG. 2) for guiding the stinger into
the muleshoe sleeve 34. A shoulder 43 extends spirally around
opposite sides of the stinger, meeting at a pointed terminus 44, to
form a camming surface. On the opposite side of the tool from the
terminus 44, the spiral shoulders 43 meet to form a short
longitudinally extending slot 45. The slot 45 is sized to receive
the inwardly extending key 37 on the muleshoe sleeve 34 when the
tool 33 is positioned in the drill pipe. The tool string 33 further
includes a muleshoe adjuster which permits rotation of the muleshoe
39 relative to the tool string 33. The adjuster includes includes
mating portions (not shown) between the muleshoe and tool string to
permit relative rotation therebetween, and a locking collar 35 for
securing the tool string and muleshoe in a fixed rotational
position. Greater detail of the muleshoe and its functional use
with an orienting tool is shown in co-pending U.S. Pat. application
Ser. No. 86,877, now U.S. Pat. No. 3,718,194, which is assigned to
same assignor as the present application.
Referring next to FIG. 2 of the drawings, the circulating sleeve 34
and its cooperative relationship with the sub 28 is shown in
greater detail. Sub 28 has a recessed bore portion 46 with a
tapered seat 47 at its lower end. The circulating sleeve 34 is
shown positioned within the sub 28. The sleeve 34 has a body
portion 49 with longitudinal ribs 48 extending outwardly therefrom
into contact with the recessed inner bore portion 46 of the sub 28.
The longitudinal ribs 48 extend downwardly below the lower end of
the body portion 49. A cylindrical sleeve 51 is formed at the
bottom end of the longitudinal ribs. Tapered top and bottom
surfaces 52 and 53, respectively, are formed on the sleeve 51. The
lower surface 53 is arranged to matingly seat on the tapered
surface 47 of the recessed bore 46 in sub 28. Upper and lower
peripheral grooves 54 and 56, respectively, are formed on the
surface of the exterior wall of sleeve 51, and are sized to receive
O-ring seals therein. Another peripheral groove 57 is formed
between the grooves 54 and 56 in the outer wall of the sleeve 51
for receiving an inwardly extending end portion of a set screw 36.
The body portion 49 of the circulating sleeve 34 and one of the
longitudinal ribs 48 have an aligned opening formed through the rib
and body portion for receiving the key 37. The key 37 has an
enlarged shoulder portion 61 formed thereon which abuts a
complimentary shoulder formed in the rib opening.
In the operation of the system described herein the following
method is employed: the circulating sleeve 34 is inserted into the
upper end of sub 28 until the lower tapered surface 53 on sleeve 51
is matingly seated on tapered surface 47 within the bore of sub 28.
The circulating sleeve is then rotated within the bore of sub 28
until the key 37 which extends inwardly from the sleeve is
positioned in accordance with a predetermined arrangement to permit
orientation with respect to a portion of the drill stem. Normally,
the predetermined alignment of the key 37 is in some relationship
with the bent sub 29 so that it is known that the muleshoe key 37
is pointing in a particular direction with respect to that in which
the drill is pointing. This arrangement provides means for
determining, by means of an orienting instrument to be located
within the muleshoe sub in what direction the drilling operation is
being conducted. In any event, after the key 37 and the circulating
sub has been oriented within the sub 28, set screws 36 are rotated
until they extend inwardly into the groove 57 on lower sleeve 51
and tightened therein to hole the sleeve in a fixed relationship
with the sub 28 and thereby prevent its rotation within the sub.
Next, the sub 28 is made up in the drill string and the drill
string is lowered into the wellbore for purposes of performing the
drilling operation.
Thereafter, when it is desired to lower an instrument into the
drill stem by means of the cable 26 shown in FIG. 1, such
instrument is lowered until the muleshoe stinger 41 extends into
the circulating sub 34 whereupon the spiral camming surface 43
thereon engages the key 37 and produces a camming action to rotate
the muleshoe until the longitudinal slot 45 of the muleshoe drips
over the key 37. The procedure thus far described permits the
instrument housing located above the muleshoe to be radially
positioned within the drill stem in a predetermined manner. The
arrangement of the circulating sub, seat and muleshoe permits the
circulation of drilling fluids through the drill stem even when the
instrument and muleshoe are seated within the drill string. This is
provided by means of the annular spaces between the longitudinal
ribs 48 and between the sleeve 51 and the lower end of the
muleshoe. The path of such fluid circulation is shown by the arrows
in FIG. 2.
With the circulating sub described herein the volume of fluid that
may be circulated through the system is sufficient to drive the mud
motor or turbine during drilling operations while permitting the
continuous use of an orienting instrument.
Wile a particular embodiment of the present invention has been
shown and described, it is apparent that changes and modifications
may be made without departing from this invention in its broader
aspects and therefore the aim in the appended claims is to cover
all such changes and modifications as which fall within the true
spirit and scope of this invention.
* * * * *