CN213540285U - Tail pipe column - Google Patents

Abstract

The utility model relates to a tail pipe column, which comprises a plurality of sections of mutually connected 5-inch tail pipes; a stop collar is arranged in one section of 5-inch tail pipe; the lower part of the stop collar is provided with a floating collar; a plurality of through holes are formed in a tail pipe of 5 inches of the lower section of the floating hoop so as to form a perforated pipe; artificial cement shoes are arranged at the lower ends of the perforated pipes; the lower part of the artificial cement shoe is provided with the cement umbrella, and the tail pipe column cannot be driven into the designed depth for a 7-inch production tail pipe, so that follow-up remedial measures are provided, and the production effect of an oil field is guaranteed. The original well structure is extended downwards continuously, the flexibility of engineering design is improved, one layer of casing is added, and the operation risk of a complex stratum is reduced. The technical bottleneck of unconventional well cementation with small tail pipes and matched small-hole well drilling operation is broken through, important reference significance is provided for subsequent similar operation, and the well summarizing and application of the 3-3/4-inch small-hole well drilling technology is performed.

Description

Tail pipe column

Technical Field

The utility model relates to an oil and gas bores well completion technical field, especially relates to tail pipe post.

Background

In a drilling and completion process system, a well structure design is usually an important part in a drilling engineering design, and a common marine casing program can be generally divided into: the production casing of the reservoir is often a tail pipe, and because the implementation difficulty of small-tail-pipe well cementation and small-size drilling technologies is high, the minimum-size tail pipe commonly used in marine drilling is 7 inches, and the minimum borehole size is 6 inches, the continuous downward extension of a well body structure is limited. The 7-inch production tail pipe is usually required to be lowered to a deeper stratum, the lowering section is longer, the interlayer of the deep stratum is more, the well condition is complex, and the 7-inch production tail pipe has the risk of not being in place, so that the designed sealing section (such as a water layer and the like) can not be sealed, and the production yield of an oil well is seriously influenced.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model lies in that, a tail pipe column is provided.

The utility model provides a technical scheme that its technical problem adopted is: constructing a liner string comprising a plurality of sections of interconnected 5 inch liners; a stop collar is arranged in one section of 5-inch tail pipe; the lower part of the stop collar is provided with a floating collar; a plurality of through holes are formed in a tail pipe of 5 inches of the lower section of the floating hoop so as to form a perforated pipe; artificial cement shoes are arranged at the lower ends of the perforated pipes; the lower part of the artificial cement shoe is provided with a cement umbrella.

Preferably, a 2-section 5-inch tail pipe is arranged between the stop collar and the float collar.

Preferably, 3 rows of perforated pipe walls are uniformly distributed at intervals, and each row is provided with 2 through holes.

Preferably, the thickness of the artificial cement shoe is 4 meters.

Preferably, the cement umbrellas are arranged in two sets at intervals.

Preferably, the topmost 5 inch tailpipe is provided with a tailpipe hanger on its outer periphery.

Preferably, the bottom end of the tail pipe column is provided with a tail pipe floating shoe.

Preferably, the tail pipe float shoe is a valve body without a check valve inside.

Implement the utility model discloses following beneficial effect has: aiming at the situation that the 7-inch production tail pipe cannot be driven into the designed depth, the follow-up remedial measure is provided, and the production effect of the oil field is guaranteed. The original well body structure is extended downwards continuously, the flexibility of engineering design is improved, one layer of casing is added, the operation risk of a complex stratum is reduced, the technical bottleneck of unconventional well cementation of small tail pipes and matched small well drilling operation is broken through, important reference significance is provided for subsequent similar operation, and the well drilling technology of the small well with the diameter of 3-3/4 inches is summarized and applied well.

Drawings

The invention will be further explained with reference to the drawings and examples, wherein:

fig. 1 is a schematic structural diagram of the tail pipe column of the present invention.

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "upper", "lower", "left", "right", "longitudinal", "horizontal", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail", etc. are configured and operated in specific directions based on the directions or positional relationships shown in the drawings, and are only for convenience of describing the present invention, but do not indicate that the device or element referred to must have a specific direction, and thus, should not be construed as limiting the present invention.

It is also noted that, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," "disposed," and the like are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. When an element is referred to as being "on" or "under" another element, it can be "directly" or "indirectly" on the other element or intervening elements may also be present. The terms "first", "second", "third", etc. are only for convenience in describing the present technical solution, and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated, whereby the features defined as "first", "second", "third", etc. may explicitly or implicitly include one or more of such features. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

As shown in fig. 1, the tailpipe column of the present invention is characterized by comprising a plurality of sections of 5 inch tailpipes connected to each other, such as 5 inch tailpipes 1, 5 inch tailpipes 5, 5 inch tailpipes 6, 5 inch tailpipes 8, 5 inch tailpipes 10, 5 inch tailpipes 12, etc. It will be appreciated that the 5 inch tailpipe is comprised of a large number of sections, with the overall tailpipe string being up to several hundred meters.

Furthermore, a stop collar 4 is arranged in one 5-inch tail pipe, a floating collar 7 is arranged at the lower part of the stop collar 4, and 2 sections of 5-inch tail pipes, such as 5-inch tail pipes 5 and 5-inch tail pipes 6 in the figure, are arranged between the stop collar 4 and the floating collar 7. The stop collar 4 can also be called a bumping coupling in the field, 2 tail pipes are kept between the stop collar 4 and the float collar 7, the stop collar 4 can be prevented from being out of work, and in case of no bumping, the stop collar can be replaced into one more casing inner volume (the well is finally bumped normally).

The next section 5 inches tail pipe of this 5 inches tail pipes that float collar 7 belonged to is equipped with a plurality of through-holes in order to form perforated pipe 8, and is concrete, and 3 rows of interval equipartitions of 8 pipe walls of this perforated pipe, every row sets up 2 through-holes, both satisfied the cement circulation passageway, do not seriously influence tail pipe column strength structure again.

The artificial cement shoes 9 are arranged at the lower ends of the perforated pipes 8, the thickness of the artificial cement shoes 9 is 4 meters, and cement can be prevented from sinking along the inner part of the tail pipe to influence the production of a cement section.

The lower part of the artificial cement shoe 9 is provided with cement umbrellas, specifically, the cement umbrellas are two sets of cement umbrellas 11 arranged on a 5-inch tail pipe 10 and two sets of cement umbrellas 13 arranged on a 5-inch tail pipe 12 at intervals. Furthermore, two sets of cement umbrellas are arranged at the lower end of the cement shoe 9 and enter a 6-inch open hole section, the cement umbrella 13 at the lower end enters about 12m of the 6-inch open hole section, and the cement umbrella 11 at the upper end enters about 8m of the 6-inch open hole section, so that the cement annulus is effectively prevented from sinking.

Further, a tail pipe hanger 2 is arranged on the periphery of the 5-inch tail pipe at the topmost end. The tail pipe hanger 2 is provided with a tail pipe shoe 3 at the periphery, and actually, a plurality of 5-inch tail pipes can be arranged between the tail pipe hanger 2 and the stop collar 4.

Further, a tail pipe float shoe 14 is arranged at the bottom end of the tail pipe column. The 5 inch tailpipe float 14 is a valve body without a check valve inside. Specifically, a floating shoe is installed at the bottom of the well, an internal check valve is removed, the tail pipe floating shoe 14 plays a guiding role, a tail pipe can be conveniently and smoothly put in place, drilling is convenient in the process of drifting of a rear small well, and an oil layer channel is opened.

In an actual application scene, compared with a conventional borehole, the 3-3/4' slim hole drilling technology has the advantages that small drilling tools belong to micro-couplings and cannot be used for buckling an elevator, a lifting wire or a lifting short section is required to be used in the connection process of each small drilling tool, and a safety slip is required to be drilled for each small drilling tool; the 2-7/8 'drill pipe and 3-1/8' drill collar are small in buckling torque, and in the buckling process, chain tongs are used for buckling, and a special small-size tong is used for fastening. In the drilling process, the torque is strictly limited, and the joint buckle is prevented from being twisted and exploded; the drilling tool is flexible in rigidity and small in annular space, drilling pressure and discharge capacity need to be strictly controlled during drilling, the phenomena of bending of the drilling tool and sudden rising of annular pressure consumption are warned, meanwhile, when a cement plug and a sleeve metal accessory are drilled, torque is easy to be poor, a pump is easy to be held back, and downhole accidents such as drilling jamming are avoided.

The main technical points of the application of the tail pipe column are as follows:

(1) the usage amount of the centralizer is reduced to increase the friction resistance of the 5-inch tail pipe section, so that the judgment of the unhooking of the tail pipe hanger is facilitated; if the hanging weight change is not clear, the judgment of the hands-off display can be carried out, and the judgment can also be carried out through the torque change, if the hands-off is difficult or difficult to judge, the mechanical hands-off can be carried out again after the well cementation is finished, and then the setting is carried out;

(2) reasonably designing a pipe column, changing the previous well cementation operation mode, connecting a section of blind pipe for blocking the on-off circulation in the pipe at the lower end of the pipe column, and connecting a perforating pipe at the upper part of the blind pipe, wherein during the well cementation, cement returns upwards through the perforating position of the perforating pipe, and in order to avoid that a 6-inch well is excited too much by fluid passing through holes, the perforating position is recommended to be at least 5-8 meters away from the 6-inch well;

(3) in order to prevent the annular cement from sinking, double cement umbrellas are additionally arranged outside the pipe column; in order to fully play the role of the cement parachute, the cement parachute enters the 6-inch well hole for more than 5 meters;

(4) the seawater is used for displacement, the pressure difference between the inside and the outside of the pipe is reduced, the pressure can be obviously observed when the large and the small rubber plugs are sheared, and the internal volume of the drill pipe is accurately measured according to the displacement quantity of the rubber plugs during shearing;

(5) a well cementation pump is used for replacement, so that the problem of pump efficiency is avoided, and the phenomenon of 'replacement of air' or 'no pressure collision' is avoided;

(6) the double-coagulation cement slurry is used, the tail slurry is quick-setting cement slurry, the first slurry is slow-setting cement slurry, the excessive thickening time of the cement slurry is well controlled, and the first slurry and the tail slurry meet the 'right-angle thickening'.

The tail pipe column can not be driven into the designed depth for a 7-inch production tail pipe, provides subsequent remedial measures and guarantees the production effect of an oil field. The original well structure is extended downwards continuously, and the flexibility of engineering design is improved. And a layer of sleeve is additionally arranged, so that the operation risk of a complex stratum is reduced. The technical bottleneck of unconventional well cementation with small tail pipes and matched small well drilling operation is broken through, and important reference significance is provided for subsequent similar operation. Well summarized application was made to 3-3/4 inch slim hole drilling technology.

It is to be understood that the foregoing examples merely represent preferred embodiments of the present invention, and that the description thereof is more specific and detailed, but not intended to limit the scope of the invention; it should be noted that, for those skilled in the art, the above technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention; therefore, all changes and modifications that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims (8)

1. A tailpipe string comprising a plurality of sections of 5 inch tailpipes connected to one another; a stop collar is arranged in one section of 5-inch tail pipe; the lower part of the stop collar is provided with a floating collar; a plurality of through holes are formed in a tail pipe of 5 inches of the lower section of the floating hoop so as to form a perforated pipe; artificial cement shoes are arranged at the lower ends of the perforated pipes; the lower part of the artificial cement shoe is provided with a cement umbrella.

2. The tailpipe string according to claim 1, wherein 2-joint 5 inch tailpipes are provided between the stop collar and the float collar.

3. The tailpipe post according to claim 1, wherein the walls of the perforated pipe are spaced in 3 rows of 2 through holes.

4. The tailpipe post according to claim 1, wherein the thickness of the artificial cement shoe is 4 meters.

5. A tailpiece according to claim 1, wherein the cement parachute is provided in two spaced apart sets.

6. The tailpipe post according to claim 1, wherein the top-most 5 inch tailpipe is provided with a tailpipe hanger around its periphery.

7. The tailpipe stem according to claim 1, wherein a tailpipe float shoe is provided at the bottom end of the tailpipe stem.

8. The liner string according to claim 7, wherein the liner float is a valve body without a check valve inside.

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