SU1735570A1 - Blowout preventer - Google Patents

Abstract

The invention relates to oil field equipment and is intended to seal a mouth when drilling wells from which liquid or gaseous fluid is expected to be released. The purpose of the invention is to improve the reliability of the preventer during the pacing of the drill string. The preventor includes a housing in which staged dies are placed, a U-shaped section of the yoke and a mechanism for their drive in the form of a self-centering turning chuck. Dies and cages are made with rubber elements. In this case, the thickness of one sealing element is 1.5-2.0 times greater than the other sealing element of the clip. The step plate is made with a vertical groove in which the protrusion of the clip is placed. The base of the housing is made with annular projections of triangular cross section with rounded tops, interacting with sealing elements during sealing the well. 7 il. (L

Description

The invention relates to the drilling of wells from which a release of liquid or gaseous fluid is expected.

Known preventer, in which the cartridge is used as a drive and two-stage inseparable dies.

The drawbacks of the invention are that the undivided basement and tube dies work in different conditions: the tube interacts with the column tubes, with the untreated surface (when the string is pushed, they wear out quickly and are replaced), the socles interact with the cleaned surface of the base and wear out significantly in 5-10 times - slower.

As a result of uneven wear of the plates, the conditions for their interaction with sealing elements change: the preventer base and the pipe string.

Sealing of the column is impaired. In order to restore tightness between the tube plates and the column, it is necessary to apply additional pressure to the base plates, which over time is accompanied by overstretching of their lining until its physical properties are violated, therefore it is inevitable to replace both of the plates that are interlocked, despite the fact that The basements are quite suitable for further use, since under the described conditions their durability is 5–10 times longer than the pipe ones.

The line separating the plinth and pipe rams runs below the horizon.

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talny axis of the cam chuck, the image of the eccentricity of a significant size As a result, when the column is sealed, there are conditions for cam transfer in its guides, i.e. in the grooves of the body of the cartridge case.

When the die teeth are closed, a part of the chuck jaws, carrying the dies on it, emerges from the guide slots of the housing into its passage opening and smoothly sloped. When the plates are retracted, the slurry enters the initial position in the cartridge case, where the spur-pinion and gear-and-gear gears of the cartridge are located, which leads to jamming, jamming, and durability reduction.

The possibility of slagging is accompanied by a reduction in the range of application of the preventer — only within the limits of work in a low-acclaimed or unfilled environment.

The cartridge is placed in a firmly-tight case (the diameter of which is significantly larger than the diameter of the cartridge), is exposed to the downhole environment, as a result of which it is subjected to meaningless damage and has dimensions and weight that are significantly larger than those in which it can be accommodated during the reconstruction of the case and its connection with the cartridge .

The purpose of the invention is to increase the reliability of the preventer.

The goal is achieved by creating base and tube dies of this design and such conditions of their use, which would ensure the possibility of their operation to normal wear; limiting the eccentricity between the calculated line of the cam teeth and the plane passing between the base and pipe dies; exception of the possibility of sludge getting into the cavity of the cartridge case; extending the range of application of the preventer. including downhole medium of any degree of occlusion; a change in the pattern of docking of the cartridge with the body, a reduction in the size and weight of the preventer, an improvement in the working conditions of the cartridge; expanding the range of pressing the dies to the base as the tube dies wear out.

The essence of the proposed invention is that having preserved the traditional cross-sectional profile of the cam gear, its teeth and the firm dimensions of these elements without change, under the frontal end facing the pipe string, the combined but structurally separate planted — the bottom base is monolithic with the cam and her

top removable - pipe dies lined with sealing material. Moreover, the base plate is together with a C-shaped adapter (from the diameter of

to the diameter of the column), monolithic with a toothed rack cam. The upper edge of this die is raised to the lower plane of the cam rack. On the C-shaped adapter directly to the cam rack

and in its vertical grooves a removable tubular die-arcuate cradle with a lining, which is located opposite the cam end, is planted, i.e. with zero eccentricity and firmly fixed

spikes into the grooves of the toothed rack bolts to the transitional C-shaped element of the socle plate, adjacent to the frontal - the bottom side of the body of the cartridge. The outer sides of the U-shaped part of the tube die, on three sides enclosing a cam rail, slidably mounted in the guide grooves of the cartridge body, studded with a cam and sitting on a movable gear rack, are three-fold and have been worked out seal with the body of the cartridge in statics and kinematics - with a closed and open fan. Lathe chuck does not fit in

the body and is joined to it by the front side, as a result of which the dimensions and mass of the preventer are significantly reduced, and the transportability increases. On the outer surface of the socle, which interacts with the socle dies, a labyrinth cut is formed from concentrically arranged turns with rounded tops.

FIG. 1 and 1.1 shows a preventer, vertical section; in fig. 2 - plate with open preventer, top view; in fig. 3 shows a section BB in FIG. 2; in fig. 4 - plate with closed preventer, top view; in fig. 5 shows section B-3 in FIG. 1.1; in fig. 6 a section of YYY in FIG. 1.1; in fig. 7 is a fragment of the docking of the die case with the body of the cartridge.

In the drawing, the conventions / 1, f-2, etc., are used for the most accurate coordination of the elements.

The preventer is assembled from commercially available and separately manufactured parts. The standard, three-jaw, self-centering lathe chuck belongs to the purchased ones. Perhaps the use of two or four-round cartridges. The cartridge is selected taking into account that its through hole / 1 (Fig. 1 and 4) ensures the free passage of the bit; the cam stroke must be equal

no less than the radius of the bore; the force developed by the cams must ensure that the dies are properly pressed against the column; The cog racks should have a bending strength that ensures the perception of axial forces arising during the pacing of the column; have corrosion resistance; cam movement is synchronized with high precision.

The cartridge is used as a drive mechanism for radial movement of the cam racks provided with dies and pressed against the preventer base and the column. Cartridges supplied for sale are supplied with two types of cams: monolithic, in which the toothed rack and the cams themselves are a single piece, and separate, in which the separate rack and cams are blocked by spikes and screws. Both options are acceptable. However, in monolithic cams, the rack and pinion remains unchanged, and the cams themselves in the process of their manufacture are replaced by arcuate elements, for example, with rubber lining, which together form the basement dies of the preventer. In the case of cam gear racks of a separate construction, instead of the cams themselves, arcuate elements with the same parameters as the described monolithic ones forming basement dies interacting with the preventer base are attached to the standard rack.

When using a three-jaw chuck, each die bends around the base or column at an angle of 120 °. With a four-cam - at 90 °. With two-cam - 180 °. Manufactured includes a crankcase containing in its cavity the said dies.

The preventer includes a housing 1.0 of the cartridge with its housing 1.1, radial grooves 1.2 and seals 1.3 in them (shown conventionally), grooves 1.4 for dies, slots 1.5 for driving gears, and coupling groove 1.6. An annular disk 2.0 with helical gearing 2.1 on its lower side and teeth 2.2 of a bevel gear on the top is fitted into the crankcase 1.1. In the 1.5 sockets, the pinion gears 3.0 and the spacing hub 4.0 are seated, locked and sealed, and closed with the flange 5.0 on the studs 6.0. A special profile of gear racks 7.0 with 7.1 teeth on their upper side, facing into the crankcase 1.1 1.1 response spirals 2.1 and interacting with it, and arc-shaped elements 7.2 with lining 7.3, forming dies basement

on the underside of the toothed rack facing the die case. Moreover, the upper edge of this plate passes in the same plane with the lower plane of the rail 7.0. At the end of each gear

The slats 7.0 facing the column are formed with vertical grooves 7.4 (FIG. 4), in which spikes 8.0 are pressed into pipe or blind 8.1 dies with lining 8.2, which are bolts 9.0, nuts 10.0 and adjustable

0 with pins 11.0 are firmly tightly interlocked with the upper C-shaped part of the socle plates 7.2 - 7.3. The purpose of the separate implementation of the lower basement 7.2-7.3 and the upper tube 8.1-8.2 dies is

5 providing the possibility of inserting the toothed racks 7.0-7.1 with the lower plinth plates 7.2-7.3 into the slots 1.2 of the body of the cartridge 1.0, ensuring the possibility of separate replacement of the lining of the socle and pipe

0 or deaf dies with different durability, which are objectively determined by different conditions of their work (the tube pipes interact with the untreated surface of the walking column, and the socle ones with

5 with a cleanly machined plinth surface), and allowing the maximum rise of the upper edge of the plinth die to the lower plane of the rack, which at the same time

0 maximal lifting of a pipe or hollow plate, which favorably influences the reduction of the tilt of the toothed rack when sealing a well.

To the front of the cartridge, the spotting is mounted on the undercut 1.6 and fixed

5 crankcase 12.0 with a cavity 12.1 in which socle plates 7.2-7.3 are enclosed. On the bottom of the crankcase 12.0 there is a base 12.2 with labyrinth rings 12.3 rounded at the tops, channels for flushing

0 media 12.4 and threaded holes for studs 12.5.

Carter 12.0 to body 1.0 of the cartridge is fastened with screws 13.0.

Studs 14.0 are fitted in flange 5.0,

5 intended for planting the next wellbore at the wellhead. In the aperture of the preventer - a column of pipes 15.0.

The preventer works as follows.

The preventer operates statically or rotationally on a subclotte. By rotating one of the three leading gears 3.0 clockwise, rotation is reported.

5 an annular disk 2.0, which with its spiral 2.1 moves the toothed racks 7.0 with stepped dies (ground and pipe or blind) from the position

shown in FIG. 1, left side to the main axis of the preventer. Moving the dice back is achieved by turning gear 3.0 counterclockwise. If there are 15.0 stepped dies in the preventer of the column: the basement approaches the base 12.2 with labyrinth cutting 12.3, and the tube ones - the column 15.0 and seals the annular gap between the borehole walls and the column (Fig. 1.1, right side). In this case, the lining of the side surfaces of the plates of the same name and the horizontal lintel 7.3.1, enclosed between them, intersect along the perimeter of their joining. In such a position of the plates, the possibility of the wellbore medium entering the cavity, the preventer mechanism and its passage opening is completely excluded. As the lining of the tube dies, which is objectively accompanied by the pacing of the column, deteriorates, the tightness of the section of their fit to the column decreases, while in the basement section it remains unchanged. To reduce the degree of sealing of the pipe dies with a column to the norm, all the dies, including the pipe ones, approach the column by the amount of wear of the pipe dies, and the socle ones - to the base. In this case, the rounded labyrinth coils 12.3 of the socle are pressed into the rubber lining without destroying its surface and residual stresses in it. The described method of increasing the durability of pipe rams is applicable until the labyrinth coils 12.3 are fully inserted into the body of the lining 7.3 (without exceeding the permissible specific pressure) and the corresponding amount of deformation of the side mutually adjacent parts of the linings, with appropriate thickness and elasticity. After the lining of the tube plates is worn to the standard value, they are replaced by others, and the lining of the socle remains without replacement for the term of the raining, for example, 5-10 times of lining of the tube dies,

The preventer is completely devoid of components and parts that cause doubts in their performance. Eliminates the possibility of slagging the crankcase of a chuck containing worm gears and gear bevel gears that ensure the movement of dies, expands the range of use of the preventer in downhole media of any degree of sloughing.

The use of stacked dies, which are blockable for operation, and separately replaced as they deteriorate, and the presence of special labyrinth elements on the die crankcase base, contribute to an increase in the durability of their lining, not less than 2-3 times gross and significantly reduces the labor costs of ensuring their performance.

A significant rise of the dies relative to the rack, their carrier, significantly reduces the phenomenon, which tends to create a misalignment of this rail. Failure to use the case in which the famous cartridge was placed

0 and its connection with the ram case under the new scheme - facing, significantly improves the operating conditions of the cartridge, increasing its durability. In addition, ceteris paribus, the weight of the proposed crankcase

5 is less than the weight of the body of the famous preventer by about 2.5 times, and the outer diameter - by 160-200 mm. Particularly noteworthy is that with the most widely used bore diameter preventer / 1, equal to 215-230 mm, its height (N) does not exceed 250 mm. An extremely important factor in the modern economy (when the country's machine-building industry is able to produce only a certain fraction of the required output) is that the manufacture of a preventer with such a high technical characteristic reduces to the cheapest - turning method of making a die crankcase 12.0 and change the cam part of the toothed racks of the standard lathe chuck to the die. As a result of the simplest and at the same time most reliable preventive design based on the technology

In accordance with the traditional, for example, ram preventers, the feasible lower-class machine-building enterprises, the cost of its manufacture will be reduced by no less than 5 to 10 times. AT

0 highly maintainable. From a single preventer, but completed with different dies, for example, deaf and pipe pipes of two different diameters, it is possible to build a three-way lock.

5 wells of three preventers, the total height (N) of which will be 750 mm. Of the known general purpose spot preventers, the proposed has the highest technical performance.

Claims (1)

0 claims A preventer comprising a housing in which staged sealing dies are placed and a drive mechanism thereof in the form of a self-centering turning patron, characterized in that, in order to increase the reliability of the preventer during the pivot of the drill string, each step step plate is made with a vertical groove on the end and a clip U-shaped cross section, which has on its outer surface a sealing element and a vertical protrusion for placing a stepped die in the groove, and the casing is made with triangular annular projections cross-section with rounded top element of the holder, us and an annular groove under them, and the step die has the answer to placing them in the groove of the core, the thickness of the seal is 1.5-2.0 times greater than body element cage the chat plate has reciprocal protrusions for placing them in the groove of the housing, while the thickness of the sealing element of the die is 1.5-2.0 times greater than the thickness of the seal ,eleven eleven  / 7.7 77 14 82 1 1 Fig.Z tfte4 8.0v- & 8.18.1 77 7 # J ys I FIG. 6 Phie.1