RU175351U1 - PRE-VENT DIES CASE - Google Patents

Abstract

The technical solution relates to the oil and gas industry, to the working bodies of the die preventer, and in particular to the design of the die body. The casing of the preventer die is made of solid metal, contains the upper 1, lower 2, front 3, rear 4 and two side 5, 6 surfaces (faces), from the front surface, a seat 7 is made under the first seal, from the upper surface side a seat 8 is made under the second seal, from the back surface, a connecting element 9 is made, the housing is made of alloy structural steel containing chromium, nickel, copper, the roughness (Ra) of the upper and lower surfaces is not more than 2.5 μm. Hardness of surfaces is not less than 230НВ. The upper and lower surfaces have a hardened outer layer S. The hardened outer layer S is formed by oil chemical oxidation. The technical result consists in increasing the stability of the die body to external destructive influences. 9 s.p. f-ly, 12 ill.

Description

Technical field

The technical solution relates to the oil and gas industry, to the working bodies of the die preventer, and in particular to the design of the die body. The block preventer is designed to seal the mouth of oil and gas wells by blocking, by means of a ram shutter, the annular gap between the casing lowered into the well and drill pipes (tubing, tubing) or closing the well head. A ram valve consists of two dies, opposite mounted in the preventer housing and blocking the through axial channel (central passage bore) with or without a pipe. The designs of the dies differ depending on whether the pipe (tubing) is located in the through-passage channel and whether the blind pipe shear dies are.

The operation of preventers is carried out under the conditions of aggressive environmental influences. Working medium (fluid) - oil, gas, gas condensate, produced water, flushing fluid and their mixtures with a total content of CO ₂ and H ₂ S up to 15% by volume of each and content of mechanical impurities up to 25 mg / l. In winter, preventers are operated at low temperatures (up to - 45 ° C). These factors adversely affect the service life of the piston locks, reduce its performance, durability, reliability, reduce the repair interval and MTBF, reliability. In this case, uptime under such conditions should be about 500 cycles of closing and opening the ram shutter. Failures in the operation of the ram preventer shutters cause a depressurization of the wellhead, the through axial channel does not overlap, which leads to accidents, fluid is released.

State of the art

There are various designs of casing dies preventer. In particular, a preventer die (SU 1273504; [1]) is known, comprising a composite housing and a seal located therein with support elements made in the form of inserts and end stops. The die body [1] is made in the form of a half-ring, has an upper and lower surface, a front surface, a cylindrical surface (rear-side surface).

A known preventer die (RU 2274729; [2]). The preventer die [2] comprises a housing, a liner located on the inside of the housing, and a seal. The die body [2] is made in the form of a half ring, has an upper and lower surface, a front surface, side surfaces, a rear cylindrical surface on the side of which a T-shaped groove is made.

The case of these analogues [1; 2] does not have any protective or antifriction coatings on surfaces in contact with an aggressive working environment. The housing of the dies requires the installation of a seal of complex geometric shape. The die has a bulky composite structure. The die channel of the preventer for such dies should have a larger cross section, which accordingly increases the dimensions of the preventer. The surface of the casing in contact with the guides of the casing is subject to wear and tear, as it is not adapted for mechanical contact under aggressive environmental conditions. Roughness of surfaces (cleanliness) does not ensure durability.

A known set of dies tube preventers (RU 94277; [3]). A known set of dies deaf preventers (RU 94278; [4]). The set of dies [3; 4] for the preventer contains two dies with a front seal at the junction of the dies and an upper seal for the upper mirror of the die channel in each die. The body of each die is made of an integral (integral, monolithic) structure and has the shape of a parallelepiped with a beveled rear face (surface), in which a blind T-groove is made, open from the bottom face of the die to connect the die to the preventer drive rod. A groove is made on the upper face of the body, having the shape of a semicircle with a center displaced from the front to the rear faces, and directly extending to the front face, the area in which the upper seal is located. In the front face of the housing, a groove is made blind with a lower, upper and side faces, connecting with a groove on the upper face and serving to accommodate the front seal, having the shape of a rectangular parallelepiped. The housing has a threaded hole for transportation. In the front face of the die body [3], a through semicircular selection was made with a diameter d for the pipe, the value of which is larger than the diameter of the pipe being sealed, while its center coincides with the axis of the through central channel under the pipe (theoretical axis of the through vertical channel of the preventer). On the lower edge of the die body [3], a groove is made for installation by means of two tooth guzhons, which serves to pre-center the pipe, and a groove for the tooth to enter from the paired die.

In most cases, corrosion-mechanical and fatigue damage arise on the surface of the material, protection of the surface layer of the body is of fundamental importance in its durability. The case of these analogues [3; 4] does not provide easy sliding of the die along the guides of the die channel of the housing and resistance to aggressive effects of the working environment, low temperatures. Cases of dies [3; 4] do not possess anticorrosive and / or antifriction properties, are not equipped with protective coatings or specially treated surfaces, and optimum surface roughness is not ensured (surface cleanliness). When the housing contacts a working medium with a CO ₂ and H ₂ S content of up to 15% by volume and a solids content of up to 25 mg / l at low temperatures up to minus 45 ° C, these drawbacks adversely affect the service life of ram valves and their durability and uptime. The operating time of 500 cycles of closing and opening the ram shutter is not ensured. Repair or replacement of a preventer is required.

The known preventer die hydraulic double PPG2-STTs (RU 131797; [5]) containing a housing with an axial channel in which working bodies are installed - pipe dies and dice dies equipped with drive mechanisms. The die (pipe, deaf) consists of a body, a sealant (pipe, deaf), a top seal, pins that connect the die body and seals. Seals made of elastomer are installed in the corresponding grooves of the housing. The tube die body contains a T-slot for connection with a hydraulic actuator. The body of the die is made in the form of a parallelepiped, has an upper, lower, front, rear and two side surfaces (faces). The die body is made with a horizontal T-shaped groove on the back surface side for connection through a T-shaped hydraulic shank. The ribs between the rear surface and the side surfaces are beveled, i.e. the back surface goes to the side through an inclined surface in the form of a chamfer.

The die body [5] does not provide resistance to aggressive effects of the working environment, low temperatures, mechanical loads, does not have anticorrosion and / or antifriction properties, is not equipped with protective coatings or specially treated surfaces, and optimum surface roughness is not ensured (surface cleanliness). When the housing contacts a working medium with a CO ₂ and H ₂ S content of up to 15% by volume and a solids content of up to 25 mg / l at low temperatures, up to minus 45 ° C, contact surfaces wear, destructive changes in the housing material, material production cases, scuffs and scratches of the mirror guides of the case. These shortcomings adversely affect the service life of the dies, the reliability of the die shutter and reduce the length of the overhaul period of the preventer. The operating time of 500 cycles of closing and opening the ram shutter is not ensured.

Known dies (the website of LLC Trading House NeftePromTechService LLC, an electronic catalog of products on the Internet, the main page is the section on blowout products - die preventers - dies, access mode: http://tdnpts.ru/proborud2.htm [6] ) The die (pipe, deaf) consists of a housing, a sealant (pipe, deaf), and a top seal. The body of the die is made in the form of a parallelepiped, has an upper, lower, front, rear and two side surfaces (faces). Seals are installed in grooves in the upper and front surfaces of the housing. The lateral surfaces are beveled to the rear surface, i.e. the back surface goes to the side through an inclined surface in the form of a chamfer. The die body is made of high strength alloyed heat-hardened steel.

The die body [6] provides for heat treatment, which complicates the production technology and increases the cost of manufacturing the die body; optimal surface roughness (surface cleanliness) is not provided. The analogue does not contain a connecting element, for example, in the form of a T-groove on the back surface side for connection with a pusher of the drive mechanism. In the process of thermal hardening of alloy steel, various defects appear - temper brittleness, dendritic segregation (heterogeneity), flocs (kink, crack), this causes a decrease in mechanical properties. Even with the strictest observance of correctly established technological regimes, these defects cannot be completely eliminated. As a result, the housing does not provide sufficient corrosion resistance in an aggressive working environment. From frequent openings and closures of the preventer, the upper surface of the die body wears out. The axial force acting on the die can also cause destruction of the die body, since the pressure in the preventer at which the seal is firmly pressed against the pipe and ensures complete closure of the pathways of the working medium reaches 70 MPa. Heat treatment of alloy steel reduces toughness, leads to brittleness of the material and increases the likelihood of chips and cracks when mechanical particles enter the friction surface. During the operation of the preventer, friction surfaces wear out when the mating parts are in contact, namely the upper and lower surfaces of the die body and the guides (mirrors) of the preventer body, while the gap between them increases and the die needs replacement, and the overhaul of the preventer body is required. Destruction processes, such as friction, wear, setting, arise and develop under the influence of mechanical and electrochemical effects of the medium on the material of rubbing pairs. The physical and mechanical parameters of the surface, as well as the structure of the surface layer and lubrication conditions, have a significant impact on the wear resistance of parts, the reliability and durability of tribological conjugations.

Disclosure of the essence of the technical solution

The technical problem to which the utility model is aimed is to increase the durability and reliability of the die preventer, to improve the performance of the die preventer, such as reliability, overhaul interval, by increasing the resistance of the die body to external destructive effects - chemical exposure to the working environment, mechanical the effects of the housing guides, the loads from the contact of the die with the die and / or the die with the pipe (tubing).

The technical result consists in increasing the stability of the die body to external destructive influences, increasing the life of the die.

The technical result is ensured by the fact that the casing of the preventer die is made of solid metal in the shape of a parallelepiped, contains upper, lower, front, rear and two side surfaces (faces), a seat under the seal is made on the side of the front surface, a seat under gasket, a connecting element is made from the back surface, the housing is made of alloy steel, the arithmetic mean of the absolute values of the deviation of the profile within the bases howl length (surface roughness Ra) of the upper and lower surfaces is not more than 2.5 micrometers.

The specified entity ensures the achievement of the claimed technical result.

Preferably, the preventer die body is made of alloy structural steel containing chromium, nickel, copper.

Preferably, the surface hardness is in the range of 230 ... 290 HB (units according to the Brinell method).

Preferably, the upper and lower surfaces comprise a hardened outer layer.

It is envisaged that in the casing of the preventer die, the surfaces are chemically oxidized by oiling, or have a zinc plating, or have a chromium plating, or have surface hardening formed by blasting with balls.

It is also envisaged that the ribs between the surfaces are chamfered. This provides the convenience of installing the dies in the half-cavity.

Preferably, the die body is made integral by the technology of layer-by-layer build-up of metal layers (English selective laser sintering, SLS, Selective laser melting, SLM) from an alloy of a metal powder.

In contrast to the known die bodies, the proposed technical solution reduces the expected wear of the die body and the guides of the gearbox during operation, which allows to increase the life of the die by almost half.

The essence of the utility model is illustrated, but not limited to the following description of the tube die body and graphic materials that depict:

FIG. 1 - casing of a tube die of a preventer, general view from the front surface side;

FIG. 2 - casing of a tube die of a preventer, general view from the rear surface side;

части, общий вид;FIG. 3 - casing of the tube die preventer with a cutout

parts, general view;

FIG. 4 - casing of the tube die of the preventer, top view;

FIG. 5 - casing of the tube die of the preventer, bottom view;

FIG. 6 is a body of a tube die of a preventer, a side view in section.

FIG. 7 - casing of a blank die of a preventer, general view from the front surface side;

FIG. 8 - casing of a blank preventer die, general view from the rear surface side;

части общий вид;FIG. 9 - the case of a blank die preventer, with a cut

parts general view;

FIG. 10 - casing of a blank die preventer, top view;

FIG. 11 - casing of a blank die preventer, bottom view;

FIG. 12 is a casing of a blank die of a preventer, a side view in section.

Tube body

The casing of the preventer tube die is made of solid metal in the shape of a parallelepiped by preliminary machining of the steel billet (rolled, forged, casted) with macrogeometry of its surface. The tube die body is made of alloy structural steel - Steel 40X GOST 4543-71. Moreover, Steel 40X can be replaced by Steel 45X, Steel 38XA, Steel 40XH, Steel 40XC, Steel 40XF, Steel 40XP according to GOST 4543-71, Steel 40X13, Steel 30X13 according to GOST 5632-72. The housing contains the upper 1 (Fig. 1; 2; 3; 4; 5; 6), the lower 2 (Fig. 1; 5; 6), the front 3 (Fig. 1; 3; 4; 5; 6), the rear 4 (Fig. 2; 3; 4; 5; 6) and two side 5 and 6 (Fig. 1; 2; 3; 4; 5) surfaces. On the side of the front surface 3, a seat 7 (Fig. 1; 3; 6) is made under the end (pipe) seal. From the side of the upper surface 1, a seat 8 (Fig. 1; 2; 3; 4; 6) is made, under the upper seal. Sealers are replaceable elastic rubber inserts, rubber of the IRP-1396 and IRP-8470 brands, or rubber-metal with embedded metal elements. Elastic gaskets allow you to block micro- and macro-irregularities on the surfaces of the pipes. From the side of the rear surface 4, a connecting element 9 is made (Fig. 1; 2; 3; 4; 5; 6), designed to connect the die with the pusher of the drive mechanism of the preventer plate. The connecting element 9 is made in the form of a through T-groove. The T-shaped groove can be made both through and deaf. In FIG. 1 to 6 shows the connecting element 9, made in the form of a through T-groove passing from the upper surface 1 to the lower 2. In this case, the T-groove can be made in the transverse direction, that is, directed from one side surface 5 to the opposite side surface 6. The connecting element 9 may be made in the form of a movable connection of another design, providing the transfer of force from the pusher to the die body. The housing is made with a beveled rear surface 4 (surface). The bevel 10 (Fig. 4; 5) is made from the side surfaces 5 and 6 to the rear surface 4. The bevel 10 is made at an angle "a" equal to 30 degrees (Fig. 4; 5) symmetrically for each side surface 5, 6 The seat 8 (Fig. 1; 2; 3; 4; 6), under the seal, on the upper surface 1 of the body is made in the form of a radius groove (ring groove) 11 (Fig. 4; 6), has the shape of a semicircle with straight slots 12 (Fig. 4), facing the front surface 3. The faces of the radius groove 11 are located at an angle e = 24 ° (Fig. 6). Slots 12 connect the seat 8 under the upper seal with the seat 7 under the end seal. In the slots have an upper seal. The seat 7 under the end seal in the front surface 3 of the housing is made in the form of a groove 13 (Fig. 6) deaf from the bottom 2, top 1 and side 5, 6 surfaces. The groove 13 is connected to the groove 11 through the slots 12 and is made with a radius recess 14 (Fig. 3). On the front surface 3 of the casing, a through semicircular selection was made with a diameter d (Fig. 4; 5) for the pipe, the diameter d being greater than the diameter of the pipe being sealed, while its center coincides with the axis of the through central channel under the pipe (theoretical axis of the vertical through channel of the preventer). For example, for a pipe with a diameter of 73 mm, the diameter d is 74 mm. On the side of the front surface 3 from the bottom, the housing is equipped with a tooth 15 (Fig. 1; 3; 4; 5) for centering the pipe. Symmetrically to the tooth 15, on the opposite side of the casing, on the side of the front surface 3, a recess 16 (Fig. 1; 3; 5; 6) is made for the tooth 15 of the opposing die when the ram shutter is connected. Tooth 15 is made integral with the rest of the body. At the same time, the implementation of the tooth 15 whole (integral) with the body is not required. Tooth 15 can be made as a separate part and installed in the body of the die by means of gujons, countersunk screws. The die body has a threaded hole (not shown) for transportation and a hole 17 (Fig. 3; 4; 5) for embedded elements of the seals. The ribs between the upper 1, lower 2, front 3, rear 4 and side 6 surfaces are made with chamfers (not marked). The hardness of the upper 1 and lower 2 surfaces, measured by the Brinell method, is in the range 270 ... 290NV. The hardness of the remaining surfaces 3, 4, 5, 6 within less than 230 ... 270NV. The purity of at least the upper 1 and lower 2 surfaces (the arithmetic mean of the absolute values of the deviation of the profile within the base length is the roughness Ra) is not more than 2.5 micrometers. The required roughness is achieved by forming a hardened outer layer S (FIG. 6). Its goal is to increase surface hardness with high core viscosity, smooth microrelief, reduce microcracks, reduce friction forces, increase wear resistance, increase fatigue resistance and improve corrosion resistance. The hardened outer layer S is formed at least on the upper 1 and lower 2 surfaces, as well as on other mating surfaces. A hardened outer layer S, satisfying the operating conditions of the housing in an aggressive working environment with a CO ₂ and H ₂ S content of up to 15% by volume and mechanical impurities up to 25 mg / l, at low temperatures up to minus 45 ° C, is obtained depending on technological capabilities of production and the final cost of production by machining surfaces (flat grinding, fine milling, flat smoothing, polishing) or chemical oxidation by oiling, or by zinc galvanic rytiya or chrome plating or zinc-plating hromatirovnnogo or peening jet of balls (glass beads). In addition, the hardened outer layer S can be formed by technologies of carburization, nitriding, cyanidation and nitrocarburizing.

Chemical oxidation by oiling is an intentional process of oxidizing the surface layer of metal products in heated sodium hydroxide solutions with the addition of sodium nitrate or nitrate. Provides long-term operation without corrosion, while during processing there are no significant changes in the dimensions of the part, the maximum deviation is up to 1.2 microns.

Surface hardening of the upper and lower surfaces, formed by blasting with balls (glass bead), provides protection against corrosion-mechanical and fatigue damage, provides a surface roughness of Ra 0.32 μm. It is known that the development or appearance of cracks occurs in the material zone with tensile stresses (mechanical) where there are compressive stresses, the development of cracks does not occur.In the process of blasting with balls, each ball acts on the material and forms on its surface and small overlapping recesses (imprints), deforms the material and thereby strengthens the surface. Under such a surface, the material tends to return to its original state, as a result of which a layer with compressive stresses forms under the deformed material. A uniform hardened layer with high compression stresses forms on the surface of the material, which significantly increases the strength, reliability, durability of the casing of the preventer die. Also, surface hardening of the upper and lower surfaces can be formed by flattening, in particular, with a diamond indenter. Diamond smoothing is the process of plastic deformation of an initial microprofile under the action of a force applied to a diamond (or other superhard material) indenter. Plastic deformation of the metal leads to smoothing of the microcrests of the treated surface and the filling of the microprofile cavities with the volume of the deformed scallops. By smoothing, a surface roughness of Ra from 0.08 to 0.32 μm is obtained, and a riveted hardened layer is formed, the propagation depth of which reaches several tenths of a millimeter, and the degree of hardening is from 40 to 200%. In the hardened layer S, compressive residual stresses of up to 700 MPa are induced. These characteristics of the surface layer can significantly increase the wear resistance, contact fatigue strength, and corrosion resistance of the die body.

Blind body

The body of the blank die of the preventer is made of solid metal in the form of a parallelepiped by preliminary machining of the steel billet (rolled, forged, casted) with macrogeometry of its surface. The case is made of alloy structural steel - Steel 40X GOST 4543-71. Moreover, Steel 40X can be replaced by Steel 45X, Steel 38XA, Steel 40XH, Steel 40XC, Steel 40XF, Steel 40XP according to GOST 4543-71, Steel 40X13, Steel 30X13 according to GOST 5632-72. The case of a blank plate contains the upper 1 (Fig. 7; 8; 9; 10; 11; 12), the lower 2 (Fig. 7; 8; 9), the front 3 (Fig. 7; 2; 10; 11; 12), back 4 (Fig. 8; 9; 10; 11; 12) and two lateral 5 and 6 (Fig. 7; 8; 9; 10; 11) surfaces. From the side of the front surface 3, a seat 7 (Fig. 7; 9; 12) is made under the end (deaf) seal. From the side of the upper surface 1, a seat 8 (Fig. 7; 8; 9; 10; 12) is made under the upper seal. Seals are replaceable elastic liners, rubber or rubber-metal with embedded metal elements. From the side of the rear surface 4, a connecting element 9 is made (Fig. 7; 8; 9; 10; 11; 12), designed to connect the die to the pusher of the drive mechanism of the preventer plate. The connecting element 9 is made in the form of a through T-groove. The T-shaped groove can be made both through and deaf. The T-shaped groove extends from the upper surface 1 to the lower 2. In this case, the T-shaped groove can be made in the transverse direction, that is, directed from one side surface 5 to the opposite side surface 6. The connecting element 9 can be made in the form of a movable connection another design that provides the transfer of force from the pusher to the die body. The body of the deaf die is made with a beveled rear surface 4 (surface). The bevel 10 (Fig. 10; 11) is made from the side surfaces 5 and 6 to the rear surface 4. The bevel 10 is made at an angle “a” equal to 30 degrees (FIG. 10; 11) symmetrically for each side surface 5, 6 The seat 8 (Fig. 7; 8; 9; 10; 12) under the seal on the upper surface 1 of the housing is made in the form of a radius groove (ring groove) 11 (Fig. 10; 12), has the shape of a semicircle with straight slots 12 ( Fig. 10), facing the front surface 3. The faces of the radius groove 11 are located at an angle e = 24 ° (Fig. 12). Slots 12 connect the seat 8 under the upper seal with the seat 7 under the end seal. In the slots have an upper seal. The seat 7 under the end seal on the front surface 3 of the housing is made in the form of a groove 13 (Fig. 12), deaf from the bottom 2, top 1 and side 5, 6 surfaces. The groove 13 is connected to the groove 11 through the slots 12. The body of the blind plate has two threaded holes (not shown) made on the side faces for transportation and holes 17 (Fig. 9; 10; 11) for embedded elements of the seals. The ribs between the upper 1, lower 2, front 3, rear 4 and side 6 surfaces are made with chamfers (not marked). The hardness of the upper 1 and lower 2 surfaces, measured by the Brinell method, is in the range of 230 ... 260NV (units by the Brinell method). The hardness of the remaining surfaces 3, 4, 5, 6 is not less than 230NV. The roughness (according to Ra) of the upper and lower surfaces is not more than 2.5 micrometers. The required roughness is achieved by forming a hardened outer layer S (FIG. 12). The purpose of layer S formation is to increase surface hardness with high core viscosity, smooth microrelief, reduce microcracks, reduce friction forces, increase wear resistance, increase fatigue resistance and improve corrosion resistance. The hardened outer layer S is formed at least on the upper 1 and lower 2 surfaces, as well as on other mating surfaces. A hardened outer layer S, satisfying the operating conditions of the housing in an aggressive working environment, with a content of CO ₂ and H ₂ S up to 15% by volume and a content of mechanical impurities up to 25 mg / l at low temperatures up to minus 45 ° C, is obtained by machining (finishing milling). The hardened outer layer S is formed by machining surfaces (flat grinding, fine milling, flat ironing, polishing), or by chemical oxidation by oiling, or zinc plating, or chrome plating, or zinc-chromium plating, or surface hardening by spherical beads or cementation, or nitriding, cyanidation and nitrocarburizing. Provide a roughness of surfaces 1 and 2 at Ra 0.32 μm.

A variation of a blind die is a shear (shearing, cutting) die (not shown), which can cut a pipe (tubing) and block an open well. The shear die body is made of solid metal in the shape of a parallelepiped by preliminary machining of the steel billet (rolled, forged, casted) with macrogeometry of its surface. The case is made of alloy structural steel - Steel 40X GOST 4543-71. Moreover, Steel 40X can be replaced by Steel 45X, Steel 38XA, Steel 40XH, Steel 40XC, Steel 40XF, Steel 40XP according to GOST 4543-71, Steel 40X13, Steel 30X13 according to GOST 5632-72. The shear die housing comprises an upper, lower, front, rear, and two side surfaces. On the front surface side, a cutting edge is made (cutting edge, knife, cutter). For cutting pipes without crushing them during the cutting process, the cutting face in the plan is preferably made at an angle (cuts the pipe at an angle), for example in the form of a wedge. On the front surface side, a seat is made under the end seal. On the upper surface side, a seat is made under the upper seal. On the back surface side, a connecting element is provided for connecting the die to the pusher of the drive mechanism of the preventer plate. The connecting element is made in the form of a T-groove. The hardness of the upper and lower surfaces, measured by the Brinell method, is in the range of 240 ... 290 HB (units according to the Brinell method). The roughness (according to Ra) of the upper and lower surfaces is not more than 2.5 micrometers. The required roughness is achieved by machining the surfaces (flat grinding, fine and fine milling) or by forming a hardened outer layer S on the mating surfaces. The hardened outer layer S is formed by oily chemical oxidation, or zinc plating, or chromium plating, or zinc-chromium plating, or surface hardening with spherical beads, or carburizing, or nitriding, or cyaniding and nitrocarburizing, or diamond smoothing.

The casing of the preventer die is used as follows.

Use of tube die body. The upper and end seals are installed in the tube body of the preventer tube. Dies are installed in the preventer. The preventer housing contains cavities designed to accommodate pipe dies. The cavities are located across the longitudinal axis of the central passage hole. The die cavities are provided with guide thrust protrusions with mirror surfaces. Dies are installed in the die cavity of the preventer. In the upper cavities, two tube dies are installed opposite, together forming a ram valve. The dies in the cavities are installed with the possibility of reciprocating motion in the direction of the central passage channel. Each die is connected to its own drive mechanism by installing a T-shaped shank of the pusher in the T-shaped groove of the die. The preventer is installed at the wellhead. To seal the wellhead, the central bore hole is closed. If there are pipes in the well, pipe dies are closed using drive mechanisms. The drive mechanisms move the plates towards the central passage channel. The dies move in the preventer housing independently of one another. As a result of oncoming movement, the dies reach the surface of the pipes to be sealed and tightly compress them. The end and top seals are elastic deformed and fill the gaps between the mating surfaces. The tooth 15 of each die enters the recess 16 of the opposite die.

Use of a blank die body. The case of a deaf die is used similarly. A blank die is assembled, for this, the upper and end seals are installed in the body of the blind die. Opposite install two deaf dies in the lower dice cavity, together forming a die valve, and connect with the mechanisms of drive dies. Blind dies are used to close a well in which there is no drill string or casing. In the absence of pipes in the well, blank dies are closed. Using the drive mechanism of the dies, close or open the ram shutter. The process of closing blind dies is similar to the process of closing tube dies. In this case, the dies move towards the central passage channel and in their extreme closed position contact the front surfaces and block the well. Shear dies are used to shut off a well in which there are pipes. In this case, the cutting face on the front surface cuts the pipe and the two shear dies are closed, sealing the well. Since the body is made of all-metal alloyed stainless steel, with a surface roughness of not more than Ra 2.5 micrometers, and in addition, the surface hardness is at least 230 HB (Brinell units), the surfaces are equipped with a reinforcing outer layer S, it provides easy glide of the die along the guides of the die channel of the preventer housing and resistance to aggressive effects of the working environment, low temperatures. The die body has anti-corrosion (no microcracks, an aggressive working environment does not fall into the metal structure) and anti-friction properties (surface microrelief). When the housing contacts a working medium with a CO ₂ and H ₂ S content of up to 15% by volume and a mechanical impurity content of up to 25 mg / l at low temperatures up to minus 45 ° C, over 500 closing cycles are ensured by mechanical interaction with the preventer housing - opening the slide shutter. Surfaces 1, 2, 5, 6 of the die body in contact with the guides of the preventer housing are less susceptible to wear and tear, as they are more suitable for mechanical contact under conditions of aggressive exposure to the working environment in comparison with known analogues.

Thus, through the use of a utility model, the preventer die housing, which is resistant to the external destructive effect of the working medium, and the mechanical loads from the preventer housing rails, increase the durability and reliability of the die preventer, improve the performance of the die preventer, such as reliability, overhaul interval.

The technical solution can be implemented in modern industrial enterprises, from known materials, by known means. The utility model is applicable for the specified purpose and provides the claimed technical result.

Claims (10)

1. The casing of the preventer die, characterized in that it is made of solid metal in the form of a parallelepiped, contains upper, lower, front, rear and two side surfaces, a seat for the seal is made on the side of the front surface, a seat for the seal is made on the side of the upper surface, a connecting element is made on the back surface side, the housing is made of alloy steel, the arithmetic mean of the absolute values of the deviation of the profile within the base length of the upper and lower its surfaces is not more than 2.5 microns. 2. The body of the preventer die according to claim 1, characterized in that it is made of alloy structural steel containing chromium, nickel, copper. 3. The body of the preventer die according to claim 1, characterized in that the surface hardness is at least 230 HB. 4. The body of the preventer die according to claim 1, characterized in that at least the upper and lower surfaces have a hardened outer layer. 5. The body of the preventer die according to claim 4, characterized in that at least the upper and lower surfaces are chemically oxidized by oiling. 6. The casing of the preventer die according to claim 4, characterized in that at least the upper and lower surfaces are zinc plated. 7. The casing of the preventer die according to claim 4, characterized in that at least the upper and lower surfaces are chrome plated. 8. The casing of the preventer die according to claim 4, characterized in that at least the upper and lower surfaces have surface hardening formed by blasting with balls. 9. The casing of the preventer die according to claim 1, characterized in that the ribs between the surfaces are chamfered. 10. The casing of the preventer die according to claim 1, characterized in that it is made integral by the technology of layer-by-layer buildup of metal layers from an alloy of metal powder.

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