WO2023096528A1

WO2023096528A1 - Pipeline swivel joint

Info

Publication number: WO2023096528A1
Application number: PCT/RU2022/000329
Authority: WO
Inventors: Валерий Викторович ВАКУЛОВ
Original assignee: Валерий Викторович ВАКУЛОВ
Priority date: 2021-11-23
Filing date: 2022-11-08
Publication date: 2023-06-01

Abstract

The invention relates to the pipeline transport of oil, petroleum products, liquid chemical products, liquefied natural gas (LNG), gas condensate and other liquid, gaseous and flowable products. It can be used in loading arms, filling, loading and transfer hoses, articulated pipelines and manipulators, marine loading arms for use in oil, chemical and gas terminals at sea and river ports and between floating vessels at sea, and is also applicable in loading and unloading facilities for rail and road tankers, top loading hose assemblies, bunkering facilities for sea and river vessels, facilities for fueling space rockets, and fire hoses, as well as in facilities for unloading flowable food products and in connectors. A pipeline swivel joint comprises a swivel assembly having two structural flanges and two housings, each of which has at least two parallel bearing races. One of the housings acts as a stator and the other as a rotor, and the bearing races are in the form of arcuate V-grooves. Provided in the housing of the stator and of the rotor is a channel for supplying an inert gas to a cavity of the swivel assembly, and seals on the transported product side are arranged inside the swivel assembly behind a retaining shoulder, and the swivel assembly is provided with a leak inspection port that allows for installation of a leak detection sensor. The technical result is the creation of a swivel joint with a high load-bearing capacity, which is capable, inter alia, of withstanding high axial and radial loads, as well as providing leak-tightness.

Description

HINGE FOR PIPELINES

Technical field

This technical solution relates to the field of pipeline transportation of oil, petroleum products, liquid chemical products, liquefied natural gas (LNG), gas condensate and other liquid, gaseous (including boil-off gas) and fluid products (hereinafter referred to as the transported product) as part of standers, loading, loading, reloading hoses, articulated pipelines and manipulators, loading arms for use at oil, chemical, gas terminals of sea and river ports, at sea between boats, and is also used in installations for draining and loading railway tanks and tank cars, hose installations loading, bunkering installations for refueling sea and river vessels, in space rocket refueling installations, fire hoses, as well as in installations for the shipment of food fluid products and connectors.

State of the art

It is known from the prior art that a hinge is a sealed hollow assembly that provides a movable connection of two pipes of a product pipeline (pipeline) with rotation around its axis (standard, STO Gazprom 2-3.4-1255-2021 "Infrastructure for the production, storage and shipment of liquefied natural gas . Stender Equipment. General Specifications.").

It is also known that in accordance with OSIMF "International Maritime Forum of Oil Companies""Design and construction specification MARINE STENDERS", ISO 16904:2016 "Oil and gas industry - Design and testing of offshore LNG transfer arms for conventional onshore terminals", STO Gazprom 2 -3.4-1255-2021 "Infrastructure for the production, storage and shipment of liquefied natural gas. Stender equipment. General specifications" hinge (swivel joint) is considered as a separate nodal element construction of equipment (stand arms, transfer arms, hose installations), for which there are special requirements for operation, performance of a set of calculations, as well as requirements for testing and criteria for assessing the passing of tests.

A stander is known (patent SU619385A1 dated 10/13/1975, class IPC B63B 27/24), containing a riser, an arrow connected to the riser by a hinge and consisting of two converging pipes and an upper tubular belt, jointly forming a pyramidal truss, while the pipes and belt are connected spacers. In addition, the stander contains a jib, a connecting device with a branch pipe, a shank with counterweights and a cable-block drive. The advantages of the proposed design of the stander is an improved design, consisting of two converging pipes and an upper tubular belt, which together form a pyramidal truss, i.e. in fact, a two-arm design of the stander boom is proposed. Accordingly, the load is distributed evenly on two arms and two hinges mounted on the shoulders in parallel, and not on one boom arm and one hinge, as was the case in other designs, and thus is evenly distributed over the hinges. Thus, the axial and radial load is applied to each shoulder hinge by half.

The disadvantage of this stander is the installation of at least two additional hinges on the second pipe (shoulder) of the boom, the additional weight of the second pipe and counterweight, the assembly of the hinged transition from the support to the two boom pipes, which is difficult to manufacture, which increases the total weight of the equipment, its cost and labor intensity in production. . In addition, the characteristics, technology and design of the hinges in this invention of the stander are not considered.

A hinged device is known, considered in the drive for turning articulated pipelines (patent RU160741U1 dated 09/17/2015, class IPC F16L 27/02), containing a pair of movably articulated pipes and an engine, while a worm gear is added to the drive, and the worm connected to the engine , is fixed on one pipe, and the worm wheel is fixed on the other pipe of the pair. In addition, a sensor has been added to the drive for turning articulated pipelines to control the mutual angular position of the pipes. According to the description and figures presented in the patent, the rotation of articulated pipelines is provided by a single-row bearing placed between two pipeline flanges. A bearing or slewing bearings of this type are a separate key element in the drive for turning articulated pipelines. The disadvantage of this solution is the large dimensions and weight of the swivel device with a bearing, as well as the presence of one row of rolling balls in the bearing, which makes this device applicable in small loading and unloading devices with small axial and radial loads. The hinge device is not applicable in standers and other similar installations, since it does not meet the requirements of current standards, and is also not applicable for LNG shipment, since there is no provision for lubrication of the hinge bearing, which is necessary at cryogenic temperatures.

Known hinges or swivel joints of pipelines, referred to in the composition of "Balanced loading arms" (patent RU2580488 C2 dated May 17, 2011, class MIK B67D 9/02), "Hinged hose for pumping fluid with spring balancing at a large deflection angle (patent RU2240279C2 dated 06/13/2000, IPC class B67D 5/01), “Device for transferring the current environment on the high seas” (patent RU2359859C2 dated 11/22/2005, IPC class B63V27 / 34), “Marine loading system” (US4299261A patent dated 10/17/1979, IPC class B67D9 / 02), Loading arm assembly with a guide cable (patent RU2323867C2 dated 04.20.2004, IPC class B65G67 / 00, B67D5 / 70), “Device with an articulated manipulator for loading and unloading products, in particular fluid products (patent RU2274579C2 dated 09/13/2001, IPC class B63B 27/34, B67D5/70).

The disadvantage of the presented equipment is that the equipment components, including swivel joints, are additionally reinforced by supporting structures. This indicates that the hinges in the above inventions are not designed to hold massive pipelines and booms, which requires the installation of an additional retaining frame, bearings and slewing devices, which leads to a greater increase in the weight of the equipment. At the same time, the lack of opportunities to replace all seals or the hinge itself in the event of depressurization, deformation or wear of the ball raceways in the hinge leads to lengthy, complex and expensive operations for disassembling the entire equipment. In addition, the characteristics, technology and design of the hinges in these inventions are not considered.

Known swivel, mentioned in the design of "Single balanced marine loading arm" (patent US3547153A dated 06/10/1968, IPC class B67D9/02). In the shown in FIG. 5 of the patent in the section of the pipeline, the support assembly with the transition to the boom has three swivel joints, indicated under the numbers: 42 - support hinge; 48 and 52 - arrow pivots. To strengthen the knot and impact radial load, a trunnion with slewing bearings with one raceway is installed on the hinges: 76 and 78. The section of the hinges 42 and 48 shows that the hinges have two housings, each with two ball raceways, one of the housings acts as a stator, the other rotor. The stator is permanently fixed on the pipeline, the rotor is bolted to the flange. A seal 44 is installed between the stator and the flange and a retaining ring 46 is installed. The design of the hinge 52 is distinguished by the absence of a seal 44 and a retaining ring 46 (not shown in Fig. 5 of this patent) due to the absence of a fluid product in this part of the assembly - the hinge performs only a bearing function.

The disadvantage of this solution is that the pipeline transition node with two hinges 42 and 48 from the support to the boom is additionally reinforced with a trunnion frame with a turntable and a bearing hinge 52, this indicates that the hinges are not designed to hold massive pipelines and booms, which requires the installation of an additional retaining frame. The presence of a flange on only one side of the hinge makes it possible to replace the seal 44. On the other side of the hinge, there are no possibilities for replacing the seal - a mud sump, which provides protection against moisture, ice and dirt ingress into the cavity of the ball raceways. In the shown in FIG. 5 of the patent, the sealant - the sump is not specified or absent. The absence of a sealant - a sump is a disadvantage of this hinge design. The wear of the sealant - the sump or its absence leads to rapid wear and deformation of the raceways due to the ingress of dirt, sea water, ice formation in the cavity of the raceways, and this entails the dismantling of all overall and multi-ton equipment. Dismantling the hinge on the pipeline of the equipment is not possible, because the hinge stator is connected to the pipeline by welding. It is possible to separate the rotor from the stator only after removing all the balls. It is very difficult to carry out such work at height. The use of special materials that provide greater bearing capacity and less wear of the rotor and stator of the hinge leads to difficulties in production - welding of different steels of the pipeline stator requires special technological solutions. The retaining ring 46, as a removable element of the hinge, is itself exposed to the product flow and cannot fully close the seal 44 from abrasive and solid impurities in the product flow, as well as from the exit of the seal under the action of vacuum, which can form in the pipeline, which affects the tightness of the hinge .

Known hinge, reflected in the technical solution: "Bearing device with tracks for use in a swivel joint (options) and rotary connection (options) (patent RU2154225C2 dated 06/12/1995, IPC class F16L27 / 00, F16C19 / 02). The bearing device with tracks can be used in a rotary connection of pipes or pipelines. The male connector (acts as a stator) and the female connector (acts as a rotor) of the bearing device have a central axis and a plurality of annular grooves located one above the other in the corresponding plane and forming a ball raceway, each of the grooves has an essentially arcuate cross section, wherein each outer groove in the female connector has a straight segment and an offset radius, and the groove in the male connector is formed with substantially the same radius as a ball bearing. Each subsequent groove and, accordingly, the ball raceway has a radius greater than the radius of the previous groove, so the ball raceways are arranged in steps relative to each previous raceway. The o-ring has an outer sealing surface received by the seal opening so that it seals against the inner peripheral surfaces of the inner portions of the male and female connectors, and has an inner surface substantially flush with the fluid flow path.

This solution allows, due to the stepped arrangement of the tracks, to more evenly distribute the load on the entire set of tracks, and the shape of the grooves of the track allows you to get a large contact area between each ball and the raceway, thereby reducing the load concentration. This solution reduces the likelihood of dents or deformations on the surface of the ball raceways, and the tightness of the improved seal used is less affected by the formation of dents and deformations from the effects of loads. The specified technical solution of the hinge is taken as a prototype.

The disadvantage of the above solution is that the many tracks and their stepped arrangement leads to an increase in the dimensions and weight of the device. The arcuate cross-section of the groove shape ensures that the ball contacts each groove at one point, that is, two points of contact between the ball and the raceway, which take on the load, while the increased contact area leads to excessive friction of the ball on the raceway, which leads to wear with subsequent loss of tightness of the device seal. The flow of a fluid product with possible abrasive content, the speed of which can reach 12 m/s, significantly affects the seal located flush with the fluid flow channel, raising seal, thereby reducing tightness and its service life. Vacuum in the piping can cause leaks in seals that are flush with the fluid flow path.

From the above examples of known inventions, it can be seen that the swivel of the pipeline plays an important role in the design of equipment for loading and unloading and shipment of transported products. The hinge must have a large bearing capacity - this determines the dimensions, weight, labor intensity in production and the cost of equipment, of which the hinge is a part. The hinge must have the ability to replace seals, as well as the ability to replace the hinge itself, including its rotor and stator, without removing the boom and dismantling the equipment for loading and unloading the transported product. The hinge must provide tightness at a given pressure and cryogenic temperatures of the transported product. The hinge should be easy to manufacture and assemble the equipment in which it is located.

The objective of the proposed technical solution is to develop a new swivel cassette-type pipelines for use in the design of standers, loading, loading, reloading sleeves (levers), articulated pipelines and manipulators and other loading and unloading installations for the shipment of oil, oil products, liquid chemical products, liquefied natural gas (LNG), gas condensate and other liquid and gaseous (including boil-off gas) products with a high bearing capacity, including the ability to withstand large axial and radial loads, to ensure tightness at a given pressure and cryogenic temperatures of the transported product. The design of the hinge should provide the possibility of dismantling and replacing seals and the ability to dismantle and replace the rotor and stator of the hinge (cassette principle) without dismantling the equipment of which the hinge is a part, and also reduce labor intensity, metal consumption and cost in the production of the above equipment.

Disclosure of the essence of the technical solution

The technical solution of the above problem is solved due to the fact that the swivel joint of pipelines, containing a hinge having two structural flanges and two housings, each of which is made with at least two parallel ball raceways, while one of the housings acts as a stator, the other as a rotor, where the ball raceway is made in "V"- in the shape of an arch type, while in the stator and rotor housing there is a channel for supplying inert gas to the hinge cavity, and the seals themselves on the side of the transported product are located inside the hinge behind the lug-gate, and the hinge itself has an inspection hole. The specified technical solution provides a large bearing capacity of the hinge, including one capable of withstanding large axial and radial loads, as well as the tightness of the hinge at a given pressure and temperature (including cryogenic) of the transported product, which ensures the use of the hinge in the designs of loaders, loading, loading, reloading arms (arms), articulated pipelines and manipulators and other loading and unloading installations for the shipment of oil, oil products, liquid chemicals, liquefied natural gas (LNG), gas condensate and other liquid, gaseous (including boil-off gas) and fluid products.

A technical solution is possible, where the ball has four points of contact with the “Y”-shaped arch-type raceway, that is, two points of contact per groove of the rotor and stator. The specified technical solution provides a large bearing capacity of the hinge, the ball with a “Y”-shaped arch-type raceway is always in a state of load at all four points of contact, the load and, accordingly, the reaction is evenly distributed over the points of contact of the ball with the track, the total area is larger contact, due to which the hinge has a large bearing capacity, that is, it is able to withstand large axial and radial loads.

A technical solution is possible, where the rotor and stator assembly are bolted between two structural flanges and form a cassette-type hinge. The specified technical solution provides the possibility of dismantling and replacing seals, as well as the ability to dismantle and replace the rotor and stator of the hinge (cassette principle), without disassembling the equipment, of which the hinge is a part, and also reduces labor intensity, metal consumption and cost in the production of the above equipment for product transportation.

A technical solution is possible, where structural flanges can be used with or without a welding collar for pipelines. The specified technical solution provides a reduction in labor intensity, metal consumption and cost in the production of new equipment, of which the hinge is a part, and its subsequent maintenance. The material of the flanges can be similar to the material of the pipeline, which simplifies the welding technology in the production of equipment. The use of structural hinge flanges without a welding collar allows the repair of old standers and other equipment, where there are already two standard flanges, the cassette hinge assembly with structural flanges is installed between two old standard flanges and bolted together, thereby increasing the bearing capacity and extending the service life equipment.

A technical solution is possible, where inert gas is fed into the channel through a fitting located on the stator, then through the channel inside the stator it is supplied to the hinge cavity in three places: the seal area on the side of the transported product, the ball raceway area and the flange seal area and is removed from the hinge cavity through the channel and fitting located on the rotor. The specified technical solution ensures the use of the hinge with explosive transported products, including cryogenic temperatures (CNG), as well as the operation of the hinge at low arctic ambient temperatures.

A technical solution is possible, where the inner cavity of the hinge is divided into at least two zones by sealing rings. The specified technical solution ensures the division of the inner cavity of the hinge according to its purpose, which leads to the correct operation of the seals installed on the side of the transported product, and the absence of lubrication from the area of the ball raceways in this zone and forms a leakage detection inspection zone.

A technical solution is possible, where a leak detection sensor can be installed in the inspection hole. The specified technical solution provides not only visual detection of the initial stage of hinge leakage during the next technical inspection of equipment, which requires hazardous high-altitude work using special equipment and lifting equipment, but also allows real-time information from the leak sensor on the state of the hinge, which increases the safety of equipment operating at hazardous production facilities, which includes hinges.

A technical solution is possible, where the transported product is: oil, oil products, liquid chemical products, liquefied natural gas (LNG), gas condensate and other liquid, gaseous (including boil-off gas) and fluid products. This technical solution provides multifunctional application of the hinge with the above products, depending on its material design.

Brief list of drawings

In FIG. 1 shows a general view of the swivel assembly;

In FIG. 2 shows a section of the swivel joint;

In FIG. 3 shows a section of an LNG swivel joint (for liquid or gaseous products at cryogenic temperatures;

In FIG. 4 shows a schematic section with parallel "V"-shaped arch-type raceways;

In FIG. 5 shows diagrams of reactions from the action of an external radial force or an external axial force on a ball in a “V”-shaped arch-type raceway;

FrO - maximum external radial force acting on the ball;

FaO - maximum external axial force acting on the ball;

RrOl, Rr02; RaOl, Ra02 - reaction from the action of radial or axial force, respectively, on the ball.

Pos. 1 - rotor;

Pos. 2 - stator;

Pos. 3 - rotor flange (structural with a collar for welding to the pipeline);

Pos. 4 - stator flange (structural with a collar for welding to the pipeline);

Pos. 5 - "U"-shaped parallel tracks of arch type with two grooves for rolling balls;

Pos. 6 - primary seal on the side of the transported product;

Pos.7 - secondary seal on the side of the transported product;

Pos. 8 - anti-extrusion ring;

Pos. 9 - sealing ring of the hinge track zone;

Pos. 10 - sealing ring of the stator flange;

Pos. 11 - a sealant that prevents the penetration of external moisture and dirt;

Pos. 12 - plug-fitting with oiler;

Pos. 13 - leak inspection hole and plug screw;

Pos. 14 - inlet fitting for inert gas (nitrogen - N2) on the stator;

Pos. 15 - channel for supplying inert gas (nitrogen - N2) on the stator;

Pos. 16 - channel and fitting for the exit of inert gas (nitrogen - N2) on the rotor; Pos. 17 - additional seal;

Pos. 18 - ledge-shutter on the rotor to hold the seal;

Pos. 20 - ball;

Pos. 21 - touch points of the track ball;

Pos. 22 - hinge cavity;

Pos. 23 - bolts;

Pos. 24 - holes for bolts;

Poz.25 - hinge axis (product transportation channel);

Pos. 26 - through channel for transporting the product, communicating with pipelines;

Implementation of the technical solution

The claimed technical solution uses the following terms and definitions:

The stander (other names found in the literature: sea / river loader, loading, loading arm (lever), marine loading arms, MLA) is an articulated metal pipeline with the components necessary for its operation, which provides compensation for vessel vibrations caused by tidal characteristics of the water area, wind and wave loads, changes in the ship's draft during loading and unloading operations, as well as designed for loading and unloading oil and oil products, liquid chemicals, liquefied natural gases (LNG), oils into the ship - tanker and / or removal of steam-air mixtures during loading and unloading operations.

In the claimed technical solution, a hinge (swivel) is implemented, which has small dimensions of the working length in the axis, which provides a smaller lever on the boom and, consequently, a smaller effect of the radial force.

The hinge has two structural flanges with a collar for welding to the pipeline, which provides an easy way to mount the hinge, both during production and during operation on the stander. The material of the flanges can be similar to the material of the pipeline, which simplifies the welding technology in production.

In FIG. 2 and 3 show a cassette-type hinge. By separating the flanges with special clamps, which are mounted on a hinge in the bolt holes (24), it is possible to replace not only the primary (6) and secondary (7) seals, anti-extrusion ring (8) and seals (10, 11, 17), but also the joint without disassembly stander or other overall equipment, the key part of which is a swivel joint.

The hinge has installed sealing rings (9) dividing the hinge into separate zones. O-rings prevent lubricant from entering the area of the ball raceways into the joint leakage inspection area, as well as the pumped product or the environment (water, ice, dirt) into the area of the ball raceways.

The hinge has an inspection hole (13) for leakage with a plug. If necessary, the plug can be replaced with a leak sensor of the transported product;

The hinge has a primary (6) and a secondary (7) seal on the side of contact with the transported product with an anti-extrusion ring (8) installed between them (hereinafter referred to as seals on the side of the transported product), which ensures sliding between the rotor and the stator and the correct fit of the seals without distortions.

The primary seal is the main seal that comes into contact with the transported product flowing inside the pipeline and the hinge, and ensures the tightness of the hinge at the given pressure parameters.

The secondary seal acts as an auxiliary seal in case of leakage of the first seal, and also prevents the ingress of the external environment and lubricant from the area of the raceways to the primary seal.

The material, type and shape of the primary and secondary seals are selected individually depending on the transported product, pressure and operating temperature.

The installation location of the seals: parallel to the hinge axis, as shown in figure 2, combined - perpendicular and parallel, as shown in figure 3, or perpendicular to the hinge axis is selected individually depending on the acting loads on the hinge (axial and / or radial), product being transported, flow rate, pressure/vacuum, operating temperatures, as well as ease of installation and maintenance at the installation site. In this case, it is possible to use only the primary seal, which is also selected individually. The shape of the anti-extrusion ring is chosen in accordance with the seals used and the purpose of the ring. The rotor and stator of the hinge have special lodgements for installing seals according to their shape and operating conditions. The hinge stator has a special protrusion-shutter (18), which is adjacent to the hinge flange with a small gap, thereby protecting the seal from damage by possible abrasive, hard particles inside the flow, the influence of the flow velocity itself on the seal and directs the fluid product into the gap, thereby distributing pressure directly on the seal, which ensures the correct operation of the seal. In the event of a vacuum in the pipeline, the protrusion-shutter (18) prevents the seals from leaving their cradles and the hinge does not lose its tightness.

The hinge has plug fittings with lubricators (12) corresponding to the number of ball raceways. Dismantling and installation of rolling balls in the joint is carried out through the holes on which the plugs (12) are installed. Disassembly of the hinge (disconnection of the rotor from the stator) is carried out after removing all the balls from the raceways, respectively, the process of assembling the hinge is carried out with the initial installation of the balls through the holes (12) followed by the installation of plug fittings. Lubricants are used to add lubricant to the ball raceway.

The hinge used with liquid or gaseous products (Fig. 3) having cryogenic temperatures (liquefied natural gas - LNG) has a special channel (15) for supplying gaseous nitrogen - N2 or other inert gas under pressure into the cavity (22) of the ball raceways, and also into the cavity (22) of the zone of the primary (6), secondary (7) seals and the ring (8). Considering that nitrogen is supplied at a temperature higher than or at least comparable to the environment, which is several times higher than the cryogenic temperature, this results in the heating of the seals and their additional compression from the internal cavity of the hinge, which increases the sealing characteristics of the seals, prevents condensation, freezing and ice formation, thus preventing deformation of the hinge and raceways, has a lubricating effect on the raceways of the balls, maintains the existing lubrication of the hinge due to a warmer nitrogen flow, ensures the capture, entrainment of natural gas in case of slight depressurization of the seals (6, 7) and ingress of gas into the cavity (22) of the hinge, thus ensuring the neutralization of explosive concentrations of natural gas. The nitrogen supply channel can enter the area of the seals (10 and 17) of the stator and the stator flange (4), as shown in Fig.3. Nitrogen - N2 is supplied through the fitting on the stator (14), passes through the channel (15), enters the cavity of the raceway zone (5) and the cavity of the seal zone (6, 7 and ring 8) and the seal zone (10 and 17). Passing through the cavities of these zones, nitrogen enters the channel and fitting (16) for the exit of nitrogen - N2 on the rotor.

Material, design, shape, type, number of seals (6, 7 and ring 8), as well as seals (9, 10, 17) for hinges and flanges operating at cryogenic temperatures, are selected individually in accordance with the temperature of the transported product, ambient temperature environment, pressure, flow rate, characteristics of the seals themselves.

Flanges (3, 4), rotor (1) and stator (2) for joints operating at cryogenic temperatures are made of stainless steels, the choice of grade of which is determined each time individually and is due to the ability to withstand heavy loads at cryogenic temperatures without embrittlement of the material, and also positive temperatures.

The hinge has at least two parallel "V"-shaped arch-type raceways (Fig. 4). Each raceway is formed by two grooves of rolling balls of the arch type of the same shape located in the same plane opposite each other. One groove is on the rotor, the other on the stator. Thanks to this technical solution of the raceways (5), the ball (20) has four points of contact (21) with the raceway, that is, two points of contact with the rotor groove and two points of contact with the stator groove. At the same time, the ball in the raceway is constantly loaded at all four points of contact, due to which the hinge has a large bearing capacity, as shown in the diagram of reactions from the action of an external radial force or an external axial force on the ball in the “V”-shaped track rolling arch type (Fig. 5). The formulas for the reaction from the action of a radial or axial force on a ball are given below:

RrO 1 =Rr02=Fro/(cos45 *2); RaO 1 =Ra02=Fao/(cos45 *2)

In the example shown in FIG. 5 and the formulas show the optimal location of the raceways with an angle of 45 degrees. However, if it is known in advance which loads (axial or radial) will act on the hinge, it is possible to increase the bearing capacity of the hinge by changing the angle of the contact point of the track ball. In particular, a sharper angle will allow the hinge to withstand higher radial loads.

Thanks to the technical solution of the hinge with at least two parallel “Y”-shaped arch-type raceways (Fig. 4) and with heat treatment of the surface to a hardness of at least 60 HRC, the hinge can be used in self-supporting structures of a stander or other similar overall equipment, which will significantly reduce the weight of all equipment, labor intensity and cost of equipment during production and subsequent maintenance. The equipment can be used on lightweight berthing structures or on watercraft.

Thanks to the technical solution of the hinge with a "V"-shaped arch-type raceway (Fig. 4), the hinge can be made not only from structural alloy steels subjected to heat treatment in order to increase the hardness of the raceway, but also with softer steels, for example, with stainless steels used for chemical, food or products at cryogenic temperatures.

The claimed technical solution provides for the use of a swivel joint in the design of loaders, loading, loading, reloading sleeves (levers), articulated pipelines and manipulators and other loading and unloading installations for the shipment of oil, oil products, liquid chemical products, liquefied natural gas (LNG), gas condensate and other liquid and gaseous (including boil-off gas) products, has increased bearing capacity due to the “U”-shaped arch-type raceway, including the ability to withstand large axial and radial loads, ensures tightness at a given pressure (vacuum ) and cryogenic temperatures of a liquid or gaseous product. The cassette type of the hinge provides the ability to dismantle and replace the gaskets of the hinge and the ability to dismantle and replace the rotor and stator of the hinge assembly without disassembling the booms and other structures of the above equipment, as well as reduce material consumption and labor intensity in production, which affects the cost of all equipment, part of which hinge is.

Thanks to the technical solution of the hinge with at least two parallel "V"-shaped arch-type raceways (Fig. 4) and with a surface hardness of at least 60 HRC, the hinge can be used in self-supporting structures of a stander or other similar overall equipment, which will significantly reduce the weight of the entire equipment, labor intensity and cost of equipment during production and subsequent maintenance. Equipment with this hinge can be used on lightweight berthing structures or on watercraft.

Thanks to the technical solution of the cassette-type hinge and with a “U”-shaped arch-type raceway (Fig. 4), the hinge can be made not only from structural alloy steels heat treated to increase the hardness of the raceway, but also with softer steels such as stainless steels used for chemical, food or cryogenic temperature products. Thanks to the technical solution of the hinge with the use of purging the hinge with nitrogen - N2 or other inert gas, cassette type and with a "Y"-shaped raceway, the hinge is applicable for products with cryogenic temperatures.

Thanks to the technical solution of the protrusion-shutter (18) between the stator and the flange, as well as the location of the seals on their cradles inside the hinge body, an increased durability of the seals is ensured using their full characteristics.

The swivel joint fully meets the requirements:

- OSIMF "International Maritime Forum of Oil Companies". "Design and construction specification MARINE STENDERS"; - ISO 16904:2016 "Oil and gas industry - Design and testing of offshore LNG transfer arms for conventional onshore terminals";

- STO Gazprom 2-3.4-1255-2021 “Infrastructure for the production, storage and shipment of liquefied natural gas. Stender equipment. General technical conditions".

Claims

Claim

1. Swivel joint of pipelines, containing a hinge having two structural flanges and two housings, each of which is made with at least two parallel ball raceways, while one of the housings acts as a stator, the other rotor, characterized in that the ball raceway is made in the “V”-shaped arch type, while in the stator and rotor housing there is a channel for supplying inert gas to the hinge cavity, and the seals themselves on the side of the transported product are located inside the hinge behind the lug-gate, and the hinge itself has an inspection hole.

2. The swivel joint of pipelines according to claim 1, characterized in that the ball has four points of contact with the “V”-shaped arched raceway, that is, two points of contact per groove of the rotor and stator.

3. Swivel connection of pipelines according to claim 1, characterized in that the rotor and stator assembly are bolted between two structural flanges and form a cassette-type hinge.

4. Swivel joint of pipelines according to claim 3, characterized in that structural flanges can be used with a collar for welding to pipelines or without a collar for welding.

5. Pivot connection of pipelines according to claim 1, characterized in that the inert gas is fed into the channel through a fitting located on the stator, then through the channel inside the stator it is supplied to the hinge cavity in three places: the zone of seals on the side of the transported product, the zone of the ball raceways and the zone of flange seals and is removed from the hinge cavity through the channel and fitting located on the rotor.

6. Swivel joint of pipelines according to claim 1, characterized in that the inner cavity of the hinge is divided into at least two zones by sealing rings.

7. Swivel joint of pipelines according to claim 1, characterized in that a leak detection sensor can be installed in the inspection hole.

8. Swivel joint of pipelines according to claim 1, characterized in that the product being transported is: oil, oil products, liquid chemical products, liquefied natural gas, gas condensate, boil-off gas and other liquid, gaseous and fluid products.