CN211118222U - Flexible flare pipeline system based on expansion joint compensation - Google Patents

Abstract

A flare pipeline flexible system based on expansion joint compensation comprises a flare header pipe, a reaction device and a liquid separation tank which are arranged in an overhead manner, wherein the reaction device and the liquid separation tank are connected to the flare header pipe which consists of a straight pipe section and a return bend pipe section; the method solves the difficult problem of the layout design of the flare pipeline of the large-scale energy chemical device, improves the safety and reliability of the flare pipeline, reduces the investment, and improves the economical efficiency of a flare pipeline system by more than 30 percent.

Description

Flexible flare pipeline system based on expansion joint compensation

Technical Field

The utility model relates to an energy chemical plant's torch pipeline flexible compensation technique, what specifically says so is a torch pipeline flexible system based on expansion joint compensation.

Background

The flare system is generally composed of four parts, namely a flare gas liquid separating tank, a flare gas water sealing tank, a flare and a flare pipeline. The torch system has the main functions of collecting combustible and toxic gas discharged by the energy chemical production device in normal production, start/stop and accident states through a torch facility and safely burning the gas, so that the safety of the device is ensured, and the pollution of the discharged gas to the atmospheric environment is reduced. The pipe network of the flare system is the foundation of safe operation of the discharge device, namely, the flare pipeline is the last line of defense of the energy chemical device, and the safety and the reliability of the flare pipeline are very important.

The flare tip is typically hundreds or even thousands of meters in length due to the need to deliver the exhaust gases to a safe area outside the device for combustion evacuation. The energy chemical device has complex medium components and high flow speed in the emptying torch pipe. The flare pipeline is generally laid overhead and arranged together with a process and a public steam pipeline and the like, and the flare pipeline is laid on the same frame. Flare lines are subject to a wide range of operating temperatures, pressures, and stress variations resulting from such wide range of operating conditions, and the lines are subject to complex stresses. Besides the stress caused by pressure and temperature changes, the flare pipeline also has the impact force generated by opening and closing of a valve and the condensate in the flare pipeline on a pipe network, so the design of the fixing, guiding and supporting system of the flare pipeline is complicated. The energy chemical device has large scale and large discharge amount, and the corresponding flare pipeline has large diameter and large rigidity, thereby reducing the stress of the pipeline, meeting the flexibility requirement and the stability requirement of the pipeline, improving the shock and vibration resistance of the pipeline and the bracket thereof, ensuring the safety of the system, and being necessary for carrying out cold and thermal deformation flexible compensation on the flare pipeline. The current common method adopts pi-shaped bending natural compensation to solve the stress and deformation generated by thermal expansion, namely the natural elastic deformation of the pipeline material is mainly used for absorbing the thermal expansion. Along with the landing of the planning of a plurality of 'refining and chemical integration' bases in China, petrochemical industry, coal chemical industry and other petrochemical and post-derivative production devices have the characteristics of enlarged production scale, combined construction and joint production and centralized supply of public works, the diameter of a torch pipeline is larger and larger, the maximum diameter reaches phi 3m, because the diameter of the pipeline is larger, the lateral extension of the n-shaped bend compensation bend pipe is about 100-120 m generally, a large amount of raw materials are economically consumed, a large amount of land is occupied, meanwhile, a large amount of steel structure supports are used for restraining the shrinkage deformation of the pipeline, and the investment cost is high; in the aspect of safety and stability, as shown in fig. 1, pi-shaped bending compensation is adopted, so that the pressure drop of the pipeline is large, the positions with high pipeline stress are more, the stress of the bracket is large, and the flexibility and the reliability of the pipeline are low. Therefore, the arrangement and design difficulty of the large-caliber flare pipeline is high, and the problem in the petroleum and petrochemical design field is formed.

SUMMERY OF THE UTILITY MODEL

For solving the technical problem, the utility model provides a torch pipeline flexible system based on expansion joint compensation solves the design difficult problem of arranging of large-scale energy chemical plant torch pipeline, improves the fail safe nature of torch pipeline, reduces the investment simultaneously, improves torch pipeline system's economic nature more than 30%.

In order to realize the technical purpose, the adopted technical scheme is as follows: a flare pipeline flexible system based on expansion joint compensation comprises a flare header pipe, a reaction device and a liquid separation tank which are arranged in an overhead manner, wherein the reaction device and the liquid separation tank are connected to the flare header pipe which consists of a straight pipe section and a return bend pipe section;

the balance corrugated pipe of the explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint is provided with a balance corrugated pipe explosion-proof support core cylinder close to the inner side of the balance corrugated pipe;

the composite expansion joint of the universal hinge and pull rod comprises two groups of corrugated pipes with middle pipes, two single universal hinge assemblies and a plurality of pull rod assemblies, wherein the two single universal hinge assemblies and the plurality of pull rod assemblies are fixedly arranged on the outer sides of the two groups of corrugated pipes with the middle pipes, two ends of the two single universal hinge assemblies and two ends of the plurality of pull rod assemblies are respectively connected with two end pipe assemblies of the two groups of corrugated pipes with the middle pipes, and balancing rings are sleeved on the two groups of corrugated pipes.

The middle fixed pipe racks are arranged at the two ends of the straight pipe section, and at least three guide pipe racks are arranged at the positions close to the explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint.

The bending pipe section is L type pipe section or Z type pipe section.

The explosion-proof straight-through external pressure straight pipe pressure balance expansion joint for the compensation of the straight pipe section of the flare pipeline has the advantages that the corrosion resistance of the expansion joint can be improved because the discharge medium is corrosive, an external pressure corrugated pipe and a flare discharge gap are selected, and the surface of the corrugated pipe is not contacted with the possible condensate; meanwhile, in order to improve the safety of the corrugated pipe, the external pressure circumferential stability of the corrugated pipe needs to be tested according to the size of the diameter to carry out displacement-pressure stability test in a stretching displacement state so as to determine the safety coefficient of the external pressure circumferential stability of the corrugated pipe and meet the safety and reliability of flare pipeline discharge.

A universal hinge pull rod composite expansion joint for compensation of a flare pipeline bend section is mainly installed at the bend section of a branch liquid tank and a water seal tank of a flare pipeline, a corrugated pipe adopts an internal pressure reinforced U-shaped corrugated pipe reinforced by a balance ring, a stress structural member of the expansion joint is two pairs of stress components of a universal hinge and a compound pull rod, the double insurance of the stress structural member can improve the impact shock resistance of an internal medium, and the safety and reliability of the pipeline under the condition of high flow rate discharge of the flare medium can be greatly improved.

The explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint and the universal hinge pull rod composite expansion joint for flare pipeline compensation are specially designed according to the characteristics of flare pipelines, are different from the expansion joint design requirements in other fields, and can ensure the safety and reliability of the flare pipelines.

The utility model has the advantages that:

1. the expansion joint compensation is adopted for the flare pipeline, so that pipeline stress and pipeline support load can be effectively reduced, the safety and reliability of a pipe network are improved, a medium can be directly discharged from the straight pipe section by adopting the expansion joint compensation, the diameter of the pipeline can be effectively reduced, the construction cost can be reduced by 30-40% by adopting the expansion joint compensation ratio n-bend compensation, the flare pipeline and other public engineering pipelines can be conveniently laid in a common frame, the construction operation amount of field hoisting, welding, nondestructive testing and the like can be reduced, the consumption of resources such as water for a hydraulic test, occupied area and the like is reduced, and the flexible system adopting the expansion joint compensation for the flare pipeline has obvious economic advantages.

2. The utility model discloses an explosion-proof through external pressure straight tube pressure balance type expansion joint can resist the design pressure below 3 times and does not produce the blasting and leak. Compared with the common compound pull rod type expansion joint with the balance ring protection, the universal hinge pull rod compound expansion joint has the advantages that two sets of single type universal hinge stress components are additionally arranged outside two sets of reinforced U-shaped corrugated pipes, the two sets of stress components can meet the requirement that the expansion joint compensates for transverse displacement, when one stress component fails, the other pair of stress components can continuously play a compensation role, pressure thrust generated by the corrugated pipes is restrained, and double insurance of the stress components is formed. The straight pipe section adopts explosion-proof straight-through type external pressure straight pipe pressure balance type expansion joint compensation, and the elbow pipe section adopts universal hinge pull rod composite type expansion joint compensation with balance ring protection, so that the requirements of high medium flow velocity, strong shock resistance, reliable discharge and the like of flare pipeline discharge can be better met.

Drawings

FIG. 1 is a schematic diagram of a prior art structure;

FIG. 2 is a schematic structural view of the present invention;

FIG. 3 is a schematic diagram of the structure of a straight pipe section according to the present invention;

fig. 4 is a structural schematic diagram of an L type pipe section according to the present invention;

FIG. 5 is a schematic view of the Z-shaped pipe section structure of the present invention;

FIG. 6 is a schematic view of the structure of the explosion-proof straight-through external pressure straight pipe pressure balance expansion joint of the present invention;

FIG. 7 is a schematic structural view of the universal hinge pull rod composite expansion joint of the present invention;

in the figure: 1. a main reaction device, 2, a torch main pipe, 3, a guide pipe frame, 4, an explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint, 5, a middle fixed pipe frame, 6, reaction devices A, 7, reaction devices B, 8, reaction devices C, 9, a universal hinge pull rod composite expansion joint, 10, a liquid separating tank, 11, a water seal tank, 12, a torch head, 13, a plane guide pipe frame, 21, a straight pipe section, 22, a bend pipe section, 01, an end pipe, 02, a balance wave end ring component 03, a working wave end ring component, 04, a balance corrugated pipe, 05, an outer pipe component, 06, a balance corrugated pipe connecting pipe, 07, a balance wave connecting pipe supporting ring plate, 08, a working corrugated pipe, 09, a working corrugated pipe outer pipe, 010, a guide cylinder A, 011, a balance corrugated pipe explosion-proof supporting core cylinder, 012, a core cylinder reinforcing rib, 013, an end pipe component, 014, a nut, 015, a spherical gasket, 016. conical washer, 017, balanced ring, 018, bellows, 019, pull rod, 020, middle pipe, 021, draft tube B, 022, long hinge plate, 023, long hinge plate fixed riser, 024, round pin axle, 025, round pin axle retaining ring, 026, universal ring, 027, short hinge plate.

Detailed Description

As shown in figure 2, a torch pipeline flexible system based on expansion joint compensation, including built on stilts torch house steward 2 of laying, reaction unit and knockout drum 10 are connected on torch house steward 2, reaction unit can set up a plurality ofly as required, the medium that reaction unit discharged gets into torch house steward 2, get into the knockout drum 10 through torch house steward 2 in, torch house steward 2 comprises straight tube section 21 and return bend section 22, the system still includes explosion-proof through type external pressure straight tube pressure balance expansion joint 4 and the compound expansion joint of universal hinge pull rod 9, the thermal displacement of straight tube section 21 is compensated by explosion-proof through type external pressure straight tube pressure balance expansion joint 4, the thermal displacement of return bend section 22 is compensated by the compound expansion joint of universal hinge pull rod 9.

As shown in fig. 6, compared with the common structure of the prior art, the explosion-proof supporting core barrel 011 of the balance corrugated pipe and the core barrel reinforcing ribs 012 thereof are added to the explosion-proof straight-through external pressure straight pipe pressure balance type expansion joint, and other structures are consistent with the prior art.

Under the working state of the external pressure corrugated pipe, the external part of the corrugated pipe is filled with a medium, and under the abnormal working conditions of over-temperature, over-pressure and the like, the failure mode is external pressure circumferential instability, and the current domestic and foreign expansion joint standards only stipulate the blasting test method and evaluation results of the internal pressure corrugated pipe. Because the balance corrugated pipe deforms to the inner cavity after being unstable in an external pressure state, the balance corrugated pipe is in various forms, and if the balance corrugated pipe is not limited, the balance corrugated pipe can be broken when the deformation exceeds a certain degree under the continuous action of pressure. The utility model discloses an utilize the thin wall component characteristic of bellows, it sets up the explosion-proof support core section of thick bamboo 011 of balanced bellows and core section of thick bamboo strengthening rib 012 to be close to its internal diameter at balanced bellows 04 inboard, it is injectd to its balanced bellows inward deformation that receives the external pressure, make balanced bellows can not produce the blasting under the design pressure effect below 3 times and tear, work bellows 08 is nearer because of its internal diameter apart from the distance of expansion joint end pipe 01, can play the guard action, the structure of external pressure axial expansion joint is rather unanimous, the safe application of many years's external pressure axial expansion joint, its security has been proven. Therefore, the expansion joint has an explosion-proof leakage function for resisting the design pressure less than 3 times, and when a torch is discharged, the expansion joint guide cylinder A010 shields the internal structure gap of the expansion joint, so that a medium can pass through the expansion joint in a straight-through manner.

As shown in fig. 7, compared with the common compound pull rod type expansion joint, the composite expansion joint of the universal hinge pull rod has the advantages that two sets of single universal hinge stressed components are additionally arranged outside two sets of reinforced U-shaped corrugated pipes, the two sets of stressed components can both meet the requirement that the expansion joint compensates for transverse displacement, when one stressed component fails, the other stressed component can play the same role to restrain the pressure thrust generated by the corrugated pipe, and thus the double insurance of the stressed component is formed. The expansion joint consists of a middle pipe 020, a corrugated pipe 018 and an end pipe assembly 013, wherein one end of the corrugated pipe 018 is connected with two ends of the middle pipe 020, the other end of the corrugated pipe 018 is connected with the end pipe assembly 013, and when a torch pipeline is discharged, the medium flow rate is high, particularly, the impact force on the pipeline is large at a turning part, and the safety and the reliability on the expansion joint are high. Therefore, the utility model designs two sets of load bearing structures for carrying out transverse displacement compensation on the turning part of the flare pipeline, the universal hinge pull rod composite expansion joint combines the composite pull rod and two single universal hinge type expansion joint structures,

two sets of single universal hinge assemblies (comprising a short hinge plate 027, a universal ring 026, a pin shaft 024, a long hinge plate 022 and a fixed vertical plate 023 of the long hinge plate) and a plurality of compound pull rod assemblies (comprising a pull rod 019, spherical conical surface gaskets 015 and 016 and a nut 014) are fixedly arranged outside two groups of corrugated pipes with intermediate pipes, two ends of the two sets of single universal hinge assemblies and two ends of the compound pull rod assemblies are respectively connected with two end pipe assemblies 013 of the two groups of corrugated pipes, and a balance ring 017 is sleeved on a corrugated pipe 018 of an internal pressure straight pipe pressure balance expansion joint, so that the combined structure not only can ensure the effective absorption of the transverse displacement generated by a torch pipeline, but also can greatly improve the safety and reliability of the expansion joint.

To the new utility model discloses an explosion-proof through type external pressure straight tube pressure balance type expansion joint of torch pipeline flexible compensation system and have the compound inflation of universal hinge pull rod of balanced ring protection can be better satisfy torch pipeline discharge medium velocity of flow height, shock resistance can the reinforce, discharge requirements such as reliable.

According to the characteristics of a torch pipeline, the explosion-proof straight-through external pressure straight pipe pressure balance type expansion joint corrugated pipe 4 adopts an external pressure U-shaped multilayer structure, and the corrugated pipe of the universal hinge pull rod composite type expansion joint 9 adopts a reinforced U-shaped multilayer structure.

As shown in figure 3, the straight-through external pressure straight pipe pressure balance type expansion joint 4 is applied to compensation of a straight pipe section of a flare pipeline, middle fixed pipe frames are arranged at two ends of the straight pipe section, at least 3 guide pipe frames are arranged at positions close to the expansion joint, and the displacement direction applied to the expansion joint is ensured to be matched with the original design. The spacing of the guide brackets is performed with reference to appendix E of GB/T12777-2019.

As shown in figure 6, necessary measures are taken to avoid water hammer impact caused by accumulated liquid in the expansion joint, an external heat preservation or laying heat tracing system can be adopted, an accumulated liquid discharge port can also be arranged to remove internal condensed liquid in time, and the expansion joint is blocked by a drainage and condensation-discharging screw plug after the cleaning is finished.

As shown in fig. 4 and 5, the elbow section is L type pipeline or Z type pipeline, as shown in fig. 4, the elbow section is used for the 'L' shaped pipe section with the short pipe leg length approximate to the length of the universal hinge pull rod composite expansion joint, and as shown in fig. 5, the elbow section is used for the plane 'Z' shaped pipe section with the middle pipe leg length approximate to the length of the universal hinge pull rod composite expansion joint.

In the accident state of starting and stopping the chemical plant, an emergency and the like, as shown in fig. 2, chemical reaction substances in the main reaction device 1 and other reaction devices A6, B7 and C8 are emergently discharged into the flare header pipe 2, discharged to the flare head 12 through the liquid separating tank 10 and the water sealing tank 11 and burnt and exhausted, so that the system stability and safety of the production device are ensured, and the overpressure accident is prevented. In the discharging process, the temperature of the torch main pipe 2 rises, the thermal expansion amount of the long straight pipe section of the torch main pipe 2 is absorbed by the straight-through external pressure straight pipe pressure balance type expansion joint 4, the pipeline bending pipe section of the pipeline of the torch main pipe 2 entering and exiting the branch liquid tank 10 is compensated by the universal hinge pull rod composite type expansion joint 9, the thermal displacement of the pipeline is absorbed, the thermal stress of the pipeline is reduced, and the safety of the device is protected.

The flare system is a part which is easy to ignite, explode, poisoned by hydrogen sulfide and other accidents, and can meet the flexibility requirement if a traditional tortuous n-shaped bend compensation mode is adopted, but during n-shaped bend compensation, a large number of pipe system elbows exist, during discharge, the flow direction of a medium flowing at high speed is frequently changed in a flare header pipe, the flow resistance is large, large impact force can be generated on each elbow part, even a water hammer phenomenon can be generated when gas-liquid two-phase flow exists, and when flare gas is emptied, impact can be formed due to the increase of resistance to cause the oscillation or instability of an emptying pipe system. The flexible flare pipeline system compensated by the expansion joint in the figure 2 is adopted, and the straight pipe section adopts the straight-through external pressure straight pipe pressure balance type expansion joint 4, so that the flare header pipe 2 can be arranged linearly, the design difficulty of a large-caliber flare pipeline is reduced, the smooth discharge of a discharged medium is favorably ensured, the equivalent length of a pipeline can be reduced, the pressure drop of the pipeline is reduced, and the diameter of the flare header pipe can be reduced; and a universal hinge pull rod composite expansion joint 9 with a balance ring is adopted to compensate at the elbow pipe section of the flare header pipe 2 entering and exiting the liquid separation tank 10. The whole torch main pipe 2 is compensated by adopting two constraint expansion joints, namely a straight-through external pressure straight pipe pressure balance type expansion joint 4 and a universal hinge pull rod composite type expansion joint 9 with a balance ring, so that the flexibility and the safety and reliability of a pipeline can be effectively guaranteed. Meanwhile, the flare pipeline and other common engineering pipelines are conveniently laid on a common frame, the occupied area and the construction cost are reduced, and the practical case proves that the construction cost can be reduced by 30-40% by adopting the expansion joint flexible compensation scheme compared with the traditional n-bend compensation scheme, and the economic benefit is obvious.

In the flexible compensation system, the trend of the flare header pipe is not limited to the example, and various trends can be realized according to the arrangement and the scale of the device, but the expansion joint compensation type of the straight pipe section and the elbow pipe section is not changed. The explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint and the universal hinge pull rod composite expansion joint for flare pipeline compensation are specially designed according to the characteristics of flare pipelines, are different from the expansion joint design requirements in other fields, and can ensure the safety and reliability of the flare pipelines.

Claims (3)

1. The utility model provides a flexible system of torch pipeline based on expansion joint compensation, includes built on stilts torch house steward (2) of laying, reaction unit and branch fluid reservoir (10), and reaction unit and branch fluid reservoir (10) are connected on torch house steward (2), and torch house steward (2) comprises straight tube section (21) and turning pipe section (22), its characterized in that: the system also comprises an explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint (4) and a universal hinge pull rod composite expansion joint (9), wherein the explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint (4) is used for flexible compensation of a straight pipe section (21), and the universal hinge pull rod composite expansion joint (9) is used for flexible compensation of a bent pipe section (22);

the balance corrugated pipe (04) of the explosion-proof straight-through external pressure straight pipe pressure balance expansion joint (4) is provided with a balance corrugated pipe explosion-proof support core barrel (011) close to the inner side of the balance corrugated pipe;

the composite expansion joint (9) of the universal hinge pull rod comprises two groups of corrugated pipes (018) with middle pipes (020), two sets of single universal hinge assemblies and a plurality of pull rod assemblies, wherein the two sets of single universal hinge assemblies and the plurality of pull rod assemblies are fixedly arranged on the outer sides of the two groups of corrugated pipes with the middle pipes, two ends of the two sets of single universal hinge assemblies and two ends of the plurality of pull rod assemblies are respectively connected with two end pipe assemblies (013) of the two groups of corrugated pipes with the middle pipes, and two groups of corrugated pipes (018) are sleeved with balance rings (017).

2. A flare line flexibility system based on expansion joint compensation as claimed in claim 1, wherein: the two ends of the straight pipe section (21) are provided with middle fixed pipe frames (5), and at least three guide pipe frames (3) are arranged at the positions close to the explosion-proof straight-through type external pressure straight pipe pressure balance expansion joint (4).

3. A flare line flexible system based on expansion joint compensation as defined in claim 1, wherein the elbow section (22) is L-shaped section or Z-shaped section.

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