Steel plate sealing structure of underground high-pressure gas storage

Abstract

The utility model provides a steel plate sealing structure of an underground high-pressure gas storage. The steel plate sealing structure of the underground high-pressure gas storage comprises a gas storage steel pipe, an inner stiffening ring and backfill plain concrete, the gas storage steel pipe is buried underground, and the inner stiffening rings are welded in the gas storage steel pipe at equal intervals; the outer surface of the gas storage steel pipe is a smooth surface, and the backfill plain concrete is arranged on the periphery of the gas storage steel pipe. According to the underground high-pressure gas storage steel plate sealing structure and the design method, the problems that in the prior art, construction is complex, and the working space is narrow are solved, and the effects that the work amount is reduced, construction is simplified, the working environment is excellent, the external pressure bearing capacity is high, and the stress condition is good are achieved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to compressed air energy storage power station underground high pressure gas storage design technical field, specifically relates to a kind of underground high pressure gas storage steel plate sealing structure. BACKGROUND

[0002] Compressed air energy storage power station underground high pressure gas storage, by compressed air energy storage, i.e. high pressure air medium energy storage. The leakage of high pressure gas storage high pressure air can affect power generation efficiency, therefore, need to ensure that the compressed air in high pressure gas storage can only have a small leakage. Due to the operating environment of high pressure gas storage is high pressure, high temperature or large temperature difference, temperature and pressure repeated cycle, under this condition, to make the leakage of compressed air in high pressure gas storage meet the requirements, the permeability coefficient of sealing material needs to be low enough, and has strong fatigue resistance and good recovery. Steel is the main sealing material of compressed air energy storage power station underground high pressure gas storage at present because of high strength, good plasticity and toughness, impact resistance, reliable performance, easy to process into plate, profile and wire, good welding and riveting performance.

[0003] High pressure gas storage hole section is large, and the internal pressure is high. The surrounding rock of the cavern is the main bearing body of the internal pressure. The thickness of the steel lining is usually thin. When the high pressure gas storage is inspected and emptied, the external water pressure directly acts on the outer surface of the steel lining. The external pressure resistance of the large-diameter thin smooth pipe is very limited. In order to ensure the stability of the steel lining during the construction of the high pressure gas chamber and during the inspection, and to prevent instability under the action of external water pressure, the design concept of the pressure steel pipe of the hydropower station is used to arrange the stiffening ring outside the steel lining. The radial clearance between the pipe wall of the steel pipe and the surrounding rock is determined according to the construction method and structure, and is generally 600mm.

[0004] The steel lining adopts an external stiffening ring structure, which has the problems of complex construction, high cost, and narrow working space between the steel lining and the rock wall. UTILITY MODEL CONTENTS

[0005] In view of the defects of the prior art, the utility model provides an underground high pressure gas storage steel plate sealing structure, which can effectively solve the above problems.

[0006] The technical scheme adopted by the utility model is as follows:

[0007] The utility model provides an underground high pressure gas storage steel plate sealing structure, which comprises a gas storage steel pipe (1), an internal stiffening ring (2) and backfilling concrete (3).

[0008] The gas storage steel pipe (1) is buried underground, and the internal stiffening ring (2) is welded at equal intervals in the inside of the gas storage steel pipe (1). The outer surface of the gas storage steel pipe (1) is a smooth surface, and the backfilling concrete (3) is arranged on the outer periphery of the gas storage steel pipe (1).

[0009] Preferably, the diameter of the gas storage steel pipe (1) is 10-15 meters; the wall thickness of the gas storage steel pipe (1) is 18-22 mm; the spacing of the inner stiffening ring (2) is 1-2 meters; and the thickness of the inner stiffening ring (2) is 18-22 mm.

[0010] Preferably, the thickness of the backfill concrete (3) is 300-400 mm.

[0011] The underground high-pressure gas storage steel plate sealing structure provided by the utility model has the following advantages:

[0012] The utility model provides an underground high-pressure gas storage steel plate sealing structure, solves the problem of complex construction, narrow operation space and the like in the prior art, and achieves the effects of reducing engineering quantity, simplifying construction, optimizing operation environment, improving external pressure bearing capacity, and good stress condition. BRIEF DESCRIPTION OF DRAWINGS

[0013] Fig. 1 The underground high-pressure gas storage steel plate sealing structure provided by the utility model has the following advantages:

[0014] Fig. 2 The underground high-pressure gas storage steel plate sealing structure provided by the utility model has the following advantages:

[0015] Fig. 3 The underground high-pressure gas storage steel plate sealing structure provided by the utility model has the following advantages:

[0016] Fig. 4 The underground high-pressure gas storage steel plate sealing structure provided by the utility model has the following advantages:

[0017] 1, gas storage steel pipe; 1-1, gas storage steel pipe outer wall; 2, inner stiffening ring; 3, backfill concrete. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical schemes and beneficial effects solved by the utility model more clearly understood, the utility model is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the utility model and do not limit the utility model.

[0019] The utility model provides an underground high-pressure gas storage steel plate sealing structure, solves the problem of complex construction, narrow operation space and the like in the prior art, and achieves the effects of reducing engineering quantity, simplifying construction, optimizing operation environment, improving external pressure bearing capacity, and good stress condition.

[0020] The utility model provides a kind of underground high-pressure gas storage steel plate sealing structure, it is adjusted to steel pipe inner wall by traditional arrangement in the outer stiff ring of steel pipe outer wall, and outer stiff ring structure becomes inner stiff ring structure.Specifically, the inner wall of traditional hydropower station pressure steel pipe is the flow part of water flow, and the flow rate is usually 4m / s~11m / s, to ensure the smoothness of water flow, the inner wall of hydropower station pressure steel pipe needs to be smooth, and stiff ring can only be arranged on the outside of pipe wall.The utility model carries out research on underground high-pressure gas storage steel plate structure, and high-pressure gas is stored in underground high-pressure gas storage, and the volume of gas storage is fixed, and air mainly flows at inlet / outlet port.There is a big difference between the working scene of underground high-pressure gas storage and hydropower station pressure steel pipe, and the stiff ring can be arranged on the inner wall of steel pipe.The inner stiff ring can also increase the stiffness of steel pipe and improve the ability to resist external pressure, and the mechanical effect is similar to that of outer stiff ring.The distance between inner stiff ring and steel pipe ring joint should not be less than 3 times the thickness of steel pipe wall, and should not be less than 100mm;The butt weld of inner stiff ring is a second class weld.

[0021] Reference Figs. 1 to 4 The utility model provides a kind of underground high-pressure gas storage steel plate sealing structure, including gas storage steel pipe 1, inner stiff ring 2 and backfilling concrete 3;

[0022] The gas storage steel pipe 1 is buried in the ground, and the inner stiff ring 2 is welded at equal intervals in the inside of the gas storage steel pipe 1;The outer surface of the gas storage steel pipe 1 is a smooth surface, and the backfilling concrete 3 is arranged on the outer periphery of the gas storage steel pipe 1.

[0023] As a preferred mode, the diameter of the gas storage steel pipe 1 is 10~15 meters;The wall thickness of the gas storage steel pipe 1 is 18mm~22mm;The spacing of the inner stiff ring 2 is 1m~2m;The thickness of the inner stiff ring 2 is 18mm~22mm.The thickness of the backfilling concrete 3 is 300mm~400mm.

[0024] The utility model also provides a kind of design method of underground high-pressure gas storage steel plate sealing structure, comprising the following steps:

[0025] Step S1, when determining gas storage working condition, the high-pressure gas internal pressure range borne by underground high-pressure gas storage steel plate sealing structure and surrounding rock together;

[0026] Step S2, using three-dimensional finite element numerical calculation method, to determine the gas storage steel pipe wall thickness t that meets the high-pressure gas internal pressure range;

[0027] Step S3, to carry out the anti-external pressure stability review analysis of underground high-pressure gas storage steel plate sealing structure:

[0028] Step S3.1, initially set the initial value of inner stiff ring spacing l;

[0029] Step S3.2, the radial underground water external water pressure P that the underground high-pressure gas storage steel plate sealing structure can bear in the maintenance working condition is obtained when the gas storage steel pipe wall thickness t and the inner stiffening ring spacing l are adopted by using the following formula:

[0030]

[0031] In the formula:

[0032]

[0033] E—elastic modulus of the steel material adopted by the gas storage steel pipe;

[0034] μ—Poisson's ratio of the steel material;

[0035] r—inner radius of the gas storage steel pipe;

[0036] n—buckling half-wave number;

[0037] E ′ —first intermediate variable;

[0038] λ—second intermediate variable;

[0039] η—third intermediate variable;

[0040] wherein the inner radius r of the gas storage steel pipe is determined according to the construction engineering requirement;

[0041] Step S3.3, whether the radial underground water external water pressure P that the underground high-pressure gas storage steel plate sealing structure can bear in the maintenance working condition obtained can meet the design requirement is judged; if yes, step S4 is executed; if no, the inner stiffening ring spacing l is adjusted, and step S3.2 is returned;

[0042] Step S4, the structure parameters of the designed underground high-pressure gas storage steel plate sealing structure are output, including the gas storage steel pipe wall thickness t, the inner radius r of the gas storage steel pipe and the inner stiffening ring spacing l.

[0043] Specifically, due to the large diameter of the underground high-pressure gas storage cavern, the thin thickness of the sealing steel plate of the steel pipe, and the different design concept of the gas storage steel pipe from the traditional pressure steel pipe of the hydropower station, in the specific design, firstly, the three-dimensional finite element numerical calculation method is adopted to determine the thickness of the steel pipe wall based on the design mode that the steel plate sealing structure and the surrounding rock jointly bear the high-pressure gas internal pressure; then, the external pressure stability review analysis of the steel pipe structure is carried out. When the gas storage is in normal operation, the internal gas pressure is much greater than the external groundwater pressure, and the buckling instability of the steel pipe under the action of the external groundwater pressure can be ignored in normal operation; however, in the maintenance and other working conditions, the external groundwater pressure of the steel pipe may be greater than the internal pressure of the steel pipe, and the steel pipe may be buckled and unstable, so the external pressure stability review of the steel pipe structure is required. Finally, the thickness of the steel pipe wall, the interval of the internal stiffening ring, the internal radius of the gas storage steel pipe and the external pressure bearing capacity are determined by comprehensively considering the calculation results of the steel pipe structure under the action of the internal pressure and the external pressure stability review results.

[0044] Compared with the prior art, the underground high-pressure gas storage steel plate sealing structure and the design method have the following advantages:

[0045] 1. The construction is greatly simplified, and the construction efficiency is improved:

[0046] The diameter of the steel pipe is usually more than 10m, the structure of the internal stiffening ring is adopted, the welding work is mainly completed in the steel pipe, the construction space is spacious, and the deficiency of welding the external stiffening ring in the narrow space between the steel pipe outside and the rock wall in the traditional scheme is solved.

[0047] 2. The thickness of the backfilling concrete outside the steel pipe and the excavation section of the cavern are reduced, and the engineering quantity is significantly reduced:

[0048] According to the relevant construction specification requirements, when welding work is required outside the pipe after the steel pipe is in place, the distance from the outer edge of the steel external stiffening ring to the rock wall should be greater than 300mm, and the engineering quantity is large. The internal stiffening ring structure is adopted in the utility model, and the main welding work of the internal stiffening ring structure is carried out in the steel pipe, and the external wall of the steel pipe is only arranged with the wall-attached drainage angle steel. The thickness of the backfilling concrete can be reduced to 300mm, and the excavation section is correspondingly reduced.

[0049] 3. The stress condition is good:

[0050] The external wall of the steel pipe is smooth, and under the action of high-pressure gas, the steel pipe can more uniformly transmit the internal pressure to the backfilling concrete and the surrounding rock.

[0051] 4. The technical route of the utility model is clear, the construction method is simple, the operability is strong, the technical economy is superior, and the utility model has strong engineering practical value.

[0052] The above merely is preferred implementation manner of the present application, it should be pointed out, for ordinary skilled person in the technical field, on the premise of not departing from the principle of the present application, can also make several improvements and refinements, these improvements and refinements also should be regarded as the protection scope of the present application.

Claims

1. A steel plate seal structure for underground high-pressure gas storage, characterized by, It comprises a gas storage steel pipe (1), an inner stiffening ring (2) and backfilling concrete (3). The gas storage steel pipe (1) is buried underground, and the inner stiffening ring (2) is welded at equal intervals in the interior of the gas storage steel pipe (1); the outer surface of the gas storage steel pipe (1) is a smooth surface, and the backfilling concrete (3) is arranged on the outer periphery of the gas storage steel pipe (1).

2. The underground high-pressure gas storage steel plate seal structure according to claim 1, characterized in that, The diameter of the gas storage steel pipe (1) is 10-15 m; the wall thickness of the gas storage steel pipe (1) is 18-22 mm; the interval of the inner stiffening ring (2) is 1-2 m; and the thickness of the inner stiffening ring (2) is 18-22 mm.

3. The underground high-pressure gas storage steel plate seal structure according to claim 1, characterized in that, The thickness of the backfilling concrete (3) is 300-400 mm.

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