Sunken seam damage test device for flexible sealing material of compressed air energy storage underground cavern

Abstract

The invention discloses an air compression energy storage underground cavern flexible sealing material notch damage test device which comprises an air compressor, a booster pump, an air storage tank, an air inlet valve, a pressure control valve, a device body, a manometer and a monitoring instrument which are sequentially connected in a sealed mode through a pipeline, and an air outlet valve is connected to the pipeline between the air inlet valve and the pressure control valve. The device body comprises an air pressure chamber, a concrete mold is placed at the bottom of an inner cavity of the air pressure chamber, a prefabricated crack and a prefabricated hole which are communicated are prefabricated in the concrete mold, and the prefabricated hole is located under the prefabricated crack. The device is simple in structure, safe, reliable and rapid and convenient to test, cracks and holes are prefabricated in the concrete mold, the air inlet rate of the air pressure chamber is accurately adjusted and controlled through the pressure control valve, and the pressure is suddenly reduced due to the volume change of the air pressure chamber before and after the flexible sealing material test piece is damaged. Whether the flexible sealing material test piece is subjected to notch damage or not is judged, and the problem that the state of the test piece in the closed space cannot be observed is ingeniously solved.

Description

Technical Field

[0001] The invention relates to the field of underground energy storage, and in particular to a crack failure test device for a flexible sealing material of a compressed air energy storage underground cavern. Background Art

[0002] Due to the intermittent and volatile characteristics of renewable energy, direct large-scale grid connection will bring a huge impact to the power grid, so corresponding energy storage technology is needed. Compressed air energy storage (i.e. compressed air energy storage) is one of the few large-scale energy storage technologies and has urgent and huge development potential in areas of my country rich in renewable energy.

[0003] As a storage container for high-pressure air, underground caverns play an important role in the operation of compressed gas energy storage power stations, and the key issue in their construction is the sealing of the caverns. Flexible sealing technology is a promising way to seal compressed gas energy storage underground caverns due to its advantages of low cost, good airtightness and strong geological adaptability. The structure of the flexible sealed compressed gas energy storage cavern is a flexible sealing layer, lining and surrounding rock from the inside to the outside. Commonly used flexible sealing layer materials include butyl rubber, nitrile rubber, EPDM rubber, etc. Under the action of high internal pressure, the lining will inevitably crack. After the lining cracks, the flexible sealing layer in direct contact with it is at risk of crack damage. For this reason, it is necessary to explore the relationship between the thickness of the sealing layer and the crack width of the lining under high internal pressure through experiments, so as to provide a theoretical basis for the design of the thickness of the flexible sealing layer of high internal pressure caverns such as compressed gas energy storage caverns. However, there is currently no corresponding test device. Summary of the invention

[0004] In view of the current problem that the crack destruction test of flexible sealing materials under high internal pressure cannot be carried out, the present invention provides a crack destruction test device for flexible sealing materials of compressed air energy storage underground caverns, which has the characteristics of simple structure, safety and reliability, and quick and convenient testing.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: a crack destruction test device for flexible sealing materials of compressed air energy storage underground caverns, comprising an air compressor, a booster pump, an air storage tank, an air inlet valve, a pressure control valve, a device body, a pressure gauge and a monitoring instrument which are sealed and connected in sequence through pipelines, an air outlet valve is connected to the pipeline between the air inlet valve and the pressure control valve, the device body comprises a sealable air pressure chamber surrounded by steel plates, a concrete mold is placed at the bottom of the inner cavity of the air pressure chamber, prefabricated cracks and prefabricated holes are prefabricated in the concrete mold, the prefabricated cracks are arranged at the top of the concrete mold, the length and width of the prefabricated cracks are both smaller than the concrete mold, the prefabricated holes are located directly below the prefabricated cracks, the prefabricated holes are communicated with the prefabricated cracks, and the volume of the prefabricated holes is larger than the volume of the prefabricated cracks;

[0006] Before use, the air is continuously compressed to a specified pressure by an air compressor and a booster pump and stored in an air tank for standby use. Before the test, the four sides of the sheet-like flexible sealing material specimen are fixed to the top surface of the concrete mold by glue, the prefabricated cracks are covered by the flexible sealing material specimen, and the air pressure chamber is sealed to start the crack failure test, that is, open the air inlet valve, close the air outlet valve, adjust the air intake rate of the gas entering the air pressure chamber by the pressure control valve, so that the pressure in the air pressure chamber increases linearly, and monitor and record the pressure changes in the air pressure chamber at different time points in real time by monitoring instruments and pressure gauges, and establish a gas loading curve. When the pressure in the air pressure chamber exceeds the maximum air pressure that the flexible sealing material specimen can withstand, the flexible sealing material specimen will be cracked and damaged. At this time, the air in the air pressure chamber will flow into the prefabricated hole through the prefabricated cracks, causing the pressure in the air pressure chamber to drop suddenly. According to the pressure drop point on the gas loading curve, it is judged at what atmospheric pressure the flexible sealing material specimen is damaged.

[0007] Preferably, the volume of the prefabricated hole is 3-7% of the volume of the inner cavity of the air pressure chamber. If the volume of the prefabricated hole is too small, when the flexible sealing material specimen is damaged by cracking, the pressure drop in the air pressure chamber is not obvious, and the position of the damage point cannot be seen on the gas loading curve; if the volume of the prefabricated hole is too large, it may exceed the bearing strength of the concrete mold. Therefore, the present invention limits the volume of the prefabricated hole to 3-7% of the volume of the inner cavity of the air pressure chamber.

[0008] Preferably, the top of the air pressure chamber is a detachable cover plate, and the cover plate is fixedly connected to the air pressure chamber by a plurality of bolts, the plurality of bolts are evenly spaced around the cover plate, and a sealing ring is provided between the cover plate and the air pressure chamber.

[0009] Compared with the prior art, the present invention has the following advantages: the present invention has the characteristics of simple structure, safety and reliability, and quick and convenient testing for the crack damage test device of the flexible sealing material of the compressed air energy storage underground cavern. The crack damage test device uses an air compressor, a booster pump and an air storage tank as the air source, and cooperates with a pressure control valve to realize the linear increase and precise control of the pressure in the air pressure chamber, providing the required high-pressure environment for the flexible sealing material specimen during the test. In addition, the crack damage test device sets a prefabricated crack on the top of the concrete mold, and sets a prefabricated hole connected to the prefabricated crack directly below the prefabricated crack. The pressure control valve accurately adjusts the air intake rate of the gas entering the air pressure chamber to ensure that the pressure in the air pressure chamber increases linearly. The sudden drop in pressure caused by the volume change of the air pressure chamber before and after the flexible sealing material specimen is destroyed is used to determine whether the flexible sealing material specimen has crack damage, which cleverly solves the problem of being unable to observe the state of the specimen in the confined space. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 Schematic diagram of the structural connection of the seam failure test device in the embodiment (with the cover open);

[0011] Figure 2 For the enlarged Figure 1 Middle AA section view;

[0012] The specific reference numerals in the figure are as follows:

[0013] 1-air compressor; 2-boosting pump; 3-air storage tank; 4-inlet valve; 5-exhaust valve; 6-pressure control valve; 7-device body; 8-pressure gauge; 9-monitoring instrument; 10-steel plate; 11-bolt; 12-sealing ring; 13-air pressure chamber; 14-flexible sealing material specimen; 15-prefabricated crack; 16-prefabricated hole; 17-concrete mold; 18-cover plate. DETAILED DESCRIPTION

[0014] The present invention is further described in detail below in conjunction with the embodiments of the drawings. The devices, equipment or components not limited in the present invention all adopt conventional technical means in the art.

[0015] A crack failure test device for a flexible sealing material of a compressed air energy storage underground cavern according to an embodiment of the present invention is as follows: Figure 1 and Figure 2 As shown, it includes an air compressor 1, a booster pump 2, an air storage tank 3, an air inlet valve 4, a pressure control valve 6, a device body 7, a pressure gauge 8 and a monitoring instrument 9 which are sealed and connected in sequence through pipelines. An air outlet valve 5 is connected to the pipeline between the air inlet valve 4 and the pressure control valve 6. The device body 7 includes a sealable air pressure chamber 13 surrounded by a steel plate 10. A concrete mold 17 is placed at the bottom of the inner cavity of the air pressure chamber 13. A prefabricated crack 15 and a prefabricated hole 16 are prefabricated in the concrete mold 17. The prefabricated crack 15 is arranged on the top of the concrete mold 17. The length and width of the prefabricated crack 15 are both smaller than the concrete mold 17. The prefabricated hole 16 is located directly below the prefabricated crack 15. The prefabricated hole 16 is communicated with the prefabricated crack 15. The volume of the prefabricated hole 16 is greater than the volume of the prefabricated crack 15. The volume of the prefabricated hole 16 is 5% of the volume of the inner cavity of the air pressure chamber 13.

[0016] In this embodiment, the top of the air pressure chamber 13 is a removable cover plate 18, which is fixedly connected to the air pressure chamber 13 by a plurality of bolts 11, and the bolts 11 are evenly spaced around the cover plate 18. A sealing ring 12 is provided between the cover plate 18 and the air pressure chamber 13.

[0017] Before the test, the four sides of the sheet-like flexible sealing material specimen 14 are fixed to the top surface of the concrete mold 17 by glue, the prefabricated crack 15 is covered by the flexible sealing material specimen 14, and then the air pressure chamber 13 is sealed, and the groove failure test can be started, that is: open the air inlet valve 4, close the air outlet valve 5, adjust the air intake rate of the gas entering the air pressure chamber 13 by the pressure control valve 6, so that the pressure in the air pressure chamber 13 increases linearly, and monitor and record the pressure changes at different time points in the air pressure chamber 13 in real time by the monitoring instrument 9 and the pressure gauge 8, and establish a gas loading curve. When the pressure in the air pressure chamber 13 exceeds the maximum air pressure that the flexible sealing material specimen 14 can withstand, the flexible sealing material specimen 14 will be grooved and destroyed. At this time, the air in the air pressure chamber 13 will flow into the prefabricated hole 16 through the prefabricated crack 15. Due to the sudden increase in space, the pressure in the air pressure chamber 13 will drop suddenly. According to the pressure drop point on the gas loading curve, it is judged at what atmospheric pressure the flexible sealing material specimen 14 is destroyed.

[0018] After the test is finished, the air inlet valve 4 is closed, the air outlet valve 5 is opened, the air pressure chamber 13 is deflated, and then the cover plate 18 is disassembled, and the flexible sealing material test piece 14 and the concrete mold 17 are taken out.

Claims

1. A crack failure test device for flexible sealing materials of compressed air energy storage underground caverns, characterized in that: The invention comprises an air compressor, a booster pump, an air storage tank, an air inlet valve, a pressure control valve, a device body, a pressure gauge and a monitoring instrument which are sequentially connected in a sealed manner through pipelines. An air outlet valve is connected to the pipeline between the air inlet valve and the pressure control valve. The device body comprises a sealable air pressure chamber surrounded by steel plates. A concrete mold is placed at the bottom of the inner cavity of the air pressure chamber. Prefabricated cracks and prefabricated holes are prefabricated in the concrete mold. The prefabricated cracks are arranged at the top of the concrete mold. The length and width of the prefabricated cracks are both smaller than the concrete mold. The prefabricated holes are located directly below the prefabricated cracks. The prefabricated holes are in communication with the prefabricated cracks. The volume of the prefabricated holes is larger than the volume of the prefabricated cracks. Before the test, the four sides of the sheet-like flexible sealing material specimen are fixed to the top surface of the concrete mold by glue, the prefabricated cracks are covered by the flexible sealing material specimen, and then the air pressure chamber is sealed to start the crack failure test, that is, open the air inlet valve, close the air outlet valve, adjust the air intake rate of the gas entering the air pressure chamber by the pressure control valve, so that the pressure in the air pressure chamber increases linearly, and monitor and record the pressure changes in the air pressure chamber at different time points in real time by monitoring instruments and pressure gauges, and establish a gas loading curve. When the pressure in the air pressure chamber exceeds the maximum air pressure that the flexible sealing material specimen can withstand, the flexible sealing material specimen will be cracked and destroyed. At this time, the air in the air pressure chamber will flow into the prefabricated hole through the prefabricated cracks, causing the pressure in the air pressure chamber to drop suddenly. According to the pressure drop point on the gas loading curve, it is judged at what atmospheric pressure the flexible sealing material specimen is destroyed.

2. A crack failure test device for flexible sealing materials of compressed air energy storage underground caverns according to claim 1, characterized in that: The volume of the prefabricated hole is 3-7% of the volume of the inner cavity of the air pressure chamber.

3. A crack failure test device for flexible sealing materials of compressed air energy storage underground caverns according to claim 1, characterized in that: The top of the air pressure chamber is a detachable cover plate, which is fixedly connected to the air pressure chamber by a plurality of bolts. The plurality of bolts are evenly spaced around the cover plate, and a sealing ring is provided between the cover plate and the air pressure chamber.

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