Intensity inspection system and method for cable and protection measure in reactor

Abstract

The invention relates to a strength inspection system and method for cables and protective measures in a reactor. The strength inspection system comprises a jet fluid simulation unit for providing set temperature and pressure fluid and a sample fixing table for fixing the cables and the protective measures, the method comprises the following steps: respectively carrying out jet impact tests in a cable exposed state and a protective measure adding state under a set fluid condition, and determining a critical distance between the cable and a jet nozzle when the cable is damaged under fluid impact in the exposed state and the different protective measure states according to a damage state of the surface of the cable. Under the set fluid condition, the influence conditions of different protection measures on the strength performance of the cable sample piece are tested, so that the critical distance between the cable sample piece and the jet orifice when the surface of the cable sample piece is just not broken is determined, and reference is provided for the installation distance requirement of the cable sample piece.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear energy equipment, and in particular to a strength inspection system and method for cables and protective measures in a reactor. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] The cables in nuclear power reactors are responsible for transmitting control signals and power energy for reactor equipment. For the safe operation of the reactor, it is necessary to ensure that the cables can still maintain normal signal transmission and power transmission functions for a certain period of time when an accident occurs in the reactor. In the event of an accident, the cables are often subjected to the impact of high-temperature and high-pressure fluids. Therefore, strength tests are required to test the ability of the cables to withstand the impact of high-temperature and high-pressure fluids under the influence of different protective measures.

[0004] The existing technology can use a high-pressure pump to generate high-temperature and high-pressure fluid, and use the fluid to perform impact strength tests on the structural parts in the reactor. Although this type of strength test system can be applied to cable strength tests, since the strength of the cable itself has been determined after manufacturing, different installation methods, different protection measures, and different installation positions in the reactor will cause changes in the distance from the high-pressure pipeline to affect the strength performance of the cable, and this effect will be magnified in an accident state. Therefore, the current strength inspection system lacks corresponding test detection means to determine this effect. Summary of the invention

[0005] In order to solve the technical problems existing in the above-mentioned background technology, the present invention provides a strength inspection system and method for cables and protective measures in a reactor, which utilizes a plunger pump to simulate high-temperature and high-pressure fluid under an accident state, and impacts the cable sample through a jet nozzle. By testing the influence of different protective measures on the strength performance of the cable sample under set impact conditions, the critical distance between the cable sample and the jet nozzle when structural damage just occurs is determined, thereby providing a reference for the installation conditions of the cable sample.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A first aspect of the present invention provides a method for testing the strength of cables and protective measures in a reactor, comprising the following steps:

[0008] The cable sample under test is connected between two columns, and the working fluid is pressurized and heated to the set pressure and temperature;

[0009] Under the set fluid pressure, temperature and flow rate, as well as the initial jet spacing, the jet impact test is carried out on the exposed cable sample. After each test, the structural state of the tested cable sample is obtained, and the structural damage state of the tested cable sample is determined by comparing it with the structural state before the test;

[0010] Repeat the test by changing the jet spacing until the cable sample has no structural damage when the set number of consecutive tests is performed under a single set of jet spacing. The jet spacing at this time is the critical spacing at which the cable will be damaged when it is exposed to the fluid impact of the set temperature, pressure and flow rate.

[0011] At the critical spacing, different protective measures are added to the test cable samples of the same type, and jet impact tests are carried out under corresponding fluid pressure, temperature and flow rate; the test is repeated by changing the jet spacing until the test cable samples have no structural damage after the set number of consecutive tests under a single set of jet spacing. The jet spacing at this time is the critical spacing at which the cable will be damaged when it is subjected to fluid impact of set temperature, pressure and flow rate under the corresponding protective measures.

[0012] Furthermore, before the tested cable sample is connected to the column, the initial structural state is obtained by electron microscope scanning.

[0013] Furthermore, after each test, the structural state of the tested cable sample is obtained, and the structural damage state of the tested cable sample is determined by comparing it with the structural state before the test; specifically:

[0014] After each test, the integrity of the tested cable sample is checked by visual observation to determine the surface damage status;

[0015] If there is no damage on the surface, the impacted part is scanned by electron microscope to obtain the structural state after the test. By comparing it with the structural state before the test, it is determined that the tested cable sample has internal tissue damage but no external damage;

[0016] The cable samples under test that are confirmed to have surface damage through naked eye observation and the cable samples under test that are confirmed to have internal damage through electron microscope scanning are both damaged cable samples under test.

[0017] Furthermore, the test was repeated by changing the jet spacing. Specifically, the jet spacing was based on the diameter D of the jet nozzle, 1D was the jet spacing, and the jet impact experiment was repeated each time the 1D spacing was changed.

[0018] Furthermore, the protective measures include a bridge / cable duct connected between two columns and a matching cover plate, the cover plate covers the surface of the bridge / cable duct, and the tested cable sample is protected by the space formed by the bridge / cable duct and the cover plate.

[0019] Furthermore, the protective measures also include a metal hose sleeved on the outer surface of the cable, the test cable sample is sleeved on the metal hose, and end plates are provided on the two columns. The end plates are connected to the end of the metal hose through a joint, so that the test cable sample is protected by the metal hose.

[0020] A second aspect of the present invention provides a strength inspection system for cables and protective measures in a reactor, comprising:

[0021] The jet fluid simulation unit provides a fluid of set temperature and pressure through a plunger pump and a preheating section arranged on a pipeline, and sprays the fluid through a jet nozzle;

[0022] The sample fixing frame has a sample fixing platform for fixing cables and protective measures, the sample fixing platform is provided with at least two groups of columns arranged in parallel, the columns are provided with buckles, the test area of ​​the tested cable sample is arranged between the two groups of columns, and the non-test area is fixed to the columns by buckles.

[0023] Furthermore, the jet fluid simulation unit includes a water tank, a stop valve, a plunger pump and a jet nozzle which are connected in sequence through pipelines. A preheating section is provided in the pipeline between the plunger pump and the jet nozzle. The jet nozzle faces the sample holder. Temperature and pressure detection sensors are provided on the pipeline.

[0024] Furthermore, the sample fixing frame includes a sample fixing table, a triangular support frame and a base. The sample fixing table is movably connected to the triangular support frame and faces the jet nozzle. The triangular support frame is movably connected to the base and is used to adjust the distance between the sample fixing table and the jet nozzle.

[0025] Furthermore, when the outer diameter of the tested cable sample is smaller than the set size, the non-tested areas at both ends are wound around the surface of the column for a set number of turns and then fixed by means of clips; when it is not smaller than the set size, it is fixed to the surface of the column by means of multiple clips.

[0026] Compared with the prior art, one or more of the above technical solutions have the following beneficial effects:

[0027] 1. By changing the conditions of jet impact and the types of protective measures, the critical distance at which the cable samples will be damaged when subjected to fluid impact of different temperatures, pressures and flows in the exposed state and under different protective measures is obtained. The critical distance is used as the installation distance recommendation between the exposed cable and the accident risk point during the reactor design and installation stages to prevent the cable from being damaged by jet impact in a breach accident. The critical distance corresponding to different protective measures can help designers and installers provide a basis for optional protective measures when the cable has to be laid close to the accident risk point (such as a high-pressure pipeline).

[0028] 2. The strength test process takes into account the impact of various conditions on the strength performance of the cable. Through testing, it covers the cable in a bare state and with different protective measures, as well as different jet pressures, temperatures and flow rates. The final jet spacing can reflect the impact of different conditions on the strength performance of the cable, thereby providing a basis for selecting cable protection type and installation location during the reactor design and installation stages.

[0029] 3. With regard to the cable structure, the problem of the cable being separated from the sample fixing table when subjected to fluid impact is taken into consideration. A structure that is wrapped around a column and cooperates with a buckle is used to strengthen the connection strength between the non-test area of ​​the cable and the sample fixing table to avoid separation during the strength test and affect subsequent test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0031] Figure 1 It is a schematic diagram of the structure of a strength inspection system for cables and protective measures in a reactor provided by one or more embodiments of the present invention;

[0032] Figure 2 It is a schematic diagram of the matching structure between the non-test area of ​​the cable and the column provided by one or an embodiment of the present invention;

[0033] Figure 3 is a schematic diagram of a buckle structure provided by one or an embodiment of the present invention;

[0034] Figure 4 It is a schematic diagram of the structure of the sample fixing frame provided by one or an embodiment of the present invention when the bridge is installed;

[0035] Figure 5 It is a schematic structural diagram of a sample fixing frame provided by one or an embodiment of the present invention when a cover plate is installed;

[0036] Figure 6 It is a schematic diagram of the matching structure between a sample cable and a sample fixing frame when a metal hose is installed in a sample cable provided in one or an embodiment of the present invention.

[0037] In the figure: 1 water tank, 2 stop valve, 3 plunger pump, 4 preheating section, 5 jet nozzle, 6 sample fixing table, 7 column, 8 cable, 9 clip, 10 bridge / cable trough, 11 cover plate. DETAILED DESCRIPTION

[0038] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0039] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0040] Terminology explanation:

[0041] Nuclear reactors are key designs that ensure that radioactive materials do not leak into the environment. Generally, nuclear power plants have three safety barriers.

[0042] The first safety barrier is the fuel pellets and fuel cladding. The fuel pellets are usually made of sintered uranium dioxide ceramics. Most of their microporous structures are not connected to the outside world and can retain most of the radioactive materials produced by nuclear fission. The fuel pellets are loaded into cladding made of zirconium alloy or stainless steel to form fuel element rods.

[0043] The second safety barrier is a pressure vessel and a closed primary circuit system. The pressure vessel is used to enclose the core composed of nuclear fuel.

[0044] The third safety barrier is the containment (reactor building), which is generally a prestressed reinforced concrete structure with a thickness of 1 meter and a steel lining on the inner surface, which has good sealing performance. The containment is also equipped with a safety injection system, a containment spray system, a hydrogen removal system, an air purification and cooling system, etc. to cope with possible extreme accidents.

[0045] Various systems within the safety barrier require power supply and transmission of control signals, which means that the cables have corresponding design requirements in terms of electrical continuity, pressure bearing and temperature resistance.

[0046] In addition, as introduced in the background technology, in order to ensure that the cable can maintain normal working capacity for a sufficient time when subjected to the impact of high-temperature and high-pressure fluids under accident conditions, it is necessary to consider the strength limit of the cable under accident conditions during the design stage, and determine a reasonable installation position (for example, a certain distance from possible accident risk points, such as a certain distance from high-pressure pipelines) according to the layout of the equipment in the reactor to alleviate or reduce the impact of the fluid on the cable, so as to extend the working time that the cable can maintain under accident conditions. The existing technology can use a high-pressure pump to generate high-temperature and high-pressure fluids, and use the fluids to perform impact strength tests on structural parts in the reactor.

[0047] When this type of strength test system is applied to the cable strength test, since the strength of the cables in the reactor has been determined after manufacturing, different installation methods, different protection measures and different installation spacing in the reactor will affect the strength performance of the cables, and this impact will be amplified under accident conditions. This type of strength inspection system lacks the corresponding test and detection means to determine this impact.

[0048] Therefore, the following embodiments provide a system and method for testing the strength of cables and protective measures in a reactor. A high-pressure pump is used to simulate high-temperature and high-pressure fluid under an accident state, and the cable sample is impacted through a jet nozzle. By testing the effects of different protective measures on the strength performance of the cable sample under set impact conditions, the critical distance between the cable sample and the jet nozzle when no surface rupture occurs is determined, thereby providing a reference for the installation conditions of the cable sample.

[0049] Embodiment 1:

[0050] When an accident occurs in a reactor, the cables will be subjected to the impact of high-temperature and high-pressure fluids. For example, when a breach occurs in the primary loop pipeline of a pressurized water reactor, water above 15.5MPa and 270°C in the primary loop pipeline will spray out from the breach, forming a high-temperature and high-pressure jet. This part of the fluid will impact the surrounding cables. Therefore, this embodiment tests the tolerance of bridges, cable ducts, and reinforced metal hoses under the impact of high-temperature and high-pressure jets, and provides a reasonable installation method and installation position reference for the actual installation of cables.

[0051] like Figure 1 As shown, the strength inspection system of cables and protective measures in a reactor includes a water storage tank 1, a stop valve 2, a plunger pump 3 and a jet nozzle 5 which are sequentially connected through pipelines. A preheating section 4 is provided in the pipeline between the plunger pump 3 and the jet nozzle 5. The jet nozzle 5 faces the sample fixing frame. Temperature, pressure and flow detection sensors are provided on the pipeline.

[0052] The water tank 1 is used to store the working fluid for testing; the stop valve 2 is used to control the working fluid to flow into the plunger pump 3; the plunger pump 3 is used to pressurize the working fluid to the target pressure; the preheating section 4 is used to heat the working fluid to the target temperature; the sample fixing frame is used to fix the cable sample and its reinforcement measure sample.

[0053] A flow regulating valve is arranged on the pipeline to adjust the flow of the jet nozzle 5 .

[0054] The plunger pump 3 is a high-pressure stage and can accurately control the pressure to ensure that the pressure before the jet nozzle 5 does not fluctuate greatly.

[0055] The preheating section 4 is a multi-stage heating, and is a combination of AC heating and DC heating, and the last stage of heating is DC heating.

[0056] The sample fixing frame comprises a sample fixing platform 6, a triangular support frame and a base. The sample fixing platform is movably connected to the triangular support frame and faces the jet nozzle 5. The base is fixed on the ground, and the triangular support frame is movably connected to the base.

[0057] The sample fixing table 6 is movably connected to the triangular support frame to adjust the horizontal position between the sample fixing table and the jet nozzle 5. The specific structure for adjusting the horizontal position is not limited, and the horizontal position adjustment can be achieved through a slide rail structure.

[0058] The tripod support frame is movably connected to the base to adjust the distance between the sample fixing platform and the jet nozzle 5. The specific structure for achieving the distance adjustment is not limited. For example, the movable connection between the base and the tripod support frame can be achieved by setting corresponding strip holes in the contact area between the base and the tripod support frame. By adjusting the overlap of the strip holes in the base and the tripod support frame, the jet spacing can be adjusted within the length range of the strip holes. After the adjustment is completed, it is locked by fasteners to eliminate the influence of different initial distances from the sample surface to the jet nozzle due to different sizes of the tested cable samples.

[0059] In this embodiment, the sample fixing platform is welded to the triangular support frame, and the welding height is determined by the height of the jet nozzle 5 .

[0060] At least two groups of columns 7 are arranged in parallel on the sample fixing platform 6, and buckles 9 are provided on the columns 7. The cable 8 as the sample is arranged between the two groups of columns 7 in the horizontal direction. The area between the two groups of columns 7 is the test area that receives the impact of the high-temperature and high-pressure fluid ejected from the jet nozzle 5, and the parts fixed on the columns 7 at both ends are the non-test area. In order to ensure that the cable 8 in the test area will not be separated from the sample fixing platform under the impact of the fluid, it is necessary to ensure that the parts of the two ends of the cable 8 in the non-test area can be reliably fixed on the columns 7. In this embodiment, the following is adopted Figure 2 In the structure shown, the cable 8 in the non-test area is wound around the column 7, and the cable 8 is locked on the column 7 by a buckle 9 at the end.

[0061] The structure of the buckle 9 is as follows Figure 3 As shown, it includes a U-shaped locking frame and a fastener passing through the locking frame, the U-shaped opening of the locking frame is connected to the surface of the column 7, the end of the cable 8 is wound around the column 7 for a set number of turns, and then passes through the area between the surface of the column 7 and the U-shaped opening of the locking frame, and through the tightening action of the fastener, the end of the cable 8 is abutted against the surface of the column 7. At the same time, in order to ensure that the surface of the cable 8 is not damaged by the tightening action of the fastener, a flat abutment plate is provided at the end of the fastener.

[0062] The cable 8 in the non-test area is wound in a spiral manner with the column 7. When the cable 8 is subjected to fluid impact, it tends to move away from the jet nozzle 5. The spiral winding method enables the cable 8 to obtain as large a contact area as possible with the surface of the column 7, preventing the cable 8 from detaching from the sample fixing table; at the same time, the spiral winding method can also enable the cable 8 to gradually tighten the column 7, further preventing the cable 8 from detaching from the sample fixing table; in addition, the end of the cable 8 is abutted against the surface of the column 7 through the buckle 9, which can continue to prevent the cable 8 from detaching from the sample fixing table. Through this structure, it can be ensured that the test area of ​​the cable 8 is not easy to detach from the sample fixing table when subjected to fluid impact, thereby obtaining reliable test results.

[0063] When the diameter of the cable 8 exceeds a certain value, it may be difficult to wind it around the column 7 due to its own hardness. In this case, multiple buckles 9 can be used to directly abut and fix the non-test area of ​​the cable 8 on the column 7.

[0064] A bridge / cable duct may also be connected between the two columns 7 , and the bridge / cable duct is used to simulate a bridge / cable duct for accommodating cables 8 in a real reactor.

[0065] A cover plate can also be connected between the two columns 7. The cover plate is used to simulate the components covering the surface of the bridge / cable trough in a real reactor, so that the cable 8 is protected by the space formed by the bridge / cable trough and the cover plate. The cover plate and the bridge / cable trough can offset part of the impact of the high-temperature and high-pressure fluid, so that the bridge / cable trough and the cover plate form a protective measure for the cable 8.

[0066] A metal hose can also be connected between the two columns 7, and the cable 8 is sleeved inside the metal hose. End plates are provided on the two columns 7, and the end plates are connected to the two ends of the metal hose through gland joints, so that the cable 8 is protected by the metal hose. The metal hose can offset part of the impact caused by the high-temperature and high-pressure fluid, so that the metal hose forms a protective measure for the cable 8.

[0067] The strength test system of the above structure is designed for the structure of the sample cable, taking into account the problem that the cable may be detached from the sample fixing table when subjected to fluid impact. It involves a structure that is wrapped around a column and cooperates with a buckle to strengthen the connection strength between the non-test area of ​​the cable and the sample fixing table, thereby avoiding detachment during the strength test and affecting subsequent test results.

[0068] Embodiment 2:

[0069] The strength test method of cables and protective measures in the reactor includes the following steps:

[0070] The cable sample under test is connected between two columns, and the working fluid is pressurized and heated to the set pressure and temperature;

[0071] Under the set fluid pressure, temperature and flow rate, as well as the initial jet spacing, the jet impact test is carried out on the exposed cable sample. After each test, the structural state of the tested cable sample is obtained, and the structural damage state of the tested cable sample is determined by comparing it with the structural state before the test;

[0072] Repeat the test by changing the jet spacing until the cable sample has no structural damage when the set number of consecutive tests is performed under a single set of jet spacing. The jet spacing at this time is the critical spacing at which the cable will be damaged when it is exposed to the fluid impact of the set temperature, pressure and flow rate.

[0073] At the critical spacing, different protective measures are added to the test cable samples of the same type, and jet impact tests are carried out under corresponding fluid pressure, temperature and flow rate; the test is repeated by changing the jet spacing until the test cable samples have no structural damage after the set number of consecutive tests under a single set of jet spacing. The jet spacing at this time is the critical spacing at which the cable will be damaged when it is subjected to fluid impact of set temperature, pressure and flow rate under the corresponding protective measures.

[0074] Connect the bridge / cable duct between two columns 7, such as Figure 4 The test cable sample 8 shown is located in the bridge / cable duct 10 and connected between two columns 7.

[0075] When the cable 8 is fixedly connected, avoid excessive stretching to prevent interference with the test results. For example, the test cable sample cannot be directly straightened on the bridge / cable duct. Instead, a pre-straightened cable is cut according to the spacing between the two columns 7 as a sample and then fixed.

[0076] In this embodiment, for cables with an outer diameter less than 20 mm, the cables are wound around the pillar 7 for multiple turns in the non-test area and then clamped and fixed using the buckles 9. If the cables with an outer diameter not less than 20 mm are difficult to be wound around the pillar 7 due to hardness problems, multiple buckles 9 are directly used to clamp and fix them on the surface of the pillar 7.

[0077] The cable test section after installation is the same as the formal reactor scenario, with a certain degree of freedom, and can move slightly within a certain range to cope with thermal expansion and contraction, and to ensure that there is no position displacement or falling off during the jet impact process.

[0078] After the tested cable 8 is installed, the working fluid is heated and pressurized until it reaches the set pressure and temperature, and jet impact is performed, and the jet pressure, jet temperature and jet flow rate during the test are recorded.

[0079] The jet impact test is carried out under the set pressure, temperature and flow rate. Before the test begins, the impacted part of the tested cable sample is scanned by electron microscope to obtain the state record of its complete structure;

[0080] After each test, firstly, the integrity of the tested cable sample is checked by naked eye observation to determine whether there is any rupture damage on the surface. If there is no obvious rupture damage, the impacted part is scanned by electron microscope to obtain its structural state after the test. By comparing it with the intact structure before the test, the tested cable sample with possible internal tissue damage but no obvious rupture damage on the outside is determined, thereby determining the tested cable sample with damage;

[0081] If the surface of the tested cable sample has rupture damage or the internal tissue damage that may pose a risk to subsequent use is found after electron microscope scanning, the jet spacing is changed. The jet spacing is based on the jet nozzle diameter D. Starting from 1D, the jet impact test is repeated by changing the spacing by 1D each time (i.e. 1D, 2D, 3D until nD);

[0082] In this embodiment, the test is repeated three times for each jet spacing, and the damage on the surface of the tested cable sample is detected after each test until the surface of the tested cable sample is not damaged when the single spacing is tested three times in a row. The jet spacing xD at this time is the critical spacing at which the cable will be damaged when it is subjected to fluid impact of set temperature, pressure and flow in an exposed state. The critical spacing is recommended as the installation spacing between the exposed cable and the accident risk point in the design stage to prevent the cable from being damaged by the jet impact in a breach accident.

[0083] When the cable sample under test is exposed to jet impact at a certain jet distance and has rupture damage on the surface, two enhanced protection measures are added to the cable sample under test of the same type, and then the jet impact test is carried out again at the same distance under the same jet parameters (the pressure, temperature, flow rate and duration during the jet are the same).

[0084] Enhanced protection measures include:

[0085] ① Bridge / cable duct + cover plate: Cover the cover plate 11 on the opening of the bridge / cable duct 10 so that the tested cable sample is protected by the space formed by the bridge / cable duct and the cover plate. The bridge / cable duct 10 and the cover plate 11 are first subjected to the fluid impact. Figure 5 As shown;

[0086] ② Metal hose: Use a metal hose to wrap the test cable sample, and let the metal hose bear the fluid impact first.

[0087] The fixing method of the metal hose is different from the direct fixing of the tested cable sample. A steel plate is used to simulate the end plate of the electrical equipment. The steel plate is connected to the column 7 and a hole is opened. The steel plate and the column can be connected by welding. After the metal hose passes through the hole of the steel plate, the end of the metal hose is connected to the steel plate using a gland joint. The area between the two steel plates is the test area, so that the cable 8 is protected by the metal hose. The metal hose offsets part of the impact of the high-temperature and high-pressure fluid, and disperses the impact force of the jet so that it is not directly impacted by the jet.

[0088] Gland joint is a prior art, which is a device for fixing and protecting wires and cables, usually used at the ends of cables, such as Figure 6 Installation method shown.

[0089] After the test, the cable structure state after the test is observed with the naked eye or scanned with an electron microscope, and compared with the impacted cable sample without protection, to determine the protection ability of different protection measures for the tested cable sample. In this embodiment, each jet spacing is tested three times under different protection measures, and the damage on the surface of the tested cable sample is detected at the end of each test until the surface of the tested cable sample is not damaged when the single spacing is tested three times in a row. The jet spacings yD and zD at this time are respectively the critical spacings for the cable to be damaged when it is subjected to the impact of fluids of set temperature, pressure and flow under the protection measures of bridge / cable trough + cover plate and metal hose. The critical spacing is an optional protection measure provided during the actual design stage and installation stage when the cable has to be laid close to the accident risk point (such as a high-pressure pipeline) to prevent the cable from being damaged by the jet impact in the case of a break accident.

[0090] In practical applications, a number of test specimens can be made from a certain type of cable and divided into three groups of test objects: exposed state group, protection measure group 1: bridge / cable trough + cover plate, and protection measure group 2: metal hose. The above strength tests are carried out separately.

[0091] By changing the conditions of jet impact and the type of protective measures, the ability of the sample cable to withstand fluid impact of different temperatures, pressures and flows in an exposed state and under different protective measures is obtained. The resulting test data can help designers determine the critical distance between the cable and the fluid outlet under different jet impact conditions and protective measures, and then serve as the basis for selecting the cable protection type and installation spacing in the design stage.

[0092] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for testing the strength of cables and protective measures in a reactor, characterized in that: The following steps are involved: The cable sample under test is connected between two columns, and the working fluid is pressurized and heated to the set pressure and temperature; Under the set fluid pressure, temperature and flow rate, as well as the initial jet spacing, the jet impact test is carried out on the exposed cable sample. After each test, the structural state of the tested cable sample is obtained, and the structural damage state of the tested cable sample is determined by comparing it with the structural state before the test; Repeat the test by changing the jet spacing until the cable sample has no structural damage after the set number of consecutive tests under a single set of jet spacing. The jet spacing at this time is the critical spacing at which the cable will be damaged when it is exposed and subjected to the impact of fluids with set temperature, pressure and flow rate. At the critical spacing, different protective measures are added to the test cable samples of the same type, and jet impact tests are carried out under corresponding fluid pressure, temperature and flow rate; the test is repeated by changing the jet spacing until the test cable samples have no structural damage after the set number of consecutive tests under a single set of jet spacing. The jet spacing at this time is the critical spacing at which the cable will be damaged when it is subjected to fluid impact of the set temperature, pressure and flow rate under the influence of the corresponding protective measures.

2. The strength inspection method for cables and protective measures in a reactor according to claim 1, characterized in that: Before the tested cable sample is connected to the column, the initial structural state is obtained by scanning with an electron microscope.

3. The strength inspection method for cables and protective measures in a reactor according to claim 1, characterized in that: After each test, the structural state of the tested cable sample is obtained, and the structural damage state of the tested cable sample is determined by comparing it with the structural state before the test; specifically: After each test, the integrity of the tested cable sample is checked by visual observation to determine the surface damage status; If there is no damage on the surface, the impacted part is scanned by electron microscope to obtain the structural state after the test. By comparing it with the structural state before the test, it is determined that the tested cable sample has internal tissue damage but no external damage; The cable samples under test that are confirmed to have surface damage through naked eye observation and the cable samples under test that are confirmed to have internal damage through electron microscope scanning are both damaged cable samples under test.

4. The strength inspection method for cables and protective measures in a reactor according to claim 1, characterized in that: The test was repeated by changing the jet spacing. Specifically, the jet spacing was based on the diameter D of the jet nozzle, 1D was the jet spacing, and the jet impact experiment was repeated each time the 1D spacing was changed.

5. The strength inspection method for cables and protective measures in a reactor according to claim 1, characterized in that: The protective measures include a bridge / cable duct connected between two columns and a matching cover plate, the cover plate covers the surface of the bridge / cable duct, and the tested cable sample is protected by the space formed by the bridge / cable duct and the cover plate.

6. The strength inspection method for cables and protective measures in a reactor according to claim 1, characterized in that: The protective measures also include a metal hose sleeved on the outer surface of the cable. The cable sample under test is sleeved on the metal hose. End plates are provided on both columns. The end plates are connected to the ends of the metal hose through joints, so that the cable sample under test is protected by the metal hose.

7. A strength inspection system for cables and protective measures in a reactor implementing the method according to any one of claims 1 to 6, characterized in that: include: The jet fluid simulation unit provides a fluid of set temperature and pressure through a plunger pump and a preheating section arranged on a pipeline, and sprays the fluid through a jet nozzle; The sample fixing frame has a sample fixing platform for fixing the tested cable sample and protective measures, the sample fixing platform is provided with at least two groups of columns arranged in parallel, the columns are provided with buckles, the tested area of ​​the tested cable sample is arranged between the two groups of columns, and the non-tested area is fixed to the columns by buckles.

8. The strength inspection system for cables and protective measures in a reactor as claimed in claim 7, characterized in that: The jet fluid simulation unit comprises a water storage tank, a stop valve, a plunger pump and a jet nozzle which are sequentially connected by pipelines. A preheating section is arranged in the pipeline between the plunger pump and the jet nozzle. The jet nozzle faces the sample fixing frame. Temperature and pressure detection sensors are arranged on the pipeline.

9. The strength inspection system for cables and protective measures in a reactor according to claim 7, characterized in that: The sample fixing frame comprises a sample fixing platform, a triangular support frame and a base. The sample fixing platform is movably connected to the triangular support frame and faces the jet nozzle. The triangular support frame is movably connected to the base and is used to adjust the distance between the sample fixing platform and the jet nozzle.

10. The strength inspection system for cables and protective measures in a reactor according to claim 7, characterized in that: When the outer diameter of the tested cable sample is smaller than the set size, the non-tested areas at both ends are wound around the surface of the column for a set number of turns and then fixed with clips; when it is not smaller than the set size, it is fixed to the surface of the column with multiple clips.

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