A temperature measuring device and reactor coolant system

Abstract

The present invention provides a temperature measuring device and a reactor coolant system, which are applied to a reactor coolant system including a main pipeline, wherein the temperature measuring device includes: a confluence pipeline, which is arranged inside the main pipeline, wherein the first end of the confluence pipeline is a closed end, and the second end of the confluence pipeline is an open end; at least two drainage pipes, wherein the first end of the drainage pipe is connected to the first end of the confluence pipeline, and the second end of the drainage pipe is connected to the pipe wall of the main pipeline, and the drainage pipe is provided with at least two sampling holes; and at least two temperature sensors, wherein the sensing end of the temperature sensor is arranged in the confluence pipeline. In this way, the temperature of the reactor coolant in the confluence pipeline can be directly measured without adding a temperature measurement bypass to the main pipeline, thereby avoiding the risk of leakage and rupture that may be caused by the temperature measurement bypass, thereby improving the safety of the nuclear power plant.

Description

Technical Field

[0001] The invention relates to the field of nuclear power technology, and in particular to a temperature measuring device and a reactor coolant system. Background Art

[0002] The average temperature of the reactor coolant is an important indicator for power control and reactivity control in a pressurized water reactor nuclear power plant, and it is particularly important to measure the average temperature of the reactor coolant in the main pipeline. At present, an independent temperature measurement bypass is usually connected to the main pipeline, and the coolant in the main pipeline is introduced into the bypass, and then the temperature of the coolant introduced into the bypass is measured by a temperature sensor to obtain the average temperature of the reactor coolant in the main pipeline. However, since the above method is provided with a temperature measurement bypass, the temperature measurement bypass is the boundary of the reactor coolant system, and there is a possibility of leakage and breach, which leads to a lower safety of the nuclear power plant. Summary of the invention

[0003] The purpose of the embodiments of the present invention is to provide a temperature measurement device and a reactor coolant system, which solves the problem of low safety of nuclear power plants due to the possibility of leakage and rupture in the temperature measurement bypass.

[0004] To achieve the above object, an embodiment of the present invention provides a temperature measuring device, which is applied to a reactor coolant system including a main pipeline, and the temperature measuring device includes:

[0005] A confluence pipeline is arranged inside the main pipeline, the first end of the confluence pipeline is a closed end, and the second end of the confluence pipeline is an open end;

[0006] at least two drainage tubes, wherein a first end of each drainage tube is connected to a first end of each confluence pipeline, a second end of each drainage tube is connected to a pipe wall of each main pipe, and at least two sampling holes are provided on each drainage tube; and

[0007] At least two temperature sensors, wherein the sensing ends of the temperature sensors are arranged in the confluence pipeline.

[0008] Optionally, each drainage tube is located at different positions on the same cross section of the main pipeline.

[0009] Optionally, the intervals between the second ends of every two adjacent drainage tubes are the same; and / or

[0010] The first end of the confluence pipeline is arranged on the central axis of the main pipeline.

[0011] Optionally, the position of the first end of the conduit is higher than the position of the second end of the conduit.

[0012] Optionally, a liquid outlet pipeline is provided at the second end of the confluence pipeline, the pipe wall of the liquid outlet pipeline is in close contact with the bottom pipe wall of the main pipeline, and the sensing end of the temperature sensor is located in the liquid outlet pipeline.

[0013] Optionally, the temperature sensor includes:

[0014] a fixed portion; and

[0015] The measuring part is provided with a first end and a second end opposite to each other, the first end of the measuring part is provided on the fixing part, the second end of the measuring part passes through the bottom pipe wall of the main pipeline and the pipe wall of the liquid outlet pipeline, and extends into the liquid outlet pipeline, and the second end of the measuring part is the sensing end of the temperature sensor.

[0016] Optionally, an opening is provided at a position on the main pipeline that is in close contact with the wall of the liquid outlet pipeline;

[0017] A fixing reinforcement member is disposed in the opening, the fixing reinforcement member is provided with a first surface and a second surface opposite to each other, and is provided with a plurality of accommodating cavities having the same number as the temperature sensors, wherein:

[0018] The first surface is in close contact with the tube wall of the liquid outlet pipeline, the second surface is exposed outside the bottom tube wall of the main pipeline, the at least two temperature sensors are respectively arranged in the multiple accommodating cavities, and the second end of the measuring part passes through the first surface and the tube wall of the liquid outlet pipeline and extends into the liquid outlet pipeline.

[0019] Optionally, the fixing portion is provided with a first end and a second end opposite to each other, and the first end of the measuring portion is located on the first end of the fixing portion;

[0020] The fixing reinforcement member further comprises:

[0021] A sealing gasket, arranged at the connection between the fixing part and the measuring part;

[0022] a spring disposed at the second end of the fixing portion; and

[0023] The sealing bolt is arranged at one end of the spring away from the fixing portion.

[0024] Optionally, the number of the drainage tubes and the number of the temperature sensors are both greater than or equal to three, and the number of the sampling holes is greater than or equal to five.

[0025] An embodiment of the present invention further provides a reactor coolant system, comprising the temperature measuring device provided by the embodiment of the present invention.

[0026] In the embodiment of the present invention, the temperature of the reactor coolant in the confluence pipe can be directly measured by the sensing end of the temperature sensor arranged in the confluence pipe, without adding a temperature measurement bypass to the main pipe, thereby avoiding the risk of leakage and rupture that may be caused by the temperature measurement bypass, thereby improving the safety of the nuclear power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the structure of a temperature measurement device provided by an embodiment of the present invention;

[0028] Figure 2 A longitudinal section of a temperature measurement device provided by an embodiment of the present invention;

[0029] Figure 3 A cross-sectional view of a temperature measurement device provided by an embodiment of the present invention;

[0030] Figure 4 A schematic structural diagram of a fixing reinforcement member provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0032] like Figures 1 to 4 As shown, an embodiment of the present invention provides a temperature measuring device 1, which is applied to a reactor coolant system including a main pipeline 2. The temperature measuring device 1 includes:

[0033] The confluence pipe 11 is arranged inside the main pipe 2, the first end 111 of the confluence pipe is a closed end, and the second end 112 of the confluence pipe is an open end;

[0034] at least two drainage tubes 12, wherein the first end of the drainage tube 12 is connected to the first end 111 of the confluence pipeline, the second end of the drainage tube 12 is connected to the pipe wall of the main pipe 2, and the drainage tube 12 is provided with at least two sampling holes 120; and

[0035] At least two temperature sensors 13 , wherein the sensing ends 130 of the temperature sensors 13 are disposed in the conduit 11 .

[0036] In an embodiment of the present invention, the reactor coolant system may be a reactor coolant system in a pressurized water reactor nuclear power plant; the main pipeline 2 may also be referred to as a reactor coolant pipeline, and its function is to transport the reactor coolant under the drive of the main pump. The main pipeline 2 may include a hot pipe section, a cold pipe section, and a transition pipe section between the steam generator and the main pump, etc., and there is no limitation to this. When the reactor coolant system is in operation, the reactor coolant will circulate in the reactor coolant system driven by the main pump, that is, the reactor coolant in the main pipeline 2 can always flow and be transported in one direction, for example, it may be Figure 2 The direction indicated by the black arrow on the far left. Here, the sampling hole 120 can face the direction opposite to the flow direction of the reactor coolant, that is, the sampling hole 120 faces the upstream direction. The pressure of the reactor coolant at the sampling hole 120 is greater than the pressure in the drainage tube 12, thereby generating a pressure difference. Driven by the pressure difference, it can ensure that the reactor coolant flows smoothly into the drainage tube 12 and merges into the confluence pipeline 11, and finally flows out from the second end 112 of the confluence pipeline. Of course, the sampling hole 120 can also be set at other positions, and the position of the sampling hole 120 is not limited, so that the reactor coolant can flow from the drainage tube 12 to the confluence pipeline 11 and flow out from the confluence pipeline 11. In addition, the arrangement distance of the sampling holes, that is, the distance between adjacent sampling holes 120, can be evenly arranged in the radial direction of the main pipeline 2 to ensure that representative temperature samples can be collected from the central axis of the main pipeline 2 to the pipe wall, and there is no limitation on this. For example, the sampling holes 120 of the drainage tube 12 close to the central axis of the main pipeline 12 may be arranged sparsely, while the sampling holes 120 close to the pipe wall of the main pipeline may be arranged more densely.

[0037] The function of the drainage pipe 12 may be to introduce the reactor coolant into the drainage pipe 12, and to make the reactor coolant flow out of the drainage pipe 12 to the converging pipe 11. The function of the converging pipe 11 is to collect and mix the reactor coolants from the at least two drainage pipes 12, so that the flow in the converging pipe 11 becomes more uniform, so that the temperature sensor 13 measures the average temperature of the same mixed flow, thereby improving the accuracy of the measurement result.

[0038] The temperature sensor 13 is mainly used to measure the temperature of the flow in the confluence pipe 11; it can be set on the main pipe, or it can also be set on the confluence pipe 11, and there is no restriction on this, so that the sensing end 130 of the temperature sensor 13 can be set in the confluence pipe 11, that is, the temperature sensor 13 can only measure the temperature of the flow in the confluence pipe 11, but not the temperature of other flows on the main pipe. It should be noted that the flow rate of the reactor coolant in the confluence pipe 11 is relatively gentle, and the sensing end 130 of the temperature sensor 13 is less impacted, so that the sensing end 130 is in direct contact with the reactor coolant, which can ensure the sensitivity of the temperature measurement and thus improve the accuracy of the measurement result. Preferably, the temperature sensor 13 can be an armored temperature sensor; this can make the temperature sensor 13 have good mechanical properties, vibration resistance and impact resistance; and the sensing end 130 has a fast response speed.

[0039] In addition, the first end of the drainage pipe 12 is connected to the first end 111 of the confluence pipe, which may mean that the end face of the first end 111 of the confluence pipe is closed, and a through hole is provided on the side of the first end 111 of the confluence pipe, and the first end of the drainage pipe 12 is connected to the side of the first end 111 of the confluence pipe through the through hole, so that the reactor coolant can flow from the drainage pipe 12 into the first end 111 of the confluence pipe.

[0040] To make the scheme of this embodiment clearer, the working principle of the temperature measuring device 1 is described below: when the reactor coolant system is operating normally, the reactor coolant in the main pipeline 2 flows at a high speed driven by the main pump, flushing the at least two drainage pipes 12, which will generate a higher pressure head in the flow section; driven by the pressure head, part of the coolant enters the drainage pipe 12 through the sampling hole 120, and flows along the internal channel to the confluence pipe 11; thereafter, the reactor coolant flowing out of each drainage pipe 12 will be collected and mixed in the confluence pipe 11, and flow from the first end 111 of the confluence pipe to the second end 112 of the confluence pipe, and finally flow out from the second end 112 of the confluence pipe into the main pipeline 2 after flushing the sensing end 130 of the temperature sensor 13 arranged in the confluence pipe 11. Among them, when the sensing end 130 of the temperature sensor 13 is flushed by the reactor coolant, it can sense the temperature of the reactor coolant, and after converting the temperature into an electrical signal, transmit it to the acquisition and control system.

[0041] In this way, the embodiment of the present invention can directly measure the temperature of the reactor coolant in the busbar pipe 11 by means of the sensing end 130 of the temperature sensor 13 arranged in the busbar pipe 11, without adding a temperature measurement bypass to the main pipeline 2, thereby avoiding the risk of leakage and rupture that may be caused by the temperature measurement bypass, thereby improving the safety of the nuclear power plant.

[0042] Optionally, each drainage pipe 12 is located at different positions on the same cross section of the main pipeline 2 .

[0043] In this embodiment, by setting each drainage tube 12 at the same cross section of the main pipeline 2, the flow rate of each drainage tube 12 entering the converging pipeline 11 can be the flow rate of the same cross section, which can make the measurement result more accurate. Of course, each drainage tube 12 can also be set at other positions, for example, each drainage tube 12 can also be located at multiple different cross sections; there is no limitation on this.

[0044] In this way, the temperature value measured by the temperature sensor 13 can be made more representative, further reducing the uncertainty of the temperature measurement and increasing its reliability.

[0045] Optionally, the intervals between the second ends of every two adjacent drainage tubes 12 are the same; and / or

[0046] The first end 111 of the confluence pipe is disposed on the central axis of the main pipe 2 .

[0047] In this embodiment, when the interval between the second ends of each two adjacent drainage tubes 12 is the same, or the first end 111 of the confluence pipeline is arranged on the central axis of the main pipeline 2, or both situations exist, the accuracy of temperature measurement can be effectively improved. Of course, the interval between the second ends of each two adjacent drainage tubes 12 can also be different, and the first end 111 of the confluence pipeline can also be arranged at other positions, which are not limited.

[0048] Optionally, the position of the first end 111 of the conduit is higher than the position of the second end 112 of the conduit. In this embodiment, there is a height difference between the position of the first end 111 of the conduit and the position of the second end 112 of the conduit, and the height difference can generate a pressure difference that drives the reactor coolant to flow from the first end 111 of the conduit to the second end 112 of the conduit; the pressure difference can accelerate the flow of the reactor coolant in the conduit 11, thereby improving the efficiency of temperature measurement. Of course, the position of the first end 111 of the conduit and the position of the second end 112 of the conduit can also be set at other places; for example, the first end 111 of the conduit and the second end 112 of the conduit can be both located on the same straight line, or the position of the first end 111 of the conduit can also be lower than the position of the second end 112 of the conduit, etc.; there is no limitation to this.

[0049] Optionally, a liquid outlet pipeline 110 is provided at the second end 112 of the confluence pipeline, the wall of the liquid outlet pipeline 110 is in close contact with the bottom wall of the main pipeline 2 , and the sensing end 130 of the temperature sensor 13 is located in the liquid outlet pipeline 110 .

[0050] In this embodiment, the wall of the liquid outlet pipeline 110 is in close contact with the bottom wall of the main pipeline 2, and the bottom wall of the main pipeline 2 can provide support for the liquid outlet pipeline 110, that is, in addition to the support point of the first end 111 of the confluence pipeline, an additional support point is provided, so that the confluence pipeline 11 is more reliably fixed in the main pipeline 2. The sensing end 130 of the temperature sensor 13 is located in the liquid outlet pipeline 110, so that the temperature measured by the temperature sensor 13 can be the relatively uniform reactor coolant temperature after being fully mixed in the confluence pipeline 11, so that the measurement result can be more accurate.

[0051] Optionally, the temperature sensor 13 includes:

[0052] The fixing portion 131 may be disposed on the bottom wall of the main pipeline 2; and

[0053] The measuring part 132 is provided with a first end and a second end opposite to each other. The first end of the measuring part 132 is provided on the fixing part 131, and the second end of the measuring part 132 passes through the bottom pipe wall of the main pipe 2 and the pipe wall of the liquid outlet pipe 110, and extends into the liquid outlet pipe 110. The second end of the measuring part 132 is the sensing end 130 of the temperature sensor 13.

[0054] In this embodiment, by only setting the sensing end 130 of the temperature sensor 13 in the liquid outlet pipeline 110, that is, only the sensing end 130 is in contact with the reactor coolant, the temperature sensor can be less likely to be corroded by the liquid, thereby increasing the service life. It can be understood that in this embodiment, the temperature sensor can be installed outside the main pipeline 12, for example, by flange connection or threaded connection. This will reduce the difficulty of installation and removal of the temperature sensor 13, thereby facilitating the replacement and maintenance of the temperature sensor 13.

[0055] Optionally, an opening 20 is provided at a position on the main pipeline 2 that is in close contact with the wall of the liquid outlet pipeline 110;

[0056] A fixing reinforcement member 3 is disposed in the opening 20, and the fixing reinforcement member 3 is provided with a first surface and a second surface opposite to each other, and is provided with a plurality of accommodating cavities 30 having the same number as the temperature sensors 13, wherein:

[0057] The first surface is in close contact with the tube wall of the liquid outlet pipeline 110, and the second surface is exposed outside the bottom tube wall of the main pipeline 2. The at least two temperature sensors 13 are respectively arranged in the multiple accommodating cavities 30, and the second end of the measuring part 132 passes through the first surface and the tube wall of the liquid outlet pipeline 110, and extends into the liquid outlet pipeline 110.

[0058] In this embodiment, it is easy to know that the thickness of the fixing reinforcement member 3 is thicker than the thickness of the pipe wall of the converging pipe 11, so that the thin pipe wall of the converging pipe 11 can be strengthened, and the temperature sensor 13 disposed therein can also be protected. In addition, the at least two temperature sensors 13 are respectively disposed in the plurality of accommodating cavities 30, which may mean that each temperature sensor 13 is disposed in each accommodating cavity 30 in a one-to-one correspondence, that is, each accommodating cavity 30 is provided with a temperature sensor 13; in this way, the arrangement of the temperature sensor 13 can be more facilitated by the accommodating cavity 30.

[0059] It should be noted that the shape of the opening 20 may match the shape of the fixing reinforcement member 3 , and the fixing reinforcement member 3 may be welded to the opening 20 to fill the opening 20 .

[0060] Optionally, the fixing portion 131 is provided with a first end and a second end opposite to each other, and the first end of the measuring portion 132 is located on the first end of the fixing portion 131;

[0061] The fixing reinforcement member 3 also includes:

[0062] A sealing gasket 31 is provided at the connection between the fixing portion 131 and the measuring portion 132;

[0063] A spring 32, disposed at the second end of the fixing portion 131; and

[0064] The sealing bolt 33 is disposed at one end of the spring 32 away from the fixing portion 131 .

[0065] In this embodiment, the accommodating cavity 30 may be a through hole having a structure matching the shape of the temperature sensor, and the through hole may be divided into two parts, one part being a channel for the measuring part 131 of the temperature sensor to pass through, and the other part being a cavity for accommodating the fixing part 132. The sealing bolt 33 may compress the spring 32, so that the sealing gasket 31 and the fixing part 131 are pressed against the accommodating cavity 30, specifically, may be pressed against the connection between the above-mentioned channel and the cavity, thereby forming a seal and fixing the temperature sensor 132 with the accommodating cavity 30. In this way, the leakage of the reactor coolant can be prevented, so that the reactor coolant system can operate safely under relatively harsh working conditions.

[0066] Optionally, the number of the drainage tubes 12 and the number of the temperature sensors 13 are both greater than or equal to three, and the number of the sampling holes 120 is greater than or equal to five.

[0067] In this embodiment, when the number of the temperature sensors 13 is greater than or equal to three, the failure of the temperature sensor 13 can be identified by comparing the temperature values ​​measured by each temperature sensor 13. For example, if three temperature values ​​A, B and C are measured, A and B are the same, and C is a different temperature value, it can be explained that the temperature sensor 13 corresponding to C may be faulty and needs to be replaced or maintained.

[0068] It should be noted that the number of the drainage tubes 12 and the temperature sensors 13 can be the same or different, and there is no correlation between the two. For example, when the number of the drainage tubes 12 is three, the number of the temperature sensors 13 can be three or four. In addition, the number of the sampling holes 120 is greater than or equal to five, which can make the introduction speed of the reactor coolant introduced into the drainage tube 12 faster and more uniform.

[0069] In summary, this implementation can make the temperature measurement result more accurate and reliable.

[0070] An embodiment of the present invention further provides a reactor coolant system, comprising the temperature measuring device provided by the embodiment of the present invention.

[0071] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A temperature measuring device, characterized in that: Applied to a reactor coolant system including a main pipeline, the temperature measuring device comprises: A confluence pipeline is arranged inside the main pipeline, the first end of the confluence pipeline is a closed end, and the second end of the confluence pipeline is an open end; at least two drainage tubes, wherein a first end of each drainage tube is connected to a first end of each confluence pipeline, a second end of each drainage tube is connected to a pipe wall of each main pipe, and at least two sampling holes are provided on each drainage tube; and At least two temperature sensors, the sensing ends of the temperature sensors are arranged in the confluence pipe, the first end of the drainage pipe is connected to the first end of the confluence pipe, the end face of the first end of the confluence pipe is closed, the side of the first end of the confluence pipe is provided with a through hole, and the first end of the drainage pipe is connected to the side of the first end of the confluence pipe through the through hole.

2. The temperature measuring device according to claim 1, characterized in that: The drainage pipes are respectively located at different positions on the same cross section of the main pipeline.

3. The temperature measuring device according to claim 2, characterized in that: The intervals between the second ends of every two adjacent drainage tubes are the same; and / or The first end of the confluence pipeline is arranged on the central axis of the main pipeline.

4. The temperature measuring device according to claim 2, characterized in that: The position of the first end of the conduit is higher than the position of the second end of the conduit.

5. The temperature measuring device according to claim 4, characterized in that: A liquid outlet pipeline is arranged at the second end of the confluence pipeline, the pipe wall of the liquid outlet pipeline is in close contact with the bottom pipe wall of the main pipeline, and the sensing end of the temperature sensor is located in the liquid outlet pipeline.

6. The temperature measuring device according to claim 5, characterized in that: The temperature sensor comprises: a fixed portion; and The measuring part is provided with a first end and a second end opposite to each other, the first end of the measuring part is provided on the fixing part, the second end of the measuring part passes through the bottom pipe wall of the main pipeline and the pipe wall of the liquid outlet pipeline, and extends into the liquid outlet pipeline, and the second end of the measuring part is the sensing end of the temperature sensor.

7. The temperature measuring device according to claim 6, characterized in that: An opening is provided on the main pipeline at a position in close contact with the wall of the liquid outlet pipeline; A fixing reinforcement member is disposed in the opening, the fixing reinforcement member is provided with a first surface and a second surface opposite to each other, and is provided with a plurality of accommodating cavities having the same number as the temperature sensors, wherein: The first surface is in close contact with the tube wall of the liquid outlet pipeline, the second surface is exposed outside the bottom tube wall of the main pipeline, the at least two temperature sensors are respectively arranged in the multiple accommodating cavities, and the second end of the measuring part passes through the first surface and the tube wall of the liquid outlet pipeline and extends into the liquid outlet pipeline.

8. The temperature measuring device according to claim 7, characterized in that: The fixing portion is provided with a first end and a second end opposite to each other, and the first end of the measuring portion is located on the first end of the fixing portion; The fixing reinforcement member further comprises: A sealing gasket, arranged at the connection between the fixing part and the measuring part; a spring disposed at the second end of the fixing portion; and The sealing bolt is arranged at one end of the spring away from the fixing portion.

9. The temperature measuring device according to any one of claims 1 to 8, characterized in that: The number of the drainage tubes and the number of the temperature sensors are both greater than or equal to three, and the number of the sampling holes is greater than or equal to five.

10. A reactor coolant system, characterized in that: The device comprises a temperature measuring device as claimed in any one of claims 1 to 9.

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