Upper reactor internals and supercritical water cooled reactor

Abstract

The invention provides an upper reactor internals and supercritical water cooled reactor, the upper reactor internals comprise a compaction cylinder and an isolation cylinder, the top of the compaction cylinder is provided with a support plate, the compaction cylinder is internally provided with an accommodating space, the compaction cylinder is also internally provided with an isolation plate, the isolation plate divides the accommodating space into a first accommodating cavity and a second accommodating cavity along the axial direction of the compaction cylinder, and the first accommodating cavity and the second accommodating cavity are communicated with each other. The first accommodating cavity is communicated with the outlet connecting pipe, and the second accommodating cavity is communicated with the inlet connecting pipe; the isolation cylinder penetrates through the containing space in the axial direction of the pressing cylinder, one end of the isolation cylinder is connected with the isolation plate, and the second containing cavity comprises an inlet cold cavity formed by the outer side of the isolation cylinder and the pressing cylinder in a matched mode and an outlet hot cavity in the isolation cylinder; at least two guide cylinder assemblies are arranged in the radial direction of the pressing cylinder, at least one of the at least two guide cylinder assemblies is arranged in the isolation cylinder in a penetrating mode, and the other guide cylinder assemblies are arranged outside the isolation cylinder in a penetrating mode. According to the upper reactor internals, a low-temperature coolant entering the pressure vessel can be separated from a high-temperature coolant flowing out of the pressure vessel, and the separation requirement of a double-flow channel is met.

Description

Technical Field

[0001] The invention relates to the technical field of supercritical water-cooled reactors, and in particular to an upper reactor internal component and a supercritical water-cooled reactor. Background Art

[0002] The supercritical water-cooled reactor is the only water-cooled reactor among the six reactor types identified by the International Forum on the Fourth Generation of Nuclear Energy Systems. At present, research on reactor structures with single-flow, dual-flow, and triple-flow coolants has been carried out. For the three-flow design, the design, manufacture, installation, commissioning, and overhaul and maintenance of the reactor internals are relatively difficult, while for the single-flow design, the axial non-uniformity of the core is relatively large, so the dual-flow design is adopted.

[0003] In the dual-flow design, the coolant needs to pass through the core area twice, and its temperature gradually increases with the flow until it becomes supercritical. Due to safety requirements, the inlet and outlet pipes on the reactor pressure vessel are generally located above the core, and both cold and hot fluids enter and exit the reactor pressure vessel in the chamber above the core. Therefore, the upper internal components in the supercritical water-cooled reactor need to focus on the function of separating the cold and hot fluid flow channels. Secondly, there is a temperature difference of about 200°C between the coolant at the inlet and outlet, and the cooling fluid also needs to be insulated to avoid large heat losses through the flow channel isolation device, which reduces thermal efficiency.

[0004] Based on this, the inventor of the present application proposes an upper reactor internal component and a supercritical water-cooled reactor in order to solve the above technical problems. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the defect that the upper reactor internals in the prior art do not meet the dual-flow requirements, and to provide an upper reactor internals and a supercritical water-cooled reactor.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] The present invention provides an upper internal component, which is characterized by comprising:

[0008] A compression cylinder, with a support plate on the top, a containing space inside the compression cylinder, and a separation plate in the compression cylinder, the separation plate divides the containing space into a first containing chamber and a second containing chamber along the axial direction of the compression cylinder, the first containing chamber is connected to the outlet pipe, and the second containing chamber is connected to the inlet pipe;

[0009] An isolation cylinder is axially arranged in the accommodating space along the compression cylinder and one end of the isolation cylinder is connected to the isolation plate. The second accommodating chamber includes an inlet cold chamber formed by the outer side of the isolation cylinder and the compression cylinder, and an outlet hot chamber inside the isolation cylinder; wherein,

[0010] At least two guide cylinder assemblies are radially arranged on the compression cylinder, at least one of the at least two guide cylinder assemblies is inserted into the isolation cylinder, and the remaining guide cylinder assemblies are inserted outside the isolation cylinder.

[0011] According to one embodiment of the present invention, at least one flow hole is formed on the compression cylinder, and the flow hole is connected with the second accommodating chamber and the inlet pipe;

[0012] The compression cylinder is also provided with at least one discharge hole, which is communicated with the outlet pipe and the first accommodating chamber respectively.

[0013] According to one embodiment of the present invention, the isolation plate is provided with at least one water flow hole on the inner side of the isolation cylinder, and the water flow hole is communicated with the first accommodating cavity and the outlet heat chamber.

[0014] According to one embodiment of the present invention, a core upper plate is further provided at the bottom of the compression cylinder, and the second accommodating cavity is between the core upper plate and the isolation plate;

[0015] The guide tube assembly is provided with at least one conducting hole on the upper portion of the core upper plate, and the conducting hole is used for introducing or discharging the coolant in the guide tube assembly.

[0016] According to one embodiment of the present invention, the guide cylinder assembly includes at least one first guide cylinder assembly and at least one second guide cylinder assembly;

[0017] The first guide tube assembly is located outside the isolation tube, and one end of the first guide tube assembly is connected to the support plate, and the other end is connected to the core upper plate and communicated with the first fuel assembly to guide a process coolant from the inlet pipe to the lower chamber;

[0018] The second guide tube assembly is located inside the isolation tube, and one end is connected to the support plate, and the other end is connected to the core upper plate and communicated with the second fuel assembly to guide the second process coolant from the lower chamber to the outlet hot chamber.

[0019] According to one embodiment of the present invention, the core upper plate is sealed and connected to the clamping cylinder.

[0020] According to one embodiment of the present invention, a first heat insulation coating is provided on the outer peripheral wall of the isolation cylinder;

[0021] The isolation plate is located on the lower surface of the isolation cylinder and is provided with a second heat insulation coating.

[0022] According to one embodiment of the present invention, the thermal insulation coating is a thermal barrier coating.

[0023] According to one embodiment of the present invention, the isolation panel comprises a mounting outer panel and a matching inner panel;

[0024] A matching groove is provided in the middle of the installation outer plate, and one end cover of the matching inner plate is arranged in the matching groove and installed above the installation outer plate.

[0025] According to one embodiment of the present invention, the mating inner plate is connected to the mounting outer plate by at least one threaded connection;

[0026] The matching inner plate is provided with a light hole matched with the threaded connector, and the threaded connector forms a buffer gap with the mounting inner plate in the light hole.

[0027] The present invention also provides a supercritical water-cooled reactor, which is characterized in that it comprises: a pressure vessel and the upper internals as described above, wherein the upper internals are installed in the pressure vessel.

[0028] The positive and progressive effects of the present invention are:

[0029] The upper in-core components, the compression tube and the isolation tube of the present invention can cooperate to separate the coolant with a lower temperature entering the pressure vessel from the coolant with a higher temperature flowing out of the pressure vessel after being heated by the core, thereby meeting the flow channel separation requirements of the dual-flow design. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0031] Figure 1 It is a schematic diagram of the internal structure of the upper pile internal component of the present invention;

[0032] Figure 2 It is a top view of the isolation plate in the figure;

[0033] Figure 3 for Figure 1 Schematic diagram of the structure of the middle isolation cylinder;

[0034] Figure 4 A schematic structural diagram of another embodiment of an isolation plate;

[0035] Figure 5 for Figure 4 A partial schematic diagram of the installation of the outer panel and the matching inner panel;

[0036] Figure 6 for Figure 4 Schematic diagram of the structure of the outer panel installed in the middle;

[0037] Figure 7 It is a structural schematic diagram of another embodiment of the first guide cylinder assembly.

[0038] 1. Compressing cylinder; 11. Support plate; 12. Accommodating space; 13. Isolation plate; 131. Water flow hole; 132. Second thermal insulation coating; 133. Install outer plate; 134. Matching inner plate; 135. Matching groove; 136. Threaded connector; 137. Buffer gap; 14. First accommodating cavity; 15. Second accommodating cavity; 16. Flow hole; 17. Discharge hole; 18. Core upper plate; 19. First thermal insulation coating;

[0039] 2. Isolation tube; 21. Inlet cold chamber; 22. Outlet hot chamber;

[0040] 3. Guide cylinder assembly; 31. Conducting hole; 32. First guide cylinder assembly; 33. Second guide cylinder assembly. DETAILED DESCRIPTION

[0041] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0043] Please refer to Figures 1 to 7 The present invention proposes an upper in-core component, which includes a compression tube 1 and an isolation tube 2. A support plate 11 is provided on the top of the compression tube 1. The compression tube 1 has a accommodating space 12. An isolation plate 13 is also provided in the compression tube 1. The isolation plate 13 divides the accommodating space 12 into a first accommodating chamber 14 and a second accommodating chamber 15 along the axial direction of the compression tube 1. The first accommodating chamber 14 is connected to the outlet pipe, and the second accommodating chamber 15 is connected to the inlet pipe, wherein the inlet pipe and the outlet pipe are arranged on the pressure vessel, and the inlet pipe is used to introduce a coolant with a relatively low temperature into the core, and the coolant with a high temperature after the core is heated is discharged to the outside of the core through the outlet pipe.

[0044] The isolation cylinder 2 is axially arranged in the accommodating space 12 along the compression cylinder 1 and one end is connected to the isolation plate 13. The second accommodating chamber 15 includes an inlet cold chamber 21 formed by the outer side of the isolation cylinder 2 and the compression cylinder 1, and an outlet hot chamber 22 inside the isolation cylinder 2; wherein, the compression cylinder 1 is radially provided with at least two guide cylinder assemblies 3, at least one of the at least two guide cylinder assemblies 3 is arranged in the isolation cylinder 2, and the remaining guide cylinder assemblies 3 are arranged outside the isolation cylinder 2.

[0045] A mounting flange is provided on the top of the compression cylinder 1. The mounting flange is used to bear the weight of the upper internal components when placed. The flange is integrally provided with the compression cylinder 1 and is connected to the top cover of the pressure vessel on the circumference. The connection method can be welding or other methods, which are not limited here. The support plate 11 is used to isolate the top cover of the pressure vessel and the accommodating space 12.

[0046] The isolation plate 13 and the isolation cylinder 2 are used to separate the space corresponding to the inlet pipe and the space corresponding to the outlet pipe. That is, the coolant entering through the inlet pipe enters the inlet cold chamber 21, and flows downward to the lower chamber through the first fuel assembly, and after being collected in the lower chamber, flows upward to the outlet hot chamber 22 through the second fuel assembly, and flows into the first accommodating chamber 14, so as to further flow out of the reactor through the outlet pipe.

[0047] The first fuel assembly and the second fuel assembly are hollow structures. One end of the first fuel assembly is connected to the first guide cylinder assembly 32, and the other end is connected to the lower chamber at the bottom of the lower plate of the core. One end of the second fuel assembly is connected to the second guide cylinder assembly 33, and the other end is connected to the lower chamber at the bottom of the lower plate of the core. The first-process coolant flows to the first fuel assembly through the first guide cylinder assembly 32 and flows to the lower chamber through the first fuel assembly. The coolant collected in the lower chamber flows upward as the second-process coolant through the second fuel assembly and reaches the outlet hot chamber 22.

[0048] That is, the isolation tube 2 is used to distinguish the coolant flow channels of the first process and the second process. One end of the isolation tube 2 is connected to the isolation plate 13, and the other end extends through the upper plate 18 of the core to the lower plate of the core and is connected to the lower chamber. In this way, the coolant with a lower inlet temperature outside the isolation tube 2 is combined with the first fuel assembly to be heated as the first process coolant and transported to the lower chamber. After being collected in the lower chamber, it is heated by the second fuel assembly as the second process coolant and transported to the outlet hot chamber 22, and finally discharged through the outlet connecting pipe.

[0049] The isolation tube 2 of the present invention cooperates with the compression tube 1 to separate the coolant with a relatively low temperature entering the reactor from the hot coolant with a high temperature that flows out after being heated by the core, so as to meet the flow channel design requirements of the dual flow path.

[0050] Please refer to Figure 1The compression cylinder 1 is provided with at least one flow hole 16, which is connected to the second accommodating chamber 15 and the inlet pipe. The compression cylinder 1 is also provided with at least one discharge hole 17, which is connected to the outlet pipe and the first accommodating chamber 14 respectively.

[0051] Specifically, multiple rows of flow units are arranged at intervals along the circumference of the compression cylinder 1, and each flow unit is provided with at least one flow hole 16 along the axial direction of the compression cylinder 1. Here, each flow unit includes three flow holes 16 as an example for explanation, and the specific number and arrangement of the flow holes 16 are not limited here.

[0052] Correspondingly, the number of the water holes 131 is consistent with the number of the outlet pipes, which is not limited here.

[0053] Please refer to Figures 1 to 4 The isolation plate 13 is provided with at least one water flow hole 131 on the inner side of the isolation cylinder 2 , and the water flow hole 131 is connected with the first accommodating chamber 14 and the outlet heat chamber 22 .

[0054] Furthermore, a core upper plate 18 is provided at the bottom of the compression cylinder 1, and a second accommodating chamber 15 is provided between the core upper plate 18 and the isolation plate 13; the guide cylinder assembly 3 is provided with at least one conducting hole 31 on the upper part of the core upper plate 18, and the conducting hole 31 is used to introduce or discharge the coolant in the guide cylinder assembly 3.

[0055] It can be seen that the guide tube assembly 3 is provided with a conducting hole 31 (see below) at the top of the core upper plate 18, so that the heated coolant flows to the outlet hot chamber 22 through the conducting hole 31, and is discharged into the first accommodating chamber 14 through the water flow hole 131, and finally discharged to the outside of the reactor through the outlet connecting pipe.

[0056] Alternatively, in some other embodiments, the guide tube assembly 3 opens a conducting hole 31 above the isolation plate 13, so that the coolant heated by the second fuel assembly can directly reach the first accommodating cavity 14 and be directly discharged from the outlet pipe.

[0057] Alternatively, please refer to Figure 7 In some other embodiments, the guide tube assembly 3 has guide holes 31 above the core upper plate 18 and above the isolation plate 13, thereby improving the discharge efficiency of the hot coolant. Figure 7 The opening position of the middle via hole 31 can be adjusted according to different implementations and is not limited here.

[0058] In one embodiment, the guide tube assembly 3 includes at least one first guide tube assembly 32 and at least one second guide tube assembly 33; the first guide tube assembly 32 is located on the outside of the isolation tube 2, and one end is connected to the support plate 11, and the other end is connected to the upper plate 18 of the core and is connected to the first fuel assembly to lead a process coolant from the inlet pipe to the lower chamber; the second guide tube assembly 33 is located on the inside of the isolation tube 2, and one end is connected to the support plate 11, and the other end is connected to the upper plate 18 of the core and is connected to the second fuel assembly to lead the coolant in the lower chamber to the outlet hot chamber 22.

[0059] The first guide tube assemblies 32 are evenly distributed in the outer space of the isolation tube 2, so as to evenly transport the coolant flowing in through the inlet pipe to the first fuel assembly.

[0060] Correspondingly, the second guide cylinder assemblies 33 are evenly distributed in the inner space of the isolation cylinder 2, so that the coolant collected in the lower chamber is transported to the outlet heat chamber 22 through multiple second guide cylinder assemblies 33 and merged, and finally discharged outward through the first accommodating chamber 14 and the outlet pipe.

[0061] In one embodiment, the core upper plate 18 is sealed and connected to the compression barrel 1. For example, the core upper plate 18 is sealed and connected to the compression barrel 1 by welding, so as to prevent the cold and hot fluids from mixing through the gap and affecting the temperature of the outlet hot coolant.

[0062] It can be seen that a first thermal insulation coating 19 is provided on the outer peripheral wall of the isolation tube 2 ; and a second thermal insulation coating 132 is provided on the lower surface of the isolation plate 13 located on the isolation tube 2 .

[0063] The isolation plate 13 and the isolation cylinder 2 are mainly used to isolate hot and cold fluids. The temperature of the inlet coolant is much lower than the temperature of the outlet coolant. The temperature difference between the inlet and outlet coolants is large. If thermal insulation is not performed, heat will be dissipated into the inlet cold chamber 21 through the isolation plate 13 and the isolation cylinder 2, reducing thermal efficiency.

[0064] Therefore, the present invention sets a first thermal insulation coating 19 on the outer wall of the isolation tube 2, and sets a second thermal insulation coating 132 on the inner side of the isolation plate 13 and at a position outside the isolation tube 2, so as to reduce the heat loss of the coolant through the isolation plate 13 and the isolation tube 2 after heating, thereby improving thermal efficiency.

[0065] Optionally, the thermal insulation coating is a thermal barrier coating to meet the thermal insulation requirements. In some other embodiments, other thermal insulation coating materials may also be used, which are not limited here.

[0066] Please refer to Figure 5 and Figure 6The isolation plate 13 includes an installation outer plate 133 and a matching inner plate 134; a matching groove 135 is opened in the middle of the installation outer plate 133, and one end cover of the matching inner plate 134 is arranged in the matching groove 135 and installed above the installation outer plate 133.

[0067] Furthermore, the matching inner plate 134 is connected to the mounting outer plate 133 via at least one threaded connector 136 ; a light hole matching with the threaded connector is provided on the matching inner plate 134 , and the threaded connector 136 forms a buffer gap 137 with the mounting inner plate 134 in the light hole.

[0068] It can be seen that the temperature of the middle part of the isolation plate 13 is higher than that of the outer ring. At high temperatures, the middle part is prone to arching, resulting in greater thermal deformation and thermal stress.

[0069] Therefore, the present invention divides the isolation plate 13 into an installation outer plate 133 and a matching inner plate 134 that cooperate with each other, and one end cover of the matching inner plate 134 is arranged in the matching groove 135 and cooperates with the radial clearance of the installation outer plate 133, so that the buffer gap 137 can absorb the radial thermal expansion difference between the installation outer plate 133 and the matching inner plate 134, thereby protecting the matching inner plate 134 and the installation outer plate 133 from excessive thermal deformation and thermal stress.

[0070] The coolant flow path of the present invention is as follows:

[0071] The coolant flows to the inlet cold chamber 21 through the reactor inlet pipe, and after being mixed in the inlet cold chamber 21, flows downward to the lower chamber through the first guide cylinder assembly 32 and the first fuel assembly as a process coolant, wherein a flow limiting device, such as a one-way valve, is arranged on the top of the first guide cylinder assembly 32 and the second guide cylinder assembly 33, so that the coolant will not flow upward to the top cover area of ​​the pressure vessel.

[0072] When the first-process coolant reaches the lower chamber, the merged coolant flows upward as the second-process coolant through the second fuel assembly and the second guide tube assembly 33 to the outlet hot chamber 22, and after being fully mixed in the outlet hot chamber 22, flows to the first accommodating chamber 14, and after being further mixed evenly in the first accommodating chamber 14, is discharged to the outside of the reactor through the outlet pipe connected to the first accommodating chamber 14.

[0073] The present invention also provides a supercritical water-cooled reactor, comprising a pressure vessel and the above-mentioned upper internals, wherein the upper internals are installed in the pressure vessel.

[0074] In summary, the upper in-core components of the present invention, the compression cylinder 1 and the isolation cylinder 2 can cooperate to separate the coolant with a lower temperature entering the pressure vessel from the coolant with a higher temperature that is heated by the core and flows out of the pressure vessel, thereby meeting the flow channel separation requirements of the dual-flow design.

[0075] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "install", "connect", "connect", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can also be a mechanical connection. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0076] The present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or multiple times in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0077] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. An upper internal component, characterized in that: include: A compression cylinder, with a support plate on the top, a containing space inside the compression cylinder, and a separation plate in the compression cylinder, the separation plate divides the containing space into a first containing chamber and a second containing chamber along the axial direction of the compression cylinder, the first containing chamber is connected to the outlet pipe, and the second containing chamber is connected to the inlet pipe; An isolation cylinder is axially arranged in the accommodating space along the compression cylinder and one end of the isolation cylinder is connected to the isolation plate. The second accommodating chamber includes an inlet cold chamber formed by the outer side of the isolation cylinder and the compression cylinder, and an outlet hot chamber inside the isolation cylinder; wherein, At least two guide cylinder assemblies are radially arranged on the compression cylinder, at least one of the at least two guide cylinder assemblies is inserted into the isolation cylinder, and the remaining guide cylinder assemblies are inserted outside the isolation cylinder.

2. The upper internals according to claim 1, characterized in that: The compression cylinder is provided with at least one flow hole, and the flow hole is connected with the second accommodating chamber and the inlet pipe; The compression cylinder is also provided with at least one discharge hole, which is communicated with the outlet pipe and the first accommodating chamber respectively.

3. The upper internals according to claim 1, characterized in that: The isolation plate is provided with at least one water flow hole on the inner side of the isolation cylinder, and the water flow hole is communicated with the first accommodating chamber and the outlet heat chamber.

4. The upper internals according to claim 1, characterized in that: The bottom of the compression cylinder is also provided with a core upper plate, and the second accommodating cavity is between the core upper plate and the isolation plate; The guide tube assembly is provided with at least one conducting hole on the upper portion of the core upper plate, and the conducting hole is used for introducing or discharging the coolant in the guide tube assembly.

5. The upper internals according to claim 4, characterized in that: The guide cylinder assembly includes at least one first guide cylinder assembly and at least one second guide cylinder assembly; The first guide tube assembly is located outside the isolation tube, and one end of the first guide tube assembly is connected to the support plate, and the other end is connected to the core upper plate and communicated with the first fuel assembly to guide a process coolant from the inlet pipe to the lower chamber; The second guide tube assembly is located inside the isolation tube, and one end is connected to the support plate, and the other end is connected to the core upper plate and communicated with the second fuel assembly to guide the second process coolant from the lower chamber to the outlet hot chamber.

6. The upper internals according to claim 4, characterized in that: The core upper plate is sealed and connected to the compression cylinder.

7. The upper internals according to claim 1, characterized in that: A first heat insulation coating is provided on the outer peripheral wall of the isolation cylinder; The isolation plate is located on the lower surface of the isolation cylinder and is provided with a second heat insulation coating.

8. The upper internals according to claim 7, characterized in that: The thermal insulation coating is a thermal barrier coating.

9. The upper internals according to claim 1, characterized in that: The isolation panel includes a mounting outer panel and a matching inner panel; A matching groove is provided in the middle of the installation outer plate, and one end cover of the matching inner plate is arranged in the matching groove and installed above the installation outer plate.

10. The upper internals according to claim 9, characterized in that: The mating inner plate is connected to the mounting outer plate by at least one threaded connection; The matching inner plate is provided with a light hole matched with the threaded connector, and the threaded connector forms a buffer gap with the mounting inner plate in the light hole.

11. A supercritical water-cooled reactor, characterized in that: include: A pressure vessel and an upper internals component according to any one of claims 1 to 10, wherein the upper internals component is installed in the pressure vessel.

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