Expansion water tank and circulating water expansion system
By installing a pressure monitoring and buffer unit in the expansion tank, the problems of corrosion in high-salt environments and lack of warning for excessive pressure are solved, enabling real-time pressure monitoring and protection, and extending service life.
Patent Information
- Application Number
- CN202422719647.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-07
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-11-07
AI Technical Summary
Expansion tanks are easily corroded by seawater in high-temperature, high-salt, and high-humidity environments such as ships and docks, and lack pressure gauges to warn of excessive pressure and potential safety hazards.
An expansion tank is designed, comprising an expansion unit, a liquid inlet unit, first and second pressure monitoring units, a buffer unit, an exhaust unit, and a control unit. The internal pressure is monitored by the first pressure monitoring unit, and a buffer unit is set between the first pressure monitoring unit and the expansion unit to protect the monitoring unit from corrosion and impact.
It effectively prevents the expansion tank from being damaged by seawater corrosion, can monitor pressure in real time to prevent excessive pressure, and improves safety and service life.
Smart Images
Figure CN223499895U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of refrigeration technology, and in particular to an expansion tank and a circulating water expansion system. Background Technology
[0002] An expansion tank is a crucial component in the water circulation system of a chiller unit. Its working principle involves storing and releasing water that expands due to temperature changes to maintain stable system pressure. When the system water temperature rises, the water volume expands, and some of this water is stored in the expansion tank to prevent excessive system pressure. When the system water temperature drops, the stored water in the expansion tank is released back into the system to replenish the volume lost due to cooling.
[0003] Expansion tanks are generally made of sheet metal, steel plate, or plastic. When refrigeration units are installed in high-temperature, high-salt, and high-humidity atmospheric environments such as ships, docks, and seawater in the user's water circulation system, ordinary expansion tanks are severely corroded. Furthermore, ordinary expansion tanks do not have pressure gauges or pressure displays, so they cannot serve as a warning.
[0004] Currently, no effective solutions have been proposed for the problems existing in the relevant technologies, such as the expansion tanks installed at the dock being easily corroded by seawater and the lack of pressure gauges to warn of excessive pressure and potential safety hazards. Utility Model Content
[0005] The purpose of this utility model is to address the shortcomings of existing technologies by providing an expansion tank that solves problems such as the ease with which expansion tanks installed at docks are corroded by seawater and the lack of pressure gauges to warn of excessive pressure, posing safety hazards.
[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0007] In a first aspect, an expansion tank is provided, comprising:
[0008] Expansion unit;
[0009] A liquid inlet unit is provided in the expansion unit and is connected to the circulating water pipeline, used to control the connection or disconnection of the circulating water pipeline and the expansion unit;
[0010] A first pressure monitoring unit, which is connected to the expansion unit, is used to monitor the internal pressure of the expansion unit;
[0011] A buffer unit is disposed between the first pressure monitoring unit and the expansion unit, and is connected to the expansion unit and the first pressure monitoring unit respectively, for buffering the impact of the measuring medium on the first pressure monitoring unit to protect the first pressure monitoring unit.
[0012] A second pressure monitoring unit, which is connected to the buffer unit, is used to monitor the pressure of the buffer unit;
[0013] An exhaust unit is connected to the expansion unit and the pressure relief pipeline, respectively, and is used to exhaust the gas from the expansion unit;
[0014] The control unit is connected to the liquid inlet unit, the first pressure monitoring unit, and the second pressure monitoring unit, respectively, and is used to control the opening or closing of the liquid inlet unit.
[0015] In some embodiments, the expansion unit includes:
[0016] An expansion element is connected to the liquid inlet unit, the buffer unit, and the exhaust unit, respectively.
[0017] A first connecting element is disposed at the bottom of the expansion element and connected to the liquid inlet unit;
[0018] A second connecting element is disposed on top of the expansion element and connected to the buffer unit;
[0019] A third connecting element is disposed on top of the expansion element and connected to the exhaust unit.
[0020] In some embodiments, the liquid inlet unit includes:
[0021] A liquid inlet element, which is connected to the expansion unit and the circulating water pipeline respectively;
[0022] A first switching element is disposed on the liquid inlet element and connected to the control unit, for controlling the connection or disconnection of the circulating water pipeline and the expansion unit.
[0023] In some embodiments, the liquid inlet unit further includes:
[0024] A sealing element is disposed between the liquid inlet element and the expansion unit to prevent leakage.
[0025] In some embodiments, the first pressure monitoring unit includes:
[0026] A first pressure monitoring element, which is connected to the buffer unit and the control unit, is used to monitor the internal pressure of the expansion unit.
[0027] In some embodiments, the buffer unit includes:
[0028] A buffer element is disposed between the first pressure monitoring unit and the expansion unit, and is connected to the expansion unit, the first pressure monitoring unit and the second pressure monitoring unit respectively, for buffering the impact of the measuring medium on the first pressure monitoring unit to protect the first pressure monitoring unit;
[0029] A second switching element is disposed between the buffer element and the expansion unit, and is used to control the connection or disconnection between the buffer element and the expansion unit.
[0030] In some embodiments, the second pressure monitoring unit includes:
[0031] A second pressure monitoring element is connected to the buffer unit and the control unit, and is used to monitor the pressure of the buffer unit.
[0032] In some embodiments, the exhaust unit includes:
[0033] An exhaust element, which is connected to the expansion unit, is used to exhaust the gas from the expansion unit;
[0034] A third switching element is disposed on the exhaust element and connected to the expansion unit, the control unit, and the pressure relief pipeline, respectively, for turning the exhaust element on or off.
[0035] In some of these embodiments, it also includes:
[0036] An installation unit is disposed on the outside of the expansion unit and is used to install the expansion unit.
[0037] Secondly, a circulating water expansion system is provided, comprising:
[0038] The expansion tank as described in the first aspect;
[0039] A circulating water pipeline, wherein the circulating water pipeline is connected to the liquid inlet unit of the expansion tank;
[0040] A pressure relief pipeline is connected to the venting unit of the expansion tank.
[0041] The present invention adopts the above technical solution and has the following technical effects compared with the prior art:
[0042] This utility model discloses an expansion tank and a circulating water expansion system. By setting a first pressure monitoring unit in the expansion unit, the internal pressure of the expansion unit can be monitored, which can prevent the expansion unit from being damaged due to excessive pressure. At the same time, a buffer unit is set between the first pressure monitoring unit and the expansion unit to protect the first pressure monitoring unit from the impact of the measuring medium and extend its service life. This solves the problems of expansion tanks installed at docks being easily corroded by seawater and lacking pressure gauges to warn of excessive pressure and potential safety hazards. Attached Figure Description
[0043] Figure 1 This is a schematic diagram (a) of an expansion tank according to an embodiment of the present utility model;
[0044] Figure 2 This is a schematic diagram of the expansion unit according to an embodiment of the present utility model;
[0045] Figure 3 This is a schematic diagram of the liquid inlet unit according to an embodiment of the present utility model;
[0046] Figure 4 This is a schematic diagram of the first pressure monitoring unit according to an embodiment of the present utility model;
[0047] Figure 5 This is a schematic diagram of a buffer unit according to an embodiment of the present utility model;
[0048] Figure 6 This is a schematic diagram of the second pressure monitoring unit according to an embodiment of the present utility model;
[0049] Figure 7 This is a schematic diagram of an exhaust unit according to an embodiment of the present utility model;
[0050] Figure 8 This is a schematic diagram (II) of the expansion tank according to an embodiment of the present utility model.
[0051] The attached diagram is labeled as follows: 100, expansion tank;
[0052] 110. Expansion unit; 111. Expansion element; 112. First connecting element; 113. Second connecting element; 114. Third connecting element;
[0053] 120. Liquid inlet unit; 121. Liquid inlet element; 122. First switching element; 123. Sealing element;
[0054] 130. First pressure monitoring unit; 131. First pressure monitoring element;
[0055] 140. Buffer unit; 141. Buffer element; 142. Second switching element;
[0056] 150. Second pressure monitoring unit; 151. Second pressure monitoring element;
[0057] 160. Exhaust unit; 161. Exhaust element; 162. Third switching element;
[0058] 170. Control unit;
[0059] 180. Installation unit. Detailed Implementation
[0060] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0061] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.
[0062] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.
[0063] Example 1
[0064] This embodiment relates to the expansion tank of this utility model.
[0065] An illustrative embodiment of this utility model, such as Figure 1As shown, an expansion tank 100 includes an expansion unit 110, a liquid inlet unit 120, a first pressure monitoring unit 130, a buffer unit 140, a second pressure monitoring unit 150, an exhaust unit 160, and a control unit 170. The liquid inlet unit 120 is located within the expansion unit 110 and connected to the circulating water pipeline, used to control the connection or closure of the circulating water pipeline and the expansion unit 110; the first pressure monitoring unit 130 is connected to the expansion unit 110 and used to monitor the internal pressure of the expansion unit 110; the buffer unit 140 is located between the first pressure monitoring unit 130 and the expansion unit 110, and is connected to both the expansion unit 110 and the first pressure monitoring unit 130, used to buffer the impact of the measuring medium on the first pressure monitoring unit 130 to protect it; the second pressure monitoring unit 150 is connected to the buffer unit 140 and used to monitor the pressure of the buffer unit 140; the exhaust unit 160 is connected to the expansion unit 110 and the pressure relief pipeline, used to exhaust the gas from the expansion unit 110; and the control unit 170 is connected to the liquid inlet unit 120, the first pressure monitoring unit 130, and the second pressure monitoring unit 150, used to control the opening or closing of the liquid inlet unit 120.
[0066] In some embodiments, the control unit 170 includes, but is not limited to, a microcontroller.
[0067] like Figure 2 As shown, the expansion unit 110 includes an expansion element 111, a first connecting element 112, a second connecting element 113, and a third connecting element 114. The expansion element 111 is connected to the liquid inlet unit 120, the buffer unit 140, and the venting unit 160. The first connecting element 112 is located at the bottom of the expansion element 111 and is connected to the liquid inlet unit 120. The second connecting element 113 is located at the top of the expansion element 111 and is connected to the buffer unit 140. The third connecting element 114 is located at the top of the expansion element 111 and is connected to the venting unit 160.
[0068] In some embodiments, the expansion element 111 includes a tube body and two caps. The tube body is provided with a first connecting element 112, a second connecting element 113 and a third connecting element 114, and is respectively connected to the liquid inlet unit 120, the buffer unit 140 and the venting unit 160; the two caps are respectively disposed at the ends of the tube body for sealing the tube body.
[0069] In some of these embodiments, the cross-section of the tube is circular.
[0070] In some of these embodiments, the expansion element 111 is made of a corrosion-resistant material, including but not limited to titanium alloys.
[0071] In some of these embodiments, the expansion element 111 is an expansion tank.
[0072] In some of these embodiments, the first connecting element 112 is integrally formed with the expansion element 111.
[0073] In some of these embodiments, the first connecting element 112 has a circular cross-section.
[0074] In some of these embodiments, the first connecting element 112 is made of a corrosion-resistant material, including but not limited to titanium alloy.
[0075] In some of these embodiments, the first connecting element 112 is a liquid inlet pipe.
[0076] In some of these embodiments, the second connecting element 113 is integrally formed with the expansion element 111.
[0077] In some of these embodiments, the cross-section of the second connecting element 113 is annular.
[0078] In some of these embodiments, the second connecting element 113 is made of a corrosion-resistant material, including but not limited to titanium alloy.
[0079] In some of these embodiments, the second connecting element 113 is a first threaded connector.
[0080] In some of these embodiments, the third connecting element 114 is integrally formed with the expansion element 111.
[0081] In some of these embodiments, the cross-section of the third connecting element 114 is annular.
[0082] In some of these embodiments, the third connecting element 114 is made of a corrosion-resistant material, including but not limited to titanium alloy.
[0083] In some of these embodiments, the third connecting element 114 is a second threaded connector.
[0084] like Figure 3 As shown, the liquid inlet unit 120 includes a liquid inlet element 121 and a first switching element 122. The liquid inlet element 121 is connected to the expansion unit 110 and the circulating water pipeline, respectively. The first switching element 122 is disposed on the liquid inlet element 121 and connected to the control unit 170, and is used to control the connection or disconnection of the circulating water pipeline and the expansion unit 110.
[0085] Specifically, the liquid inlet element 121 is connected to the first connecting element 112.
[0086] In some of these embodiments, the liquid inlet element 121 is connected to the first connecting element 112 via a flange.
[0087] In some of these embodiments, the liquid inlet element 121 is made of corrosion-resistant materials, including but not limited to titanium alloys.
[0088] In some of these embodiments, the inlet element 121 is a flange connector.
[0089] In some of these embodiments, the first switching element 122 is communicatively connected to the control unit 170.
[0090] In some embodiments, the connection between the first switching element 122 and the liquid inlet element 121 is not limited to integral molding.
[0091] In some of these embodiments, the first switching element 122 is a shut-off valve.
[0092] Furthermore, the liquid inlet unit 120 also includes a sealing element 123. The sealing element 123 is disposed between the liquid inlet element 121 and the expansion unit 110 to prevent leakage.
[0093] Specifically, the sealing element 123 is disposed between the liquid inlet element 121 and the first connecting element 112.
[0094] The dimensions of the sealing element 123 are matched with the dimensions of the liquid inlet element 121 (first connecting element 112). Generally, the radial dimension of the outer contour of the sealing element 123 is equal to the radial dimension of the outer contour of the liquid inlet element 121 (first connecting element 112), and the radial dimension of the inner contour of the sealing element 123 is greater than the radial dimension of the inner contour of the liquid inlet element 121 (first connecting element 112).
[0095] In some of these embodiments, the sealing element 123 has an annular cross-section.
[0096] In some of these embodiments, the sealing element 123 includes, but is not limited to, a PTFE gasket.
[0097] like Figure 4 As shown, the first pressure monitoring unit 130 includes a first pressure monitoring element 131. The first pressure monitoring element 131 is connected to the buffer unit 140 and the control unit 170, and is used to monitor the internal pressure of the expansion unit 110.
[0098] Specifically, the first pressure monitoring element 131 is connected to the expansion element 111.
[0099] In some of these embodiments, the first pressure monitoring element 131 is communicatively connected to the control unit 170.
[0100] In some of these embodiments, the first pressure monitoring element 131 is a pressure gauge.
[0101] like Figure 5 As shown, the buffer unit 140 includes a buffer element 141 and a second switching element 142. The buffer element 141 is disposed between the first pressure monitoring unit 130 and the expansion unit 110, and is connected to the expansion unit 110, the first pressure monitoring unit 130, and the second pressure monitoring unit 150 respectively, to buffer the impact of the measuring medium on the first pressure monitoring unit 130 to protect it. The second switching element 142 is disposed between the buffer element 141 and the expansion unit 110, and is used to control the connection or disconnection between the buffer element 141 and the expansion unit 110.
[0102] Specifically, the buffer element 141 is disposed between the expansion element 111 and the first pressure monitoring element 131, and is connected to the second connecting element 113 and the first pressure monitoring element 131 respectively; the second switching element 142 is disposed between the buffer element 141 and the second connecting element 113.
[0103] In some of these embodiments, the cross-section of the buffer element 141 is helical.
[0104] In some of these embodiments, the buffer element 141 is a buffer tube.
[0105] In some of these embodiments, the second switching element 142 is connected to the second connecting element 113 by a thread.
[0106] In some embodiments, the connection between the second switching element 142 and the buffer element 141 includes, but is not limited to, a threaded connection.
[0107] In some of these embodiments, the second switching element 142 is a pressure gauge valve.
[0108] like Figure 6 As shown, the second pressure monitoring unit 150 includes a second pressure monitoring element 151. The second pressure monitoring element 151 is connected to the buffer unit 140 and the control unit 170, and is used to monitor the pressure of the buffer unit 140.
[0109] Specifically, the second pressure monitoring element 151 is connected to the buffer element 141 and is used to monitor the pressure of the buffer element 141.
[0110] In some of these embodiments, the second pressure monitoring element 151 is communicatively connected to the control unit 170.
[0111] In some of these embodiments, the second pressure monitoring element 151 is a pressure sensor.
[0112] like Figure 7As shown, the exhaust unit 160 includes an exhaust element 161 and a third switching element 162. The exhaust element 161 is connected to the expansion unit 110 and is used to exhaust the gas inside the expansion unit 110. The third switching element 162 is disposed on the exhaust element 161 and is connected to the expansion unit 110 and the pressure relief pipeline, respectively, and is used to open or close the exhaust element 161 and the pressure relief pipeline.
[0113] Specifically, the exhaust element 161 is connected to the expansion element 111; the third switching element 162 is connected to the third connecting element 114.
[0114] In some embodiments, the exhaust element 161 includes an exhaust pipe and an exhaust valve. A first end of the exhaust pipe is connected to a third switching element 162; the exhaust valve is located at a second end of the exhaust pipe.
[0115] In some embodiments, the third switching element 162 is threadedly connected to the exhaust element 161 and the third connecting element 114.
[0116] In some embodiments, the third switching element 162 is a three-way valve, including but not limited to a three-way ball valve.
[0117] The method of using this utility model is as follows:
[0118] When the water circulation system of the refrigeration unit is shut down, the measuring medium in the expansion element 111 does not enter the buffer element 141, and the value of the first pressure monitoring element 131 is the initial value.
[0119] When the water circulation system of the chiller unit is turned on, the circulating water expands due to heat and enters the expansion element 111 through the circulating water pipeline.
[0120] The measuring medium (such as gas) inside the expansion element 111 is squeezed by circulating water and comes into contact with the first pressure monitoring element 131 via the buffer element 141. The first pressure monitoring element 131 displays the pressure value inside the expansion element 111.
[0121] Simultaneously, the measuring medium (such as gas) comes into contact with the second pressure monitoring element 151 via the buffer element 141. When the pressure on the second pressure monitoring element 151 is greater than the set value, it sends a signal to the control unit 170, and the control unit 170 controls the first switching element 122 to close.
[0122] The advantages of this invention are that by setting a first pressure monitoring unit in the expansion unit, the pressure inside the expansion unit can be monitored, which can prevent the expansion unit from being damaged due to excessive pressure. At the same time, a buffer unit is set between the first pressure monitoring unit and the expansion unit to protect the first pressure monitoring unit from the impact of the measuring medium and extend its service life. This solves the problems of expansion tanks installed at docks being easily corroded by seawater and the lack of pressure gauges to warn of excessive pressure and potential safety hazards.
[0123] Example 2
[0124] This embodiment is a supplementary embodiment to Embodiment 1.
[0125] like Figure 8 As shown, the expansion tank 100 also includes an installation unit 180. The installation unit 180 is disposed on the outside of the expansion unit 110 and is used to install the expansion unit 110.
[0126] Specifically, the mounting unit 180 is disposed on the outside of the expansion element 111 and is used to mount the expansion element 111.
[0127] In some embodiments, the connection between the mounting unit 180 and the expansion element 111 includes, but is not limited to, welding.
[0128] In some embodiments, the mounting unit 180 includes at least two support elements and at least two mounting elements. The two support elements are horizontally arranged and parallel to each other; the two mounting elements are vertically arranged outside the two support elements, and the ends of the two mounting elements are respectively connected to the two support elements.
[0129] In some of these embodiments, the support element has an L-shaped cross-section.
[0130] In some of these embodiments, the support elements include, but are not limited to, metal corner brackets.
[0131] In some embodiments, the connection methods between the mounting element and the bracket element include, but are not limited to, welding and screw connection.
[0132] In some of these embodiments, the cross-section of the mounting element is arc-shaped.
[0133] In some of these embodiments, the mounting element is a metal bracket.
[0134] In some embodiments, there are two mounting units 180. The two mounting units 180 are symmetrically arranged at the rear of the expansion element 111.
[0135] In some of these embodiments, the mounting unit 180 is a titanium alloy bracket.
[0136] Example 3
[0137] This embodiment relates to the circulating water expansion system of this utility model.
[0138] An illustrative embodiment of this utility model discloses a circulating water expansion system, comprising an expansion tank 100, a circulating water pipeline, and a pressure relief pipeline as described in Embodiments 1 and 2. The circulating water pipeline is connected to the liquid inlet unit 120 of the expansion tank 100; the pressure relief pipeline is connected to the venting unit 160 of the expansion tank 100.
[0139] Specifically, the circulating water pipeline is connected to the liquid inlet element 121; the pressure relief pipeline is connected to the vent element 161.
[0140] The usage method of this embodiment is basically the same as that of Embodiments 1 to 2, and will not be repeated here.
[0141] The technical effects of this embodiment are basically the same as those of Embodiments 1 and 2, and will not be repeated here.
[0142] The above description is only a preferred embodiment of the present utility model and does not limit the implementation method and protection scope of the present utility model. Those skilled in the art should realize that all solutions obtained by equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.
Claims
1. An expansion tank for use in a marine refrigeration unit, characterized in that, include: Expansion unit; A liquid inlet unit is provided in the expansion unit and is connected to the circulating water pipeline, used to control the connection or disconnection of the circulating water pipeline and the expansion unit; A first pressure monitoring unit, which is connected to the expansion unit, is used to monitor the internal pressure of the expansion unit; A buffer unit is disposed between the first pressure monitoring unit and the expansion unit, and is connected to the expansion unit and the first pressure monitoring unit respectively, for buffering the impact of the measuring medium on the first pressure monitoring unit to protect the first pressure monitoring unit. A second pressure monitoring unit, which is connected to the buffer unit, is used to monitor the pressure of the buffer unit; An exhaust unit is connected to the expansion unit and the pressure relief pipeline, respectively, and is used to exhaust the gas from the expansion unit; The control unit is connected to the liquid inlet unit, the first pressure monitoring unit, and the second pressure monitoring unit, respectively, and is used to control the opening or closing of the liquid inlet unit.
2. The expansion tank according to claim 1, characterized in that, The expansion unit includes: An expansion element is connected to the liquid inlet unit, the buffer unit, and the exhaust unit, respectively. A first connecting element is disposed at the bottom of the expansion element and connected to the liquid inlet unit; A second connecting element is disposed on top of the expansion element and connected to the buffer unit; A third connecting element is disposed on top of the expansion element and connected to the exhaust unit.
3. The expansion tank according to claim 1, characterized in that, The liquid inlet unit includes: A liquid inlet element, which is connected to the expansion unit and the circulating water pipeline respectively; A first switching element is disposed on the liquid inlet element and connected to the control unit, for controlling the connection or disconnection of the circulating water pipeline and the expansion unit.
4. The expansion tank according to claim 3, characterized in that, The liquid inlet unit further includes: A sealing element is disposed between the liquid inlet element and the expansion unit to prevent leakage.
5. The expansion tank according to claim 1, characterized in that, The first pressure monitoring unit includes: A first pressure monitoring element, which is connected to the buffer unit and the control unit, is used to monitor the internal pressure of the expansion unit.
6. The expansion tank according to claim 1, characterized in that, The buffer unit includes: A buffer element is disposed between the first pressure monitoring unit and the expansion unit, and is connected to the expansion unit, the first pressure monitoring unit and the second pressure monitoring unit respectively, for buffering the impact of the measuring medium on the first pressure monitoring unit to protect the first pressure monitoring unit; A second switching element is disposed between the buffer element and the expansion unit, and is used to control the connection or disconnection between the buffer element and the expansion unit.
7. The expansion tank according to claim 1, characterized in that, The second pressure monitoring unit includes: A second pressure monitoring element is connected to the buffer unit and the control unit, and is used to monitor the pressure of the buffer unit.
8. The expansion tank according to claim 1, characterized in that, The exhaust unit includes: An exhaust element, which is connected to the expansion unit, is used to exhaust the gas from the expansion unit; A third switching element is disposed on the exhaust element and connected to the expansion unit, the control unit, and the pressure relief pipeline, respectively, for turning the exhaust element on or off.
9. The expansion tank according to any one of claims 1 to 8, characterized in that, Also includes: An installation unit is disposed on the outside of the expansion unit and is used to install the expansion unit.
10. An expansion tank system for use in marine refrigeration units, characterized in that, include: The expansion tank as described in any one of claims 1 to 9; A circulating water pipeline, wherein the circulating water pipeline is connected to the liquid inlet unit of the expansion tank; A pressure relief pipeline is connected to the venting unit of the expansion tank.