Heat exchanger with anti-corrosion structure and gas water heater

Abstract

The present invention relates to a heat exchanger with an anti-corrosion structure, comprising a copper shell, a copper heat exchange tube located in the shell, and a copper water inlet pipe and a water outlet pipe located outside the shell and connected to the heat exchange tube, and further comprising a flexible electronic anode and an anode controller. The flexible electronic anode extends into the heat exchange tube and matches the length and curved shape of the heat exchange tube, one end of the flexible electronic anode extends out of the heat exchange tube and is connected to the positive end of the anode controller, and the negative end of the anode controller is connected to the outer wall of the heat exchange tube. The portion of the flexible electronic anode located in the heat exchange tube has a structure in which a limiting insulating section and an exposed coating section alternately appear along the length direction, and the limiting insulating section can prevent the electronic anode from contacting the inner wall of the heat exchange tube. The advantage is that the flexible electronic anode extends into the curved and coiled heat exchange tube and the inlet and outlet water pipes, and electrons are excited by each exposed coating section of the electronic anode, thereby preventing corrosion of the heat exchange tube and the inlet and outlet water pipes.

Description

Technical Field

[0001] The invention relates to the field of corrosion protection of gas water heaters, and in particular to a heat exchanger and a gas water heater with an anti-corrosion structure. Background Art

[0002] The heat exchanger of a gas water heater is a component that transfers the heat of gas combustion to the water in the pipeline. It is usually composed of a water inlet pipe, a heat exchange straight pipe, a connecting elbow and a water outlet pipe connected in series to form a water flow channel. At the same time, heat exchange fins are fixed to the outside of the heat exchange straight pipe. The heat exchange straight pipe and heat exchange fins are located inside the copper heat exchanger shell and are directly heated by the burner. The water outlet pipe usually coils several times on the outside of the copper heat exchanger shell and then extends downward to form a hot water outlet.

[0003] In the prior art, since the heat exchanger of the gas water heater is composed of a relatively thin copper tube to form the water flow channel, effective anti-corrosion measures are generally not taken, but the tube is allowed to corrode until perforation and leakage occur and then replaced. The main reason for not taking anti-corrosion measures is that the copper tube is relatively thin, and its diameter is usually 10-15mm. Water flows in the tube, and corrosion occurs from the inside of the tube. Part of the copper tube will be heated by the burner, and the inner wall of the tube is not easy to be anti-corroded. At the same time, the conventional electronic anode used for electrochemical anti-corrosion is usually hard and short. On the one hand, it cannot be effectively installed on the copper tube. On the other hand, the existing electronic anode is short, and the copper tube is relatively long. Even if the shorter electronic anode is forcibly installed on the copper tube, its anti-corrosion effect usually only applies to the shorter section of the copper tube, and the anti-corrosion effect is poor. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a heat exchanger and a gas water heater with an anti-corrosion structure, aiming to overcome the deficiency of conventional gas water heaters and heat exchangers thereof in the prior art that lack an effective anti-corrosion structure.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A heat exchanger with an anti-corrosion structure comprises a copper shell, a copper heat exchange tube located in the shell, and a copper water inlet pipe and a water outlet pipe located outside the shell and connected to the heat exchange tube. It also comprises a flexible electronic anode and an anode controller. The flexible electronic anode extends into the heat exchange tube and matches the length and bending shape of the heat exchange tube. One end of the flexible electronic anode extends outside the heat exchange tube and is electrically connected to the positive pole of the anode controller. The negative pole of the anode controller is electrically connected to the shell, the heat exchange tube, the water inlet pipe or the water outlet pipe. The part of the flexible electronic anode located in the heat exchange tube has a structure in which a limiting insulating section and an exposed coating section alternately appear along the length direction. The limiting insulating section can prevent the exposed coating section from contacting the inner wall of the heat exchange tube.

[0006] Based on the above technical solution, the present invention can also be improved as follows.

[0007] Furthermore, the limiting insulating section is an insulating plastic sleeve sleeved on the flexible electronic anode.

[0008] The advantage of adopting the above-mentioned further structural improvement is that the insulating plastic sleeve can be easily set outside the flexible electronic anode, has a simple structure, and is easy to process and realize; the insulating plastic sleeve can insulate the flexible electronic anode from the heat exchange tube, ensuring that the anode is not connected to the heat exchange tube, and ensuring that the heat exchange tube is the cathode.

[0009] Furthermore, the limiting insulating section also includes a plurality of limiting rings, and the limiting rings are sleeved and fixed on the insulating plastic sleeve.

[0010] The advantage of adopting the above further improvement is that the limiting collar can limit the flexible electronic anode and effectively prevent the exposed coating section from contacting the inner wall of the heat exchange tube.

[0011] Furthermore, the limiting ring includes an outer support ring, an inner fixed ring and a plurality of radially extending spokes, the two ends of the spokes are respectively connected to the outer support ring and the inner fixed ring, the inner fixed ring is sleeved and fixed on the insulating plastic sleeve, and the outer support ring is gap-matched with the inner wall of the heat exchange tube.

[0012] The advantage of adopting the above-mentioned further structural improvement is that the inner and outer support rings are connected by spokes, and the space between the spokes is a channel for water to flow through, which can effectively limit the flexible electronic anode and ensure that the water flow resistance is reduced and the impact of the water flow on the flexible electronic anode wire is reduced.

[0013] Furthermore, the limiting collar is fixed to a position of the insulating plastic sleeve adjacent to the exposed coating section.

[0014] The advantage of adopting the above further structural improvement is that the exposed coating section can be supported and lifted up by the limiting collars at both ends, thereby effectively avoiding contact with the tube wall of the heat exchange tube.

[0015] Furthermore, the heat exchange tube is provided with an interface for the flexible electronic anode to extend into, and a sealing cover is detachably connected to the interface, and the flexible electronic anode is insulated and passes through the sealing cover.

[0016] The advantage of adopting the above-mentioned further structural improvement is that it facilitates the initial insertion of the flexible electronic anode into the interior of the heat exchange tube.

[0017] Furthermore, the heat exchange tube, water inlet pipe and water outlet pipe are different sections of the same copper tube, the number of the flexible electronic anode is one and it passes through the water inlet pipe, heat exchange tube and water outlet pipe in sequence, and the heat exchange tube, water inlet pipe and water outlet pipe are respectively electrically connected to the negative pole of the anode controller through wires.

[0018] The advantage of adopting the above-mentioned further structural improvement is that it is helpful to reduce the number of interfaces opened on the copper tube, the processing cost is low, and the risk of leakage is effectively reduced; when only one interface is set, the flexible electronic anode should be installed when the copper tube is a straight tube, and then the copper tube is bent.

[0019] Furthermore, there are a plurality of flexible electronic anode wires, and at least one flexible electronic anode is disposed in each of the heat exchange tube, the water inlet pipe and the water outlet pipe.

[0020] The advantage of adopting the above-mentioned further structural improvement is that it helps to ensure that each flexible electronic anode is of appropriate length and is as straight as possible, and it is convenient to install the flexible electronic anode after the copper tube is bent into shape.

[0021] Furthermore, the flexible electronic anode wire is made of corrosion-resistant titanium alloy or valve metal, and the diameter of the flexible electronic anode is 0.25-1 mm.

[0022] The present invention also provides a gas water heater having the above-mentioned heat exchanger.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] At present, there is no effective anti-corrosion method for the multi-bend heat exchanger of gas water heaters. The copper heat exchange tube of the heat exchanger has a flexible electronic anode electrically connected to the positive electrode of the anode controller. The negative electrode of the anode controller is electrically connected to the copper shell, the heat exchange tube or the inlet and outlet water pipes. When there is water in the heat exchange tube, a connecting loop is formed as a whole. The anode controller outputs a protection current through the flexible electronic anode according to the properties of the copper material, the temperature and water quality of the water in the heat exchange tube, and other factors, so as to implement effective cathodic protection for each pipe section. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of a heat exchanger with an anti-corrosion structure provided by the present invention;

[0026] Figure 2 For the present invention Figure 1 Schematic diagram of the heat exchange tube and the flexible electronic anode installed therein;

[0027] Figure 3 for Figure 2 A cross-sectional view of a heat exchange tube and a flexible electronic anode therein along AA;

[0028] Figure 4 for Figure 2 The enlarged schematic diagram of the circled area in the middle;

[0029] Figure 5 It is a schematic diagram of the flexible electronic anode being located in the heat exchange tube along the axial direction when the flexible electronic anode has a solid and relatively thin limiting collar;

[0030] Figure 6 This is a schematic diagram of the principle of the flexible electronic anode in the heat exchange tube to protect the heat exchange tube from corrosion (due to the action of the external anode controller, when the protection current is generated, there are surplus electrons at various locations on the heat exchange tube wall).

[0031] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0032] 1. Shell; 2. Heat exchange tube; 3. Water inlet pipe; 4. Water outlet pipe; 5. Flexible electronic anode; 6. Anode controller; 7. Limiting insulation section; 8. Exposed coating section; 9. Insulating plastic sleeve; 10. Limiting ring; 11. Outer support ring; 12. Inner fixing ring; 13. Spokes; 14. Interface; 15. Sealing cover. DETAILED DESCRIPTION

[0033] The principles and features of the present invention are described below in conjunction with the accompanying drawings and specific embodiments. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0034] In the description of the present invention, if terms indicating orientation such as "up", "down", "left", "right", "top", "bottom", "inside" and "outside" are used, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] like Figures 1 to 6 As shown, the present invention provides a heat exchanger with an anti-corrosion structure, comprising a copper shell 1, a copper heat exchange tube 2 located in the shell 1, and a copper water inlet pipe 3 and a water outlet pipe 4 located outside the shell 1 and connected to the heat exchange tube 2, and further comprising a flexible electronic anode 5 and an anode controller 6, wherein the flexible electronic anode 5 extends into the heat exchange tube 2 and matches the length and bending shape of the heat exchange tube 2, one end of the flexible electronic anode 5 extends out of the heat exchange tube 2 and is electrically connected to the positive electrode of the anode controller 6, and the negative electrode of the anode controller 6 is electrically connected to the shell 1, the heat exchange tube 2, the water inlet pipe 3 or the water outlet pipe 4, and the portion of the flexible electronic anode 5 located in the heat exchange tube 2 has a structure in which a limiting insulating section 7 and an exposed coating section 8 alternately appear along the length direction, and the limiting insulating section 7 is longer than the exposed coating section 8 and can prevent the exposed coating section 8 from contacting the inner wall of the heat exchange tube 2.

[0036] It should be noted that the diameter of the flexible electronic anode is much smaller than the inner diameter of the heat exchange tube, ensuring that it does not affect the flow of water in the tube, and the thinner and lighter flexible electronic anode can moderately disturb the water flow in the tube, reducing the probability of scaling in the tube. The flexible electronic anode includes an elongated anode core, which is made of corrosion-resistant metal, and insulating plastic sleeves are evenly spaced along the axial direction outside the anode core to form a limited insulating section, and between adjacent limited insulating sections is a bare coating section (that is, the core surface is coated with a precious metal coating such as platinum or iridium).

[0037] In one embodiment of the present invention, the limiting insulating section 7 is an insulating plastic sleeve 9 sleeved on the flexible electronic anode 5 .

[0038] It should be noted that the insulating plastic sleeve (insulating coating may also be considered) should have a certain heat resistance and corrosion resistance to ensure that it can be used inside the hot water pipe for a long time without being damaged or falling off.

[0039] In one embodiment of the present invention, the limiting insulating section 7 further includes a plurality of limiting rings 10 , and the limiting rings 10 are sleeved and fixed on the insulating plastic sleeve 9 .

[0040] It should be noted that the limiting collar can be as follows Figure 2 and 3 The larger support ring with water-permeable pores shown can also be Figure 5 Smaller solid ring shown.

[0041] In one embodiment of the present invention, Figure 3 As shown, the limiting ring 10 includes an outer supporting ring 11, an inner fixing ring 12 and a plurality of radially extending spokes 13, the two ends of the spokes 13 are respectively connected to the outer supporting ring 11 and the inner fixing ring 12, the inner fixing ring 12 is sleeved and fixed on the insulating plastic sleeve 9, and the outer supporting ring 11 is gap-matched with the inner wall of the heat exchange tube 2.

[0042] In one embodiment of the present invention, the limiting collar 10 is fixed to a position of the insulating plastic sleeve 9 adjacent to the exposed coating section 8 .

[0043] It should be noted that when the insulating plastic sleeve is thicker and the exposed coating section is shorter, the exposed coating section is not easy to contact with the copper tube wall, and the limiting ring may not be provided.

[0044] In one embodiment of the present invention, the heat exchange tube 2 is provided with an interface 14 for the flexible electronic anode 5 to extend into, and a detachably connected sealing cover 15 is provided at the interface 14, and the flexible electronic anode is insulated and passes through the sealing cover.

[0045] It should be noted that the function of the sealing cover is to prevent water in the tube from leaking out through the interface on the one hand, and to ensure that the flexible electronic anode can be electrically connected to the anode controller through a wire on the other hand. The sealing cover can be insulated from the heat exchange tube as a whole, and can also be insulated from the flexible electronic anode as a whole.

[0046] In one embodiment of the present invention, the heat exchange tube 2, the water inlet pipe 3 and the water outlet pipe 4 are different sections of the same copper pipe, the number of the flexible electronic anode 5 is one and it passes through the water inlet pipe 3, the heat exchange tube 2 and the water outlet pipe 4 in sequence, and the heat exchange tube 2, the water inlet pipe 3 and the water outlet pipe 4 are respectively electrically connected to the negative pole of the anode controller 6 through wires.

[0047] It can be understood that when there is only one full-length flexible electronic anode in the entire copper tube, the flexible electronic anode should be installed into the tube when the copper tube has not yet been installed into the shell and has not been bent and coiled outside the shell but is still a straight tube, and then the copper tube is installed and bent into shape, and the flexible electronic anode wire is bent into shape accordingly during bending.

[0048] In one embodiment of the present invention, there are a plurality of flexible electronic anodes 5 , and at least one flexible electronic anode is disposed in each of the heat exchange tube 2 , the water inlet pipe 3 , and the water outlet pipe 4 .

[0049] It can be understood that when the heat exchange tube is first installed on the heat exchanger shell and then the flexible electronic anode is installed, the method of this embodiment can be adopted, that is, multiple tubes are installed, each of which is installed on a relatively straight section of the copper tube. The advantage of this method is that it is easy to replace the flexible electronic anode.

[0050] In one embodiment of the present invention, the flexible electronic anode 5 is a corrosion-resistant titanium alloy wire or a valve metal, and the diameter of the flexible electronic anode 5 is 0.25-2 mm.

[0051] It should be noted that flexible electronics preferably use materials with good corrosion resistance to ensure their durability.

[0052] The present invention also provides a gas water heater having the above-mentioned heat exchanger.

[0053] The basic principle of the present invention is as follows: Figure 6As shown, the copper heat exchange tube 2 of the heat exchanger has a flexible electronic anode 5 electrically connected to the positive electrode of the anode controller 6, and the negative electrode of the anode controller is electrically connected to the copper shell, the heat exchange tube or the inlet and outlet water pipes. When there is water in the heat exchange tube, a connecting loop is formed as a whole. The anode controller outputs a protection current through the flexible electronic anode according to the properties of the copper material, the temperature of the water in the heat exchange tube, the water quality and other factors, so as to implement effective cathodic protection for each pipe section. The main feature of the present invention is that a thin wire with a diameter much smaller than the inner diameter of the copper tube is used as the electronic anode and can be arranged along the entire length of the copper tube, ensuring that the entire pipe section is acted upon by the electronic anode on each small pipe section and generates surplus electrons on the pipe wall, so that the entire pipe wall can be effectively protected.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A heat exchanger with an anti-corrosion structure, comprising a copper shell (1), a copper heat exchange tube (2) located in the shell (1), and a copper water inlet pipe (3) and a water outlet pipe (4) located outside the shell (1) and connected to the heat exchange tube (2), characterized in that: It also comprises a flexible electronic anode (5) and an anode controller (6), wherein the flexible electronic anode (5) extends into the heat exchange tube (2) and matches the protected length and bending shape of the heat exchange tube (2), one end of the flexible electronic anode (5) is connected to the positive electrode of the anode controller, and the other end or multiple ends thereof extend into various parts of the heat exchange tube (2), the negative electrode of the anode controller (6) is electrically connected to the outer wall of the shell (1) or the heat exchange tube (2) or the water inlet pipe (3) or the water outlet pipe (4), and the portion of the flexible electronic anode (5) located in the heat exchange tube (2) has a structure in which a limiting insulating section (7) and an exposed coating section (8) alternately appear along the length direction, and the limiting insulating section (7) prevents the exposed coating section (8) from contacting the inner wall of the heat exchange tube (2); A flexible electronic anode (5) is inserted into the heat exchange tube. The flexible electronic anode (5) is composed of a limited insulating section (7) and an exposed coating section (8). The limited insulating section (7) is a portion of the flexible electronic anode body coated with or covered with an insulating layer, and the exposed coating section (8) is a portion of the flexible electronic anode body coated with a precious metal layer; The heat exchange tube (2), the water inlet tube (3) and the water outlet tube (4) are different sections of the same copper tube. The number of the flexible electronic anode (5) is one and passes through the water inlet tube (3), the heat exchange tube (2) and the water outlet tube (4) in sequence. The heat exchange tube (2), the water inlet tube (3) and the water outlet tube (4) are respectively electrically connected to the negative electrode of the anode controller (6) via wires. The limiting insulating section (7) further comprises a plurality of limiting collars (10), wherein the limiting collars (10) are sleeved and fixed on the insulating plastic sleeve (9); The limiting collar (10) comprises an outer supporting ring (11), an inner fixing ring (12) and a plurality of radially extending spokes (13), the two ends of the spokes (13) being respectively connected to the outer supporting ring (11) and the inner fixing ring (12), the inner fixing ring (12) being sleeved and fixed on the insulating plastic sleeve (9), and the outer supporting ring (11) being gap-matched with the inner wall of the heat exchange tube (2); The heat exchange tube (2) is provided with an interface (14) for the flexible electronic anode (5) to extend into, a sealing cover (15) that is detachably connected to the interface (14), and the flexible electronic anode is insulated and connected to the positive electrode of the anode controller (6) through the sealing cover (15).

2. The heat exchanger with an anti-corrosion structure according to claim 1, characterized in that: There are a plurality of flexible electronic anodes (5), and each section of the heat exchange tube (2), the water inlet pipe (3) and the water outlet pipe (4) may be provided with a flexible electronic anode (5).

3. A heat exchanger with an anti-corrosion structure according to claim 1 or 2, characterized in that: The flexible electronic anode (5) is made of corrosion-resistant titanium alloy, and the diameter of the flexible electronic anode (5) is 0.25-2 mm.

4. The heat exchanger with an anti-corrosion structure according to claim 1, characterized in that: The limiting collar (10) is fixed to the position of the insulating plastic sleeve (9).

5. A gas water heater, characterized in that: A heat exchanger according to any one of claims 1 to 4.

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