Water preheating system for cylinder sleeve of diesel engine

Abstract

The invention relates to a diesel engine cylinder sleeve water preheating system which comprises a mixed heating assembly and a separation assembly, the mixed heating assembly is used for heating an oil-based medium in a steam and electric heating mode, and the mixed heating assembly comprises a box body, a spray head arranged in the box body and a steam heating pipe; and the separation assembly is used for extracting the oil-based medium mixture carrying water drops in the box body and separating the oil-based medium mixture through centrifugal force. According to the system, an oil-based medium is sprayed into liquid drops to be interactively heated with steam, the steam is condensed into water to be separated from the oil-based medium, the oil-based medium and the water drops are centrifugally separated and then connected with a heat exchanger, the heat exchanger is connected to a water cooling pipeline of a diesel engine cylinder sleeve in parallel, and cooling liquid in the water cooling pipeline is heated through heat exchange; therefore, impurities formed by steam can be prevented from scaling in the heat exchanger, and the heat exchange effect is prevented from being reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of diesel engine cylinder liner preheating equipment, and in particular relates to a diesel engine cylinder liner water preheating system. Background Art

[0002] The diesel engine cylinder liner and cylinder head together constitute the movement space of the piston. The piston reciprocates in its inner hole and is cooled by cooling water outside. The cylinder liner not only needs to be cooled when the diesel engine is running, but also needs to be preheated before starting, especially for large marine diesel engines. The preheating process is extremely important.

[0003] Chinese invention patent 201811002307.X discloses a hybrid heating preheating of diesel engine cylinder liner cooling water, which greatly reduces the heating energy consumption through a heating method that mixes steam and electric heating. The interactive heating method of steam and nozzles makes the contact area of ​​heat exchange between steam and droplets huge, and the heating efficiency is greatly improved. However, the interactive method of steam and droplets causes steam to condense into droplets when it is cold and mix into water, and the steam may carry water droplets in a saturated state. The water droplets come from the boiler and carry impurities. The impurities may enter the circulating water system and then enter the flow channel of the engine / heat exchanger, which is easy to scale in the flow channel of the engine / heat exchanger, resulting in a decrease in the preheating effect. Summary of the invention

[0004] The purpose of the present invention is to provide a diesel engine cylinder jacket water preheating system in order to solve the above-mentioned problem.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0006] A diesel engine cylinder liner water preheating system, comprising

[0007] A hybrid heating assembly, which is used to heat the oil-based medium by steam and electric heating, and comprises a box, a nozzle placed in the box, and a steam heating pipe;

[0008] A separation component is used to extract the medium in the box body and separate it, including a spiral centrifuge tube, which is separated into an inner ring cavity and an outer ring cavity by a partition net. Condensate passes through the partition net into the outer ring cavity due to centrifugal force, and the tension of each droplet is eliminated by the partition net to make the droplets converge. The oil-based medium in the inner ring cavity heats the cylinder liner preheated water through a heat exchanger, and then returns to the box body through a nozzle, and the mixture of the oil-based medium and condensate in the outer ring cavity returns to the bottom of the box body.

[0009] As a further optimization scheme of the present invention, the box body also has an electric heater, the nozzles are commonly connected to a liquid inlet pipe, and the nozzles are all facing the electric heater. The nozzles spray the oil-based medium to form droplets, the steam passes through the oil-based medium and is discharged, and the oil-based medium is sprayed onto the electric heater for further heating.

[0010] As a further optimization scheme of the present invention, the steam heating pipe is supplied with steam by a boiler, and the steam heating pipe enters the box body from the bottom of the box body, and the formed steam moves upward to heat the oil-based medium sprayed from the nozzle.

[0011] As a further optimization scheme of the present invention, the inner annular cavity is connected to the heat exchanger through a first medium pipe, and the outer annular cavity is connected to the casing through a second medium pipe. The medium pipes are driven by a first medium pump. The oil-based medium separated by centrifugation enters the heat exchanger, and the mixture of water and oil-based medium separated by centrifugal force returns to the casing and is stratified by density difference. The water can be discharged after sinking, and the oil-based medium continues to be sucked into the separation component after floating.

[0012] As a further optimization scheme of the present invention, the box is connected to the centrifugal tube through a discharge pipe, the height of the steam heating tube is higher than the discharge pipe, and the height of the discharge pipe is higher than the second medium tube. During the heat exchange process between the oil-based medium and the steam, the steam may condense into droplets and gather at the bottom of the box to form a water layer, and the height of the discharge pipe is higher than the water layer, so that most of the medium entering the separation component is oil-based medium, and the water droplets that are mixed and not separated are separated by the separation component. After separation, the mixture of oil-based medium and water droplets in the outer ring cavity returns to the bottom of the box, and the oil-based medium floats.

[0013] As a further optimization scheme of the present invention, the heat exchanger is a shell-and-tube heat exchanger, and its heat exchange end is connected in parallel to the water cooling pipeline of the diesel engine through a three-way valve. Since the diesel engine cylinder liner itself has a water cooling pipeline, it can be used for preheating before the water cooling pipeline is operated. The on-off is controlled by the three-way valve. Before the diesel engine is operated, the water cooling pipeline is closed, and the part of the water cooling pipeline entering the diesel engine cylinder liner is preheated. During the operation of the diesel engine, when the cylinder liner needs to be cooled, the preheating pipeline is closed and conventional cooling is performed through the water cooling pipeline.

[0014] As a further optimization scheme of the present invention, the inner annular cavity and the oil-based medium pipeline of the heat exchanger are connected in parallel with a cleaning component, which is used to clean the condensed scale in the oil-based medium heat exchange pipeline through cleaning balls and blocks arranged on the surface of the cleaning balls. The overall density of the cleaning balls is lower than that of the oil-based medium. Although most of the impurities carried in the steam are stored in water droplets or water layers, the oil-based medium may also carry a small amount of impurities during the interaction between the water droplets. Although the impurity content is low and the condensation is slow, the heat exchange channel of the heat exchanger itself is relatively dispersed and narrow, and its long-term condensation still affects the heat exchange efficiency. Therefore, this scheme performs regular maintenance on the heat exchanger through the cleaning component.

[0015] As a further optimization scheme of the present invention, the cleaning assembly includes a tank body, an ejection pipe extending from the bottom end of the tank body and provided with a second medium pump, a venturi tube provided between the ejection pipe and the heat exchanger, and a return pipe provided at the other end of the heat exchanger, wherein the negative pressure end of the venturi tube is connected to the upper end of the tank body through a suction pipe. This scheme performs cleaning by arranging cleaning balls and inserts. When the cleaning balls flow into the heat exchanger, they are ground and impacted by the inserts to eliminate scaling. Since the cleaning balls cannot pass through the impeller of the second medium pump, this scheme arranges a venturi tube to form a negative pressure effect to suck the cleaning balls into the circulating cleaning flow channel.

[0016] As a further optimization solution of the present invention, baffles are provided at both ends of the oil-based medium pipeline of the heat exchanger to prevent the cleaning ball from entering the liquid inlet pipe or the first medium pipe.

[0017] As a further optimization scheme of the present invention, the ejection pipe is slidingly provided with a truncated cone-shaped nozzle, wherein the nozzle is kept retracted by a spring and is kept extended when the ejection pipe has pressure, wherein the nozzle blocks the narrow channel of the venturi tube when it is extended to the maximum stroke to close the suction pipe. During cleaning, since the ejection pipe outlet is small, the pressure generated pushes the ejection pipe forward, but at this time it does not block the narrow channel of the venturi tube. The suction pipe has a negative pressure and sucks the cleaning ball from the tank body. After cleaning is completed, in order to return the cleaning ball to the tank body, the pressure is increased by the second medium pump to extend the nozzle to the maximum extent, blocking the above-mentioned narrow channel and preventing the cleaning ball from entering the venturi tube again, so that all the cleaning balls in the heat exchanger are flushed back into the tank body.

[0018] The beneficial effects of the present invention are:

[0019] The present invention adopts an oil-based medium sprayed into droplets for interactive heating with steam, and the steam is condensed into water and then separated from the oil-based medium. The oil-based medium and the water droplets are connected to a heat exchanger after centrifugal separation, and the heat exchanger is connected in parallel to the water cooling pipeline of the diesel engine cylinder liner. The coolant in the water cooling pipeline is heated by heat exchange, thereby preventing impurities formed by steam from scaling in the heat exchanger and reducing the heat exchange effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a cross-sectional view of the box and tank structure of the present invention;

[0022] Figure 3 The present invention Figure 2 A magnified view of the structure of part A;

[0023] Figure 4 is a top cross-sectional view of a centrifuge tube of the present invention;

[0024] Figure 5 The present invention Figure 3 A magnified view of the structure of part B;

[0025] Figure 6 It is a schematic diagram of a cleaning ball of the present invention;

[0026] Figure 7 It is a schematic diagram of the heat exchanger and the diesel engine water cooling circuit of the present invention;

[0027] In the figure: 1. mixing heating component; 11. box body; 12. nozzle; 13. electric heater; 14. steam heating pipe; 15. discharge pipe; 16. liquid inlet pipe; 2. separation component; 21. centrifugal tube; 22. separation net; 23. inner ring cavity; 24. outer ring cavity; 25. first medium pipe; 26. second medium pipe; 27. first medium pump; 3. heat exchanger; 31. three-way valve; 4. cleaning component; 41. tank body; 42. reflux pipe; 43. second medium pump; 44. venturi tube; 45. suction pipe; 46. baffle; 47. ejection pipe; 48. spring; 49. nozzle; 5. boiler; 6. cleaning ball; 61. insert; 7. diesel engine; 8. water cooling pipeline. DETAILED DESCRIPTION

[0028] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0029] Example 1

[0030] like Figure 1-7 As shown, a diesel engine cylinder liner water preheating system includes

[0031] A hybrid heating assembly 1, which is used to heat the oil-based medium by steam and electric heating, comprises a box 11, a nozzle 12 disposed in the box 11, and a steam heating pipe 14;

[0032] The separation component 2 is used to extract the medium in the box body 11 and separate it, including a spiral centrifuge tube 21. The centrifuge tube 21 is separated into an inner ring cavity 23 and an outer ring cavity 24 by a partition net 22. The condensed water passes through the partition net 22 and enters the outer ring cavity 24 due to centrifugal force, and the tension of each droplet is eliminated by the partition net 22 to make the droplets converge, so that the small independent droplets can converge into a water flow, wherein the oil-based medium in the inner ring cavity 23 heats the cylinder liner preheated water through the heat exchanger 3, and then returns to the box body 11 through the nozzle 12, and the mixture of the oil-based medium and condensed water in the outer ring cavity 24 returns to the bottom of the box body 11.

[0033] In this solution, an oil-based medium is sprayed into a droplet shape to perform interactive heating with steam. The steam is condensed into water and then separated from the oil-based medium. The oil-based medium and the water droplets are centrifugally separated and then connected to a heat exchanger 3. The heat exchanger 3 is connected in parallel to the water cooling pipeline of the diesel engine 7 cylinder liner. The coolant in the water cooling pipeline is heated by heat exchange, thereby preventing impurities formed by steam from scaling in the heat exchanger 3 and reducing the heat exchange effect.

[0034] It should be noted that, especially for marine diesel engines, the water used in its boiler contains more impurities, and a large number of droplets are entrained in the saturated steam. The droplets are easy to carry impurities and condense scale. Since the scale condenses in the heat exchanger and is difficult to clean, the oil-based medium and steam are interactively heated, which not only increases the heating efficiency, but also condenses into droplets and the entrained dirt sinks to the bottom of the oil-based medium to form a water layer, which is discharged after accumulating to a certain height. Although the oil-based medium interacts with the steam, the oil-based medium and water are not miscible with each other, and fewer impurities enter the oil-based medium. Therefore, the service life and heat exchange efficiency of the heat exchanger are greatly improved, and the oil-based medium can use synthetic hydrocarbon oil with a density lower than water.

[0035] The box 11 also has an electric heater 13, and the nozzles 12 are connected to a liquid inlet pipe 16, and the nozzles 12 are all facing the electric heater 13. The nozzles 12 spray the oil-based medium to form droplets, and the steam is discharged after passing through the oil-based medium, while the oil-based medium is sprayed onto the electric heater 13 for further heating.

[0036] The steam heating pipe 14 is supplied with steam by the boiler 5 , and the steam heating pipe 14 enters the box body 11 from the bottom of the box body 11 , and the formed steam moves upward to heat the oil-based medium sprayed from the nozzle 12 .

[0037] The inner annular cavity 23 is connected to the heat exchanger 3 through the first medium pipe 25, and the outer annular cavity 24 is connected to the housing 11 through the second medium pipe 26. The medium pipes are driven by the first medium pump 27. A baffle is provided at one end of the separation net 22 close to the first medium pipe 25 and the second medium pipe 26 to achieve a complete separation, so that each medium can enter the corresponding medium pipe 25. The oil-based medium separated by centrifugation enters the heat exchanger 3, and the mixture of water and oil-based medium separated by centrifugal force returns to the housing 11 and is stratified by density difference. The water can be discharged after sinking, and the oil-based medium continues to be sucked into the separation component 2 after floating.

[0038] The housing 11 is connected to the centrifugal tube 21 through the discharge pipe 15. The height of the steam heating tube 14 is higher than the discharge pipe 15. The height of the discharge pipe 15 is higher than the second medium pipe 26. During the heat exchange between the oil-based medium and the steam, the steam may condense into droplets and gather at the bottom of the housing 11 to form a water layer. The height of the discharge pipe 15 is higher than the water layer, so that most of the medium entering the separation component 2 is oil-based medium, and the water droplets that have not been separated are separated by the separation component 2. After separation, the mixture of oil-based medium and water droplets in the outer ring cavity 24 returns to the bottom of the housing 11, and the oil-based medium floats.

[0039] The heat exchanger 3 is a shell-and-tube heat exchanger, and its heat exchange end is connected in parallel to the water cooling pipeline 8 of the diesel engine 7 through a three-way valve 31, including a straight pipeline and a baffle channel. The straight pipeline is used to circulate the oil-based medium, and the baffle channel is used to heat the water flowing through the water cooling pipeline 8. Since the cylinder liner of the diesel engine 7 itself has a water cooling pipeline 8, it can be used for preheating before the water cooling pipeline 8 is operated. The on-off is controlled by the three-way valve 31. Before the diesel engine 7 is operated, the water cooling pipeline 8 is closed, and the part of the water cooling pipeline 8 entering the cylinder liner of the diesel engine 7 is preheated. During the operation of the diesel engine 7, when the cylinder liner needs to be cooled, the preheating pipeline is closed and conventional cooling is performed through the water cooling pipeline 8.

[0040] In the inner annular cavity 23, a cleaning component 4 is connected in parallel in the pipeline of the oil-based medium of the heat exchanger 3, which is used to clean the condensed scale in the oil-based medium heat exchange pipeline through the cleaning ball 6 and the insert 61 arranged on the surface of the cleaning ball 6. The overall density of the cleaning ball 6 is lower than that of the oil-based medium. Although most of the impurities carried in the steam are stored in the water droplets or water layers, the oil-based medium may also carry a small amount of impurities during the interaction between the water droplets. Although the impurity content is low and the condensation is slow, the heat exchange channel of the heat exchanger 3 itself is relatively dispersed and narrow, and its long-term condensation still affects the heat exchange efficiency. Therefore, this scheme uses the cleaning component 4 to perform regular maintenance and cleaning on the heat exchanger.

[0041] The cleaning assembly 4 includes a tank body 41, an ejection pipe 47 extending from the bottom end of the tank body 41 and provided with a second medium pump 43, a venturi tube 44 provided between the ejection pipe 47 and the heat exchanger 3, and a reflux pipe 42 provided at the other end of the heat exchanger 3, wherein the negative pressure end of the venturi tube 44 is connected to the upper end of the tank body 41 through a suction pipe 45. This scheme performs cleaning by providing a cleaning ball 6 and an insert 61. When the cleaning ball 6 flows into the heat exchanger 2, it is ground and impacted against the pipe of the heat exchanger 2 by the insert 61 to eliminate scaling. Since the cleaning ball 61 cannot pass through the impeller of the second medium pump 26, this scheme provides a venturi tube 44 to form a negative pressure effect to suck the cleaning ball 6 into the circulating cleaning flow channel.

[0042] Specifically, Figure 2 , 3 As shown in FIGS. 5 and 6, the bottom of the tank body 41 is oil-based medium, and the upper layer is a floating cleaning ball 6. The second medium pump 43 sprays the oil-based medium from the ejection pipe 47, and enters the heat exchanger 3 after passing through the venturi tube 44. The negative pressure area formed by the venturi tube 44 sucks the cleaning ball 6 from the upper layer of the tank body 41 through the suction pipe 45. The cleaning ball 6 is flushed into the tube array of the heat exchanger 3, cleaned by impact and grinding, and then returned to the tank body 41. Sediment collection can be set in the tank body 41, which will not be described here. A retaining net 46 is set at both ends of the oil-based medium pipeline of the heat exchanger to prevent the cleaning ball 6 from entering the liquid inlet pipe 16 or the first medium pipe 25.

[0043] The ejection pipe 47 is slidably provided with a truncated cone-shaped ejection pipe 49, wherein the ejection pipe 49 is kept retracted by a spring 48 and is kept extended when the ejection pipe 47 has pressure, wherein the ejection pipe 49 blocks the narrow passage of the venturi tube 44 when it is extended to the maximum stroke to close the suction pipe 45. During cleaning, since the ejection pipe 47 has a small outlet, the pressure generated pushes the ejection pipe 47 forward, but at this time it does not block the narrow passage of the venturi tube 44, and the suction pipe 45 has a negative pressure to suck the cleaning ball 6 from the tank body. After cleaning, in order to return the cleaning ball 6 to the tank body 41, the pressure is increased by the second medium pump 27 to extend the ejection pipe 47 to the maximum extent, blocking the above-mentioned narrow passage, and no longer having a venturi effect, preventing the cleaning ball 6 from entering the venturi tube 44 again, so that the cleaning ball 6 in the heat exchanger 3 is completely flushed back to the tank body 41 through the reflux pipe 42.

[0044] The specific implementation method is as follows: the oil-based medium is mixed and heated by the steam from the boiler 5 and the electric heater 13 until the preheating is completed. In this process, the water condensed from the steam is deposited at the bottom of the box 11, and the oil-based medium enters the heat exchanger 3 after centrifugal separation to heat the water in the water cooling pipeline 8, and then enters the diesel engine 7 through the hot water to heat the cylinder liner.

[0045] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A diesel engine cylinder jacket water preheating system, characterized in that: include A mixed heating assembly (1) is used to heat an oil-based medium by steam and electric heating, comprising a box (11), a nozzle (12) disposed in the box (11), and a steam heating pipe (14); A separation component (2) is used to extract the medium in the housing (11) and separate it, comprising a spiral centrifuge tube (21). The centrifuge tube (21) is separated into an inner ring cavity (23) and an outer ring cavity (24) by a separation net (22). Condensate passes through the separation net (22) due to centrifugal force and enters the outer ring cavity (24). The tension of each droplet is eliminated by the separation net (22) so that the droplets converge. The oil-based medium in the inner ring cavity (23) heats the cylinder liner preheated water through the heat exchanger (3) and then returns to the housing (11) through the nozzle (12). The mixture of the oil-based medium and condensate in the outer ring cavity (24) returns to the bottom of the housing (11).

2. The diesel engine cylinder jacket water preheating system according to claim 1, characterized in that: The box body (11) also has an electric heater (13), and the nozzles (12) are commonly connected to a liquid inlet pipe (16), and the nozzles (12) are all facing the electric heater (13).

3. The diesel engine liner water preheating system according to claim 1, characterized in that: The steam heating pipe (14) is supplied with steam from the boiler (5), and the steam heating pipe (14) enters the box body (11) from the bottom of the box body (11).

4. The diesel engine liner water preheating system according to claim 3, characterized in that: The inner ring cavity (23) is connected to the heat exchanger (3) through a first medium pipe (25), and the outer ring cavity (24) is connected to the inside of the housing (11) through a second medium pipe (26), and both medium pipes are driven by a first medium pump (27).

5. The diesel engine cylinder jacket water preheating system according to claim 4, characterized in that: The box body (11) is connected to the centrifugal tube (21) via a discharge pipe (15), the height of the steam heating pipe (14) is higher than the discharge pipe (15), and the height of the discharge pipe (15) is higher than the second medium pipe (26).

6. The diesel engine liner water preheating system according to claim 1, characterized in that: The heat exchanger (3) is a shell-and-tube heat exchanger, and its heat exchange end is connected in parallel to the water cooling pipeline (8) of the diesel engine (7) through a three-way valve (31).

7. The diesel engine liner water preheating system according to claim 1, characterized in that: The inner annular cavity (23) and the oil-based medium pipeline of the heat exchanger (3) are connected in parallel with a cleaning component (4), which is used to clean the condensed scale in the oil-based medium heat exchange pipeline through a cleaning ball (6) and an insert (61) arranged on the surface of the cleaning ball (6), and the overall density of the cleaning ball (6) is lower than that of the oil-based medium.

8. The diesel engine liner water preheating system according to claim 7, characterized in that: The cleaning assembly (4) comprises a tank body (41), an ejection pipe (47) extending from the bottom end of the tank body (41) and provided with a second medium pump (43), a venturi tube (44) arranged between the ejection pipe (47) and the heat exchanger (3), and a return pipe (42) arranged at the other end of the heat exchanger (3), wherein the negative pressure end of the venturi tube (44) is connected to the upper end of the tank body (41) via a suction pipe (45).

9. The diesel engine liner water preheating system according to claim 7, characterized in that: Blocking nets (46) are provided at both ends of the oil-based medium pipeline of the heat exchanger to prevent the cleaning ball (6) from entering the liquid inlet pipe (16) or the first medium pipe (25).

10. The diesel engine liner water preheating system according to claim 8, characterized in that: The ejection pipe (47) is slidably provided with a truncated cone-shaped nozzle (49), wherein the nozzle (49) is kept retracted by a spring (48) and is kept extended when the ejection pipe (47) is under pressure, wherein the nozzle (49) blocks the narrow passage of the venturi tube (44) when extended to the maximum stroke to close the suction pipe (45).

Images