Quenching medium air cooling device for enabling quenched workpiece to obtain ideal mechanical performance

Abstract

The utility model discloses a quenching medium air cooling device and a quenching medium air cooling method which enable a quenched workpiece to obtain ideal mechanical performance, in the air cooling device, heat in a quenching medium is transmitted through a heat pipe bundle, and the flow speed of the quenching medium is controlled through a quenching liquid circulating pump, so that the flow speed, the pressure and the flow rate of the quenching medium are accurately regulated and controlled; the temperature of a quenching medium can be controlled within the optimal temperature range, ferrite phase change of a quenched part is effectively inhibited, the phase change temperature can be reduced, nucleation power can be increased, the effective grain size can be decreased, and the strength and low-temperature toughness of the steel part can be remarkably improved. Meanwhile, waste heat released during quenching medium cooling is recycled, the heat treatment energy consumption index can reach 280 kWh / ton or below, and the heat treatment energy consumption in China at present is 600 kWh / ton on average.

Description

Technical Field

[0001] The utility model relates to the industrial fields of metal heat treatment, metallurgy, forging, etc., and in particular to the cooling of various quenching media (including quenching oil, salt water, various quenching liquids), and the recovery of waste heat released during the cooling of the quenching media. Background Art

[0002] In the industrial fields of metal heat treatment, metallurgy, forging, etc., in order to obtain ideal mechanical properties, metal materials need to be quenched.

[0003] Traditional quenching medium heat exchangers, such as cooling quenching oil, use plate heat exchangers (oil-water heat exchange) for heat exchange. This cooling system has the following disadvantages:

[0004] (1) Through oil-water heat exchange, the heat released by the quenching oil is absorbed by the cooling water and cannot be used. It is discharged into the surrounding environment, forming a source of thermal pollution;

[0005] (2) The FRP cooling tower is used as a heat dissipation device, but the cooling effect is poor, making the quenching process difficult to implement; in winter in northern my country, the water splashing from the FRP cooling tower will cause ice to form, making the equipment unable to work normally and affecting the heat treatment process;

[0006] (3) Using a cooling quenching liquid pool as a heat dissipation device, spraying or natural cooling, whether the pool is placed on the ground or underground, it occupies a large area and it is difficult to avoid the cooling water being contaminated by dust. Once solid particles enter the pipeline, it will threaten the circulation of the cooling water channel and cause safety hazards to the operation of the equipment;

[0007] (4) When the ambient temperature is high in summer, a chiller is required to provide low-temperature cooling water;

[0008] (5) Evaporation consumes a lot of water, because no matter whether it is a cooling tower or a cooling pool, it is impossible to avoid the evaporation of water. In fact, they rely on the evaporation of water to a large extent to obtain cooling.

[0009] In addition, the surface of the traditional heat exchanger is relatively clean at the beginning and the cooling effect is good, but after a period of time, due to reasons such as dirt on the surface of the heat exchanger, the cooling capacity is greatly reduced, and the temperature of the quenching medium fluctuates greatly, seriously affecting the structure and performance of the quenched workpiece; the biggest hidden danger is that once the metal wall of the oil-water heat exchanger corrodes and leaks somewhere, it will cause the mixing of cold and hot fluids, and there is a risk of explosion.

[0010] These existing quenching solutions cannot accurately control the temperature of the quenching medium, especially after the equipment has been running for a period of time, its ability to control the temperature of the quenching medium has significantly decreased, and the quenching effect is directly related to the quenching medium temperature. In order to obtain ideal mechanical properties, how to accurately control the quenching medium temperature has become the main task that needs to be studied. At the same time, taking into account environmental protection and energy saving, it is necessary to develop new processes and equipment. Existing equipment cannot meet the requirements of this working condition.

[0011] Due to the above reasons, the inventors have modified the existing quenching temperature control technology in the hope of designing an air cooling device and air cooling method for the quenching medium that can solve the above problems. Utility Model Content

[0012] In order to overcome the above problems, the inventors have conducted intensive research and designed a quenching medium air cooling device and method that enables the quenched workpiece to obtain ideal mechanical properties. The air cooling device conducts the heat in the quenching medium through a heat pipe bundle and controls the flow rate of the quenching medium through a quenching liquid circulation pump, thereby accurately regulating the flow rate, pressure, and flow rate of the quenching medium. The air cooling device can control the quenching medium temperature within the optimal temperature range, effectively inhibit the ferrite phase transformation of the quenched part, reduce the phase transformation temperature, increase the nucleation force, and reduce the effective grain size, which can significantly improve the strength and low-temperature toughness of the steel part. At the same time, the waste heat released during the cooling of the quenching medium is recovered, so that the heat treatment energy consumption index can reach less than 280kWh / ton of workpiece, thereby completing the utility model.

[0013] Specifically, the purpose of the utility model is to provide a quenching medium air cooling device that enables the quenched workpiece to obtain ideal mechanical properties. The air cooling device includes an air cooler housing 5, an axial flow fan 6 and a fin-tube heat pipe assembly 16, wherein:

[0014] The fin-tube heat pipe assembly 16 is provided with a plurality of fin-tube heat pipe assemblies 16, which are arranged in staggered rows; the lower section of the heat pipe assembly 16 extends into the quenching medium, and the upper section of the heat pipe assembly 16 extends into the air cooler housing 17;

[0015] The heat of the quenching medium is transferred to the air cooler housing 17 through the fin-tube heat pipe assembly 16;

[0016] The air cooling device also includes a quenching liquid circulation pump 9 and a circulation pipeline 8, so that the external quenching medium continuously flows through the gap between the lower section of the fin-tube heat pipe assembly 16 and the U-shaped sleeve through the liquid inlet 3, and then is discharged through the liquid outlet 4;

[0017] The liquid inlet 3 and the liquid outlet 4 are both connected to the quenching device, so that the quenching medium in the quenching device is maintained at a preset temperature.

[0018] A ventilation grille 2 is provided on the air cooler housing 5, and outside air enters the air cooler housing 5 through the ventilation grille 2, is heated by the fin-tube heat pipe assembly 16, and is discharged from the air cooler housing 5 through the axial flow fan 6 and reused as an air heat source.

[0019] Among them, a control dial 7 is arranged in the square of the air cooling device, and the control dial 7 is connected to the signal of the quenching liquid circulation pump 9. The power of the quenching liquid circulation pump 9 is controlled by the control dial 7, and then the flow in the circulation pipeline 8 is controlled to achieve the purpose of controlling the temperature of the quenching medium in the quenching device.

[0020] The fin heat pipe assembly 16 is provided with a transversely arranged partition 15 , and the vertically arranged heat pipe assembly 16 is fixedly installed by the partition 15 , and the partition 15 separates the heat pipe assembly 16 into an upper section and a lower section.

[0021] The gap between the U-shaped sleeve 14 and the heat pipe assembly 16 of the air cooling device flows the quenching medium, and communicates with the liquid storage tank 1 below. The liquid storage tank 1 is filled with the quenching medium, and a liquid inlet 3 connected to the quenching device is provided on the liquid storage tank 1;

[0022] Under the action of the quenching liquid circulation pump 9 and the circulation pipeline 8, the quenching medium enters the liquid storage tank 1 from the quenching device through the liquid inlet 3, is discharged from the liquid outlet 4 after fully contacting and exchanging heat with the lower section of the heat pipe assembly 16, and enters the quenching device again.

[0023] The fin-tube heat pipe assembly 16 is divided into an upper section and a lower section by a partition 15, the U-shaped sleeve 14 is located below the partition 15, and the lower section of the heat pipe assembly 16 extends into the U-shaped sleeve;

[0024] The two ends of the U-shaped sleeve 14 are opened upward, and a heat pipe assembly is inserted into each of the two ends;

[0025] The U-shaped sleeve 14 is provided with a quenching liquid inlet 19 connected to the liquid storage tank 1, and the U-shaped sleeve 14 is also connected to the liquid outlet 4.

[0026] The gap between the lower section of the U-shaped sleeve 14 and the U-shaped sleeve is filled with quenching medium.

[0027] Under the action of the quenching liquid circulation pump 9 and the circulation pipeline 8, the quenching medium in the liquid storage tank 1 enters the U-shaped sleeve 14 through the quenching liquid inlet 19, and is discharged through the liquid outlet 4 after sufficient heat exchange between the U-shaped sleeve 14 and the heat pipe assembly 16.

[0028] Wherein, a heat transfer fin 20 is arranged on the outer side of the upper section of the heat pipe assembly 16;

[0029] A spiral groove 21 is formed on the inner wall surface of the heat pipe assembly 16 .

[0030] The heated air discharged from the air cooler housing 5 through the axial flow fan 6 is connected to a heating system or a drying system for heating in winter or drying materials, thereby realizing the reuse of heat energy.

[0031] The beneficial effects of the utility model include:

[0032] (1) The utility model provides an air-cooling device for a quenching medium that enables a quenched workpiece to obtain ideal mechanical properties. The air-cooling device can accurately control the flow rate, pressure, and flow rate of the quenching medium, and can control the temperature of the quenching medium within an optimal temperature range, thereby effectively controlling the ferrite phase transformation of the quenched workpiece, lowering the phase transformation temperature, increasing the nucleation force, and reducing the effective grain size, thereby significantly improving the strength and low-temperature toughness of the steel workpiece.

[0033] (2) The quenching medium air cooling device provided by the utility model can enable the quenched workpiece to obtain ideal mechanical properties, and can recover the waste heat released during the cooling of the quenching medium, so that the heat treatment energy consumption index can reach less than 280kWh / ton of workpiece. The current domestic average heat treatment energy consumption is 600kWh / ton.

[0034] (3) The utility model provides an air-cooling device for a quenching medium that enables a quenched workpiece to obtain ideal mechanical properties. The device has the advantages of simple and compact structure, small footprint, high thermal efficiency, energy and water saving, and low fluid resistance loss. Compared with the oil-water heat exchanger on the market, the weight of the overall device of the present application is only 1 / 3 to 1 / 2 of the shell-and-tube heat exchanger on the market, and the external dimensions are only 1 / 2 to 2 / 3 of the shell-and-tube heat exchanger. If several heat pipes are damaged during the operation of the air-cooling device of the present application, it will not affect the circulation of the cooling medium in the overall device of the present application, and there is no need to stop the device for inspection and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram showing the horizontal structure of a quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece;

[0036] Figure 2 A schematic diagram of the vertical structure of a quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece;

[0037] Figure 3 A schematic diagram showing the structure of a heat pipe air cooler of a quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece;

[0038] Figure 4 A schematic diagram of the heat pipe structure of a fin-in-tube heat pipe assembly of a quenching medium air cooling device for enabling a quenched workpiece to obtain ideal mechanical properties.

[0039] Reference numerals

[0040] 1-Liquid reservoir

[0041] 2-Ventilation grille

[0042] 3-Liquid inlet

[0043] 4-Liquid outlet

[0044] 5-Air cooler housing

[0045] 6-Axial flow fan

[0046] 7-Control dial

[0047] 8-Circulation pipeline

[0048] 9-Quenching liquid circulation pump

[0049] 10-Air cooling device base

[0050] 11-Vertical air cooling device frame

[0051] 12-Exhaust valve

[0052] 13- Lug

[0053] 14-U-type casing

[0054] 15-Partition

[0055] 16-Fin-tube heat pipe assembly

[0056] 17-Heat pipe air cooler frame

[0057] 18-Heat pipe fluid

[0058] 19-Quenching liquid inlet

[0059] 20-Spiral fin

[0060] 21- Groove on the inner wall of heat pipe

[0061] 22-Steel pipe DETAILED DESCRIPTION

[0062] The present invention is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present invention will become clearer and more specific.

[0063] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0064] The cooling of the quenching medium is a key process that determines whether the workpiece can be hardened and whether quenching defects can be generated. When the workpiece is required to obtain martensite without causing too much deformation during quenching, it is necessary to require the workpiece to be cooled quickly within the range of 400-650°C. Based on this, the quenching medium needs to be continuously controlled within this temperature range.

[0065] The utility model provides a quenching medium air cooling device which enables the quenched workpiece to obtain ideal mechanical properties, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown in , the air cooling device mainly includes: a liquid storage tank 1, an air cooler shell 5, an axial flow fan 6, a circulation pipeline 8, a quenching liquid circulation pump 9, and a fin-tube heat pipe assembly 16.

[0066] The liquid storage tank 1 is filled with quenching medium, and the liquid storage tank 1 is sealed in the air cooling device and is only connected to the outside through the circulation pipeline 8; the quenching medium in the present application is preferably industrial quenching oil;

[0067] The fin-tube heat pipe assembly 16 is provided with a plurality of fin-tube heat pipe assemblies 16, which are arranged in staggered rows; the lower section of the heat pipe assembly 16 extends into the quenching medium, and the upper section of the heat pipe assembly 16 extends into the air cooler housing;

[0068] The heat of the quenching medium is transferred to the air cooler housing 17 through the fin-tube heat pipe assembly 16, and the heat is then reused;

[0069] The air cooling device also includes a quenching liquid circulation pump 9 and a circulation pipeline 8, so that the external quenching medium flows continuously through the outer side of the lower section of the fin-tube heat pipe assembly 16 through the liquid inlet 3, especially the gap between the lower section and the U-shaped sleeve, and then discharged through the liquid outlet 4;

[0070] The liquid inlet 3 and the liquid outlet 4 are both connected to the quenching device, so that the quenching medium in the quenching device is maintained at a preset temperature.

[0071] For example, the preset quenching temperature range of water-based quenching liquid is 580~430℃.

[0072] The specific control parameters required to control the temperature of the quenching medium at the preset value are: flow rate 0.5~1m / s, flow rate 25~45m 3 / h, pressure 3.2~6.8bar.

[0073] Preferably, if Figure 1As shown in the figure, an axial flow fan 6 and a ventilation grille 2 are provided in the air cooler housing 5. External air enters the air cooler housing 5 through the ventilation grille 2, absorbs heat from the heat pipes of the finned sleeve heat pipe assembly 16, and is then discharged through the axial flow fan 6. The air is the heated air.

[0074] The heated air discharged from the air cooler housing 5 by the axial flow fan 6 is connected to the heating system or the drying system for heating in winter or drying materials, realizing the reuse of heat energy. The heated air heat is used for workshop heating or hot air drying of materials, which is an important technical approach to achieve energy conservation and emission reduction, and has broad development and application prospects.

[0075] A control dial 7 is provided on the front of the air cooling device, through which the flow of the quenching liquid circulation pump 9 is controlled to achieve the purpose of controlling the temperature of the quenching medium in the quenching device. The quenching quality of the parts is related to their final mechanical properties and service life. In this application, by accurately controlling the quenching temperature, the ferrite phase transformation of the quenched parts can be effectively controlled, the phase transformation temperature can be reduced, the nucleation force can be increased, and the effective grain size can be reduced, which can significantly improve the strength and low-temperature toughness of the steel parts, so that the quenched workpieces can obtain ideal mechanical properties.

[0076] Furthermore, in the present application, by controlling the quenching temperature, a large number of dislocation substructures can be present inside the martensite structure of the quenched workpiece, wherein the movable dislocations can alleviate local stress concentration and reduce the possibility of microcrack formation, thereby enabling the material to obtain a larger uniform plastic deformation. The dislocation refers to an internal microscopic defect of a crystalline material, where atoms are arranged irregularly locally, and is the boundary between the slipped part and the unslipped part in the crystal, and its existence has a great influence on the mechanical properties of the material.

[0077] Preferably, the fin-tube heat pipe assembly 16 is divided into an upper section and a lower section by a partition 15. The upper section heat pipe assembly constitutes a fin-tube structure, and the lower section heat pipe assembly is located in a U-shaped sleeve 14. The partition 15 divides the heat pipe assembly into two parts for cold and hot heat exchange.

[0078] In this application, the shell of the heat pipe assembly is a steel pipe 22, the material of which is 19 # Cold drawn seamless steel pipe, the heat pipe assembly is a fully enclosed vacuum tube with a vacuum degree of 2×10 -4 Pa, which contains a working fluid, which is water-ethanol, and has extremely high thermal conductivity and good isothermal properties. In a vacuum state, heat is transferred by evaporation and condensation of the working fluid. The heating section absorbs the heat of the hot fluid and transfers the heat to the working medium in the tube. After absorbing heat, the working fluid is transformed into steam in the form of evaporation and boiling. The steam rises to the upper section of the heat pipe assembly due to the pressure difference to release heat, and condenses into liquid to release latent heat of vaporization. The heat is transferred to the air cold fluid, that is, the air flow provided by the axial flow fan 6.

[0079] Preferably, a sleeve 14 is provided on the outer side of the lower heat pipe, and the sleeve 14 is a U-shaped sleeve.

[0080] Preferably, a liquid inlet 3 connected to a quenching device is provided on the liquid storage tank 1;

[0081] Under the action of the quenching liquid circulation pump 9 and the circulation pipeline 8, the quenching medium enters the liquid storage tank 1 from the quenching device through the liquid inlet 3, is discharged from the liquid outlet 4 after fully contacting and exchanging heat with the lower section of the heat pipe assembly 16, and enters the quenching device again.

[0082] Preferably, the fin-tube heat pipe assembly 16 further comprises a U-shaped tube 14 disposed below the partition 15, and the lower section of the heat pipe assembly 16 extends into the U-shaped tube;

[0083] The sleeve 14 is a U-shaped tube, with both ends of the U-shaped sleeve 14 opening upward, and a heat pipe group element 16 extending into each of the two ends;

[0084] The U-shaped sleeve 14 is provided with a quenching liquid inlet 19 connected to the liquid storage tank 1, and the U-shaped sleeve 14 is also connected to the liquid outlet 4.

[0085] The gap between the U-shaped sleeve 14 and the heat pipe assembly is filled with quenching medium.

[0086] Under the action of the quenching liquid circulation pump 9 connected to the circulation pipeline 8, the quenching medium in the liquid storage tank 1 enters the U-shaped sleeve 14 through the quenching liquid inlet 19, and is discharged through the liquid outlet 4 after sufficient heat exchange between the U-shaped sleeve 14 and the heat pipe assembly 16.

[0087] The gap between the U-shaped sleeve and the heat pipe assembly is the quenching liquid flow channel, which is transported by the quenching liquid circulation pump 9. The gap between the U-shaped sleeve and the heat pipe assembly is controlled between 5 and 10 mm, which is the flow channel of the quenching liquid. In this application, the U-shaped sleeve can control the gap of the heat exchange flow channel to be relatively small, that is, 5 to 10 mm, which can improve the heat exchange efficiency and take away the heat in the quenching medium more quickly.

[0088] In the present application, the U-shaped sleeve and the partition do not contact each other, so that the quenching medium in the liquid storage tank 1 can flow fully, first pre-exchange heat at the periphery of the U-shaped sleeve, then enter the U-shaped sleeve through the quenching liquid inlet 19 for sufficient heat exchange, and then flow back to the quenching device after reaching the preset temperature.

[0089] Preferably, if Figure 4 As shown in the figure, heat transfer fins 20 are arranged on the outer side of the upper heat pipe assembly; the fins 20 are connected to the outer side of the pipe by high-frequency welding to increase the heat transfer area.

[0090] The inner wall surface of the heat pipe assembly is provided with a spiral groove 21, which can enhance the convective heat transfer of the fluid in the heat pipe assembly; specifically, the spiral groove pipe causes the fluid to generate a spiral motion in the heat pipe assembly and has a certain radial velocity, thereby effectively enhancing the convective heat transfer in the pipe and significantly improving the overall heat transfer coefficient.

[0091] Since the heat transfer fluids on both sides of the heat transfer tube of the air cooler are gas and liquid respectively, the heat transfer coefficients differ by 100 times. Since the heat transfer coefficient of the air section is much smaller than that of the water-based quenching liquid, the thermal resistance of the air section is much greater than that of the aqueous solution section, which limits the improvement of the heat transfer coefficient. In this application, fins are added to the air section to greatly reduce its convective heat transfer thermal resistance. After the fins are added, the heat transfer coefficient and heat transfer amount Q are greatly improved, which can meet the needs of synchronous heat transfer.

[0092] In the present application, the inner helix angle of the heat pipe assembly is preferably 35°, the pitch is 5mm, and the groove depth is 1.5mm. At the same time, the flow resistance is taken into consideration; the spiral grooved tube can enhance the heat exchange capacity and strengthen the heat exchange compared with the inner wall of the light tube. The structure is relatively simple, which is convenient for rapid mass processing and can reduce production costs.

[0093] Preferably, an air cooling device base 10 is provided at the bottom of the air cooling device.

[0094] An exhaust valve 12 and a lifting lug 13 are provided on the top of the air cooling device.

[0095] The quenching medium air cooling device in the present application that enables the quenched workpiece to obtain ideal mechanical properties can be set in various structural forms, such as Figure 1 The horizontal tube type shown in Figure 2 The vertical tube type shown in the figure. Various structural forms have their own characteristics and are specially designed according to different parameter requirements to meet the needs of different users.

[0096] In this application, if Figure 3 As shown, the heat pipe assembly is composed of a tube bundle, which is arranged in a staggered row. The spacing of the tube bundle is arranged according to the heat exchange amount and the resistance of the hot and cold sections. The heated quenching liquid flows through the gap between the lower part of the heat pipe assembly and the U-shaped sleeve. Figure 4 As shown, the heat pipe is a vacuum chamber filled with heat pipe working medium 18. When the heat outside the pipe is transferred to the inside of the pipe, the working medium 18 is phase-changed and evaporated, and the steam is quickly transferred to the upper part of the heat pipe, and is absorbed by the cold air outside the pipe through the pipe wall. After the working medium in the pipe is condensed, it flows back to the lower part of the heat pipe due to gravity, and thus the working medium 18 is continuously circulated for heat exchange, so that the quenching liquid is cooled to obtain the ideal quenching temperature.

[0097] In the present application, the lower U-shaped sleeve of the air cooling device and the lower section of the heat pipe assembly are provided with a quenching medium channel, and the upper section is provided with a cold air flow channel. The heat exchange process is as follows: the quenching medium between the lower section of the air cooling device, i.e. the sleeve and the heat pipe assembly, heats the working fluid in the heat pipe assembly under vacuum through the pipe wall, causing it to evaporate and flow to the upper part of the heat pipe assembly after phase change, and its heat is absorbed by the air flowing through the fin surface outside the pipe, taking away the heat. The heat of the working fluid in the heat pipe assembly is absorbed and condensed, and flows back to the lower part of the heat pipe assembly due to gravity, thus achieving heat exchange through a reciprocating cycle. The working fluid in the heat pipe assembly absorbs heat from the quenching medium, and after evaporation, the steam is condensed into liquid by the cold air outside the pipe. The heat pipe has a heat exchange capacity with extremely high heat transfer performance. It is completed through two opposite phase change processes of boiling and condensation of the working fluid under vacuum. The heat transfer coefficient of the heat pipe assembly is more than 10 times that of the shell-and-tube heat exchanger.

[0098] Historically, the cooling of quenching oil in heat treatment has only focused on the cooling performance of quenching oil, without considering the reuse of the heat released by quenching oil. At present, the average energy consumption index of heat treatment in my country is 600kWh / ton of workpiece. After applying the quenching medium air cooling device that enables the quenched workpiece to obtain ideal mechanical properties, the heat treatment energy consumption index can be reduced to less than 280kWh / ton of workpiece, while the world's advanced energy consumption index is 400kWh / ton of workpiece. The recycled heated hot air can be used in production and life. The solution in this application is a breakthrough in energy utilization in the heat treatment industry, and has a guiding and exemplary role in energy conservation and emission reduction.

[0099] The utility model also provides a method for air cooling of a quenching medium to enable a quenched workpiece to obtain ideal mechanical properties, the method comprising the following steps:

[0100] Step 1, connecting the quenching medium to a quenching medium air cooling device that enables the quenched workpiece to obtain ideal mechanical properties;

[0101] Step 2, setting / controlling the air volume of the axial flow fan;

[0102] Step 3, regulating the opening of the throttle valve on the quenching liquid circulation pump 9, thereby controlling the flow in the circulation pipeline 8.

[0103] In step 2, an inlet stator blade (inlet guide vane) with an adjustable installation angle is provided at the inlet of the axial flow fan; the flow rate of the axial flow fan is regulated by changing the inlet stator blade angle to adjust the air flow rate during the operation of the fan; the axial flow fan can be a 190kW air cooler axial flow fan;

[0104] In step 3, a throttle valve is provided on the return line of the quenching liquid circulation pump 9; the flow rate in the circulation line 8 is regulated by adjusting the opening of the throttle valve on the return line of the quenching liquid circulation pump 9 to return part of the flow rate to the liquid inlet pipe, thereby changing the flow characteristics of the circulation line. The quenching liquid circulation flow rate of the quenching liquid circulation pump can reach 50m 3 / h, pressure 1.38bar.

[0105] In step 3 of the present application, the quenching medium in the quenching device is extracted by the quenching liquid circulation pump 9, enters the liquid storage tank 1 through the liquid inlet 3, and then enters the gap between the U-shaped sleeve 14 and the heat pipe assembly through the quenching liquid inlet 19. After the U-shaped sleeve 14 and the heat assembly 16 have fully exchanged heat, it is discharged through the liquid outlet 4 and flows back into the quenching device. In this process, the flow rate of the quenching liquid circulation pump 9 is controlled by the control dial 7, so as to control the cooling effect of the air cooling device on the quenching medium; when the temperature of the workpiece in the quenching device is reduced to between 650 and 400°C, it is necessary to increase the flow rate of the quenching liquid circulation pump 9 to further reduce the problem of the quenching medium, so that the workpiece is quickly cooled to avoid pearlite or Bayesian transformation through the most unstable region of supercooled Austenite. At this time, it is also necessary to adjust the inlet stator of the axial flow fan so that the air volume of the axial flow fan reaches the maximum value of 24000m 3 / h, static pressure 60Pa; at the same time, the throttle valve on the quenching liquid circulation pump return pipe is opened to the maximum, and the flow rate reaches 50m 3 / h. At this time, the metallographic structure of the quenched workpiece is a lath-like Martensite structure.

[0106] Preferably, the operation of the equipment in the present application can be automatically controlled, and the operating parameters are connected with the DCS (data acquisition, management, storage, and upload) system for real-time online monitoring.

[0107] Example 1

[0108] When quenching a gear workpiece, the quenching medium is cooled by a quenching medium air cooling device that enables the quenched workpiece to obtain ideal mechanical properties:

[0109] The quenching medium air cooling device for enabling the quenched workpiece to obtain ideal mechanical properties comprises:

[0110] An air cooler housing 5, an axial flow fan 6 and a fin-tube heat pipe assembly 16, wherein a plurality of fin-tube heat pipe assemblies are provided and arranged in parallel with each other; the lower section of the heat pipe assembly 16 extends into the U-shaped sleeve 14, the gap between the heat pipe assembly 16 and the U-shaped sleeve 14 is 8 mm, and the gap between the U-shaped sleeve 15 and the lower section of the heat pipe assembly is filled with a quenching medium, and the upper section of the heat pipe assembly 16 extends into the air cooler housing 17;

[0111] The air cooling device further comprises a liquid storage tank 1 arranged below the air cooler housing 17, the liquid storage tank 1 is filled with quenching medium, and a liquid inlet 3 connected to the quenching device is arranged on the liquid storage tank 1;

[0112] The two ends of the U-shaped sleeve 14 are open upwards, and a heat pipe element is inserted into each of the two ends;

[0113] The U-shaped sleeve 14 is provided with a quenching liquid inlet 19 connected to the liquid storage tank 1, and the U-shaped sleeve 14 is also connected to the liquid outlet 4.

[0114] Under the action of the quenching liquid circulation pump 9 and the circulation pipeline 8, the quenching medium in the liquid storage tank 1 enters the U-shaped sleeve 14 through the quenching liquid inlet 19, and is discharged through the liquid outlet 4 after sufficient heat exchange between the U-shaped sleeve 14 and the heat pipe assembly 16.

[0115] The working medium is arranged in the lower section of the heat pipe assembly 16, which can be vaporized after being subjected to heat transfer by the quenching medium, rise to the upper section of the heat pipe assembly, release heat through phase change, and liquefy again after heat exchange with the air flowing through the air cooler shell 5 through the spiral grooves and fins, and flow back to the lower section of the heat pipe assembly 16.

[0116] The heated air flowing through the air cooler housing 5 continues to flow under the control of the axial flow fan 6, and the heated air is connected to a heating system or a drying system for heating in winter or drying materials, thereby realizing the reuse of heat energy.

[0117] Main structural parameters:

[0118] Heat pipe assembly and fin materials: steel pipe, steel fin;

[0119] Steel pipe φ32×2mm, steel fin density 219 / m, fin height 12mm, fin thickness 0.8mm;

[0120] The length of the tube is 1.2m / root, 8 tubes are connected in parallel for one leg, a total of 2 legs;

[0121] Pipe row width: 0.72m.

[0122] The basic data obtained are as follows:

[0123] Quenching medium flow rate 19m 3 / h;

[0124] Quenching medium flow rate in circulation pipeline 8: 1.21 m / s;

[0125] The temperature at the liquid inlet 3 is 80°C, and the temperature at the liquid outlet 4 is 61°C;

[0126] Reynolds number inside the circulation pipeline 8; Re i =4880;

[0127] Maximum air velocity between pipes inside air cooler shell 5: 8.2m / s

[0128] Convection heat transfer coefficient in air cooler shell 5: 47.3W / (m 2 ℃)

[0129] Air inlet temperature of air cooler housing 5: 19°C;

[0130] Air outlet temperature of air cooler housing 5: 46°C;

[0131] Through specific work calculations, it can be known that the heat load of the quenching medium air cooling device that enables the quenched workpiece to obtain ideal mechanical properties is 177kW, which can fully cool the quenching medium required for quenching the gear workpiece. The economic benefits of the quenching medium air cooling device that enables the quenched workpiece to obtain ideal mechanical properties are further explained below.

[0132] The air-cooling medium is cooled by the air section of the heat pipe assembly, and the obtained hot air is recovered for workshop heating or hot air drying of materials.

[0133] 177kW air cooler heat dissipation power, can make the volume flow rate 3.7×10 4 m 3 / h of cold air temperature rises by 15℃, when the ambient temperature is 30℃, the supply air temperature reaches 46℃. 4 m 3 / h or more cold air is raised from 0℃ to 30℃ for heating offices and production workshops. Assuming the heating load per unit area is 190W / m 2 , the heating area can reach 935m 2 .

[0134] 177kW of heat is recovered from the quenching medium, which is equivalent to saving the same amount of steam heating heat, that is, the theoretical heat supply per day reaches

[0135] 177×24×3600=15156MJ

[0136] If the calorific value of raw coal is calculated as 5000 kcal / kg (19.9 MJ / kg), the amount of coal saved per day is 0.73 tons. Considering that the thermal efficiency of the heating boiler is 70%, the actual amount of coal saved per day is about 0.73 ÷ 0.7 = 1.1 tons. Based on 119 working days per year, the total amount of coal saved will be 132 tons.

[0137] The environmental pollution caused by burning 132 tons of raw coal - carbon and sulfur dioxide emissions will also be eliminated at the same time. The energy consumption and corresponding environmental pollution incurred during the mining and transportation of these 132 tons of coal must also be considered.

[0138] Example 2

[0139] A gear workpiece consistent with the situation in Example 1 is selected for quenching. For the same quenching medium, a quenching medium air cooling device that is basically the same as in Example 1 and enables the quenched workpiece to obtain ideal mechanical properties is used for cooling:

[0140] The quenching medium air cooling device for obtaining ideal mechanical properties of the quenched workpiece described in Example 2 is different from that in Example 1 in that: the gap size between the heat pipe assembly 16 and the U-shaped sleeve 14 is 6 mm;

[0141] The basic data obtained are as follows:

[0142] Quenching medium flow rate 19m 3 / h;

[0143] Quenching medium flow rate in circulation pipeline 8: 1.21 m / s;

[0144] The temperature at the liquid inlet 3 is 85°C, and the temperature at the liquid outlet 4 is 71°C;

[0145] Reynolds number inside the circulation pipeline 8; Re i =4880;

[0146] Maximum air velocity between pipes inside air cooler shell 5: 8.2m / s

[0147] Convection heat transfer coefficient in air cooler shell 5: 47.3W / (m 2 ℃)

[0148] Air inlet temperature of air cooler housing 5: 19°C;

[0149] Air outlet temperature of air cooler housing 5: 40°C;

[0150] Compared with Example 1, it can be seen that the gap size between the heat pipe assembly 16 and the U-shaped sleeve 14 in Example 2 is 6 mm, which causes the heat pipe assembly 16 to be unable to fully conduct the heat in the quenching medium to the air cooler shell 5, resulting in a decrease in the overall heat exchange performance, insufficient heat load, and a high quenching medium temperature, which affects the quenching effect.

[0151] Example 3

[0152] A gear workpiece consistent with the situation in Example 1 is selected for quenching. For the same quenching medium, a quenching medium air cooling device that is basically the same as in Example 1 and enables the quenched workpiece to obtain ideal mechanical properties is used for cooling:

[0153] The quenching medium air cooling device described in Example 2 for enabling the quenched workpiece to obtain ideal mechanical properties is different from that in Example 1 in that: a U-shaped sleeve 14 is not provided, and the quenching medium in the quenching device enters the liquid storage tank 1 through the liquid inlet 3, and after heat exchange with the lower section of the heat pipe assembly 16, flows back to the quenching device through the liquid outlet 4.

[0154] The basic data obtained are as follows:

[0155] Quenching medium flow rate 19m 3 / h;

[0156] Quenching medium flow rate in circulation pipeline 8: 1.21 m / s;

[0157] The temperature at the liquid inlet 3 is 92°C, and the temperature at the liquid outlet 4 is 84°C;

[0158] Reynolds number inside the circulation pipeline 8; Re i =4880;

[0159] Maximum air velocity between pipes inside air cooler shell 5: 8.2m / s

[0160] Convection heat transfer coefficient in air cooler shell 5: 47.3W / (m 2 ℃)

[0161] Air inlet temperature of air cooler housing 5: 19°C;

[0162] Air outlet temperature of air cooler housing 5: 30°C;

[0163] Compared with Example 1, it can be seen that in Example 3, the U-shaped sleeve 14 is not provided, resulting in a significant decrease in the heat conduction capacity of the heat pipe assembly 16 for the quenching medium, and a significant reduction in the heat source obtained in the air cooler shell 5, resulting in a low temperature of the heated air, which not only causes the quenching medium temperature to be high and the quenching effect to be reduced, but also causes the recovered heat energy to be too little and the temperature to be too low, making it difficult to effectively utilize.

[0164] The present invention has been described above in conjunction with preferred embodiments, but these embodiments are merely exemplary and serve only as illustrations.

[0165] On this basis, various replacements and improvements can be made to the present invention, all of which fall within the protection scope of the present invention.

Claims

1. A quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece, characterized in that: The air cooling device comprises an air cooler housing (5), an axial flow fan (6) and a fin-tube heat pipe assembly (16), wherein: The fin-tube heat pipe assembly (16) is provided with a plurality of fin-tube heat pipe assemblies (16) which are arranged in a staggered manner; the lower section of the heat pipe assembly (16) extends into the quenching medium, and the upper section of the heat pipe assembly (16) extends into the air cooler housing (5); The heat of the quenching medium is transferred to the air cooler housing (5) through the fin-tube heat pipe assembly (16); The air cooling device also includes a quenching liquid circulation pump (9) and a circulation pipeline (8), so that the external quenching medium flows continuously through the gap between the lower section of the fin-tube heat pipe assembly (16) and the U-shaped tube through the liquid inlet (3), and then is discharged through the liquid outlet (4); The liquid inlet (3) and the liquid outlet (4) are both connected to the quenching device, so that the quenching medium in the quenching device is maintained at a preset temperature.

2. The quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece according to claim 1, characterized in that: A ventilation grille (2) is provided on the air cooler housing (5), and outside air enters the air cooler housing (5) through the ventilation grille (2), is heated by the fin-tube heat pipe assembly (16), and is discharged from the air cooler housing (5) through the axial flow fan (6) and reused as an air heat source.

3. The quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece according to claim 1, characterized in that: A control dial (7) is arranged on the front of the air cooling device. The control dial (7) is connected to the signal of the quenching liquid circulation pump (9). The flow rate of the quenching liquid circulation pump (9) is controlled by the control dial (7), thereby controlling the flow rate in the circulation pipeline (8), thereby achieving the purpose of controlling the temperature of the quenching medium in the quenching device.

4. The quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece according to claim 1, characterized in that: The fin heat pipe assembly (16) is provided with a transversely arranged partition (15), and the vertically arranged heat pipe assembly (16) is fixedly installed via the partition (15), and the partition (15) divides the heat pipe assembly (16) into an upper section and a lower section.

5. The quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece according to claim 1, characterized in that: A quenching medium flows through the gap between the U-shaped sleeve (14) and the heat pipe assembly (16) of the air cooling device, and is communicated with a liquid storage tank (1) below. The liquid storage tank (1) is filled with the quenching medium, and a liquid inlet (3) connected to the quenching device is provided on the liquid storage tank (1); Under the action of the quenching liquid circulation pump (9) and the circulation pipeline (8), the quenching medium enters the liquid storage tank (1) from the quenching device through the liquid inlet (3), is fully contacted with the lower section of the heat pipe assembly (16) and heat is exchanged, and is discharged from the liquid outlet (4) and enters the quenching device again.

6. The quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece according to claim 5, characterized in that: The fin-tube heat pipe assembly (16) is divided into an upper section and a lower section by a partition (15), the U-shaped tube (14) is located below the partition (15), and the lower section of the heat pipe assembly (16) extends into the U-shaped tube; The two ends of the U-shaped sleeve (14) are opened upward, and a heat pipe assembly (16) extends into each of the two ends; The U-shaped sleeve (14) is provided with a quenching liquid inlet (19) connected to the liquid storage tank (1), and the U-shaped sleeve (14) is also connected to the liquid outlet (4). The gap between the U-shaped sleeve (14) and the heat pipe assembly is filled with a quenching medium. Under the action of the quenching liquid circulation pump (9) and the circulation pipeline (8), the quenching medium in the liquid storage tank (1) enters the U-shaped sleeve (14) through the quenching liquid inlet (19), and is discharged through the liquid outlet (4) after sufficient heat exchange between the U-shaped sleeve (14) and the heat pipe assembly (16).

7. The quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece according to claim 1, characterized in that: A heat transfer fin (20) is arranged on the outer side of the upper section of the heat pipe assembly (16); A spiral groove (21) is provided on the inner wall surface of the heat pipe assembly (16).

8. The quenching medium air cooling device for obtaining ideal mechanical properties of a quenched workpiece according to claim 2, characterized in that: The heated air discharged from the air cooler housing (5) through the axial flow fan (6) is connected to a heating system or a drying system for heating in winter or drying materials, thereby realizing the reuse of heat energy.

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