A water spray cooling device for heat treatment of metal bars

Abstract

The present invention discloses a water spray cooling device for heat treatment of metal bars, which belongs to the field of metal heat treatment technology, including a single-zone nozzle array, a water supply system and a control system. The single-zone nozzle array linear array constitutes a multi-zone nozzle array. The heat-treated metal bar is cooled in the multi-zone nozzle array. The water supply system is used to supply water to each single-zone nozzle array, and the control system is used to control the water supply system. The beneficial effects of the present invention are as follows: 1. Improve the cooling rate of the metal bar. 2. Make the circumferential cooling rate of the metal bar more uniform. 3. Multiple single-zone nozzle arrays are combined into a multi-zone nozzle array to cool the metal bar in sections, and each single-zone nozzle array can independently control the flow rate and pressure of the spray, so that the cooling rate can be controlled. 4. It can achieve both uniform axial cooling of the entire metal bar and axial gradient cooling of the metal bar.

Description

Technical Field

[0001] The invention relates to the technical field of metal heat treatment, in particular to a water spray cooling device for heat treatment of metal bars. Background Art

[0002] Some special metals, such as aluminum alloys, may require selective cooling of the bar before the extrusion process to give the material specific metallurgical properties, significantly increase the extrusion speed and optimize the metal quality. And due to the production cycle, air cooling cannot meet the required power density, and water cooling becomes a necessary choice.

[0003] Generally, metal bars are cooled by immersion cooling. However, in the initial stage of immersion cooling, since the temperature of the high-temperature bar is much higher than the Leidenfrost point, the bar enters the film boiling stage as a whole, and forms a thin steam film on the surface to isolate it from the liquid water. Due to the poor thermal conductivity of the steam film, the heat transfer between the metal workpiece and the water is very slow. Moreover, for the cooling of the bar before the extrusion process, the cooling process ends before the bar drops to a very low temperature and enters the bubbling boiling stage and convection stage with faster thermal conductivity. On the other hand, the shape of the steam film on the upper and lower parts of the bar is quite different, which can easily lead to uneven temperatures on the upper and lower parts of the bar, that is, uneven circumferential temperature. In short, immersion cooling has the following problems: slow cooling, uneven temperature circumferentially, difficulty in achieving axial temperature gradient, uncontrollable cooling speed, etc. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a water spray cooling device for heat treatment of metal bars, and the present invention is achieved through the following technical solutions.

[0005] A water spray cooling device for heat treatment of metal bars comprises a single-zone nozzle array, a water supply system and a control system. The single-zone nozzle array linear array forms a multi-zone nozzle array. The heat-treated metal bars are cooled in the multi-zone nozzle array. The water supply system is used to supply water to each single-zone nozzle array, and the control system is used to control the water supply system.

[0006] Preferably, the single-zone nozzle array includes a water inlet pipe, a water spray pipe and a nozzle body; a pair of vertical pipes are fixedly connected to the water inlet pipe at intervals, the vertical pipes and the water inlet pipe form an "F" shape, a pair of horizontal pipes are fixedly connected to the side of the vertical pipes close to each other, the water spray pipes are semicircular and arranged in pairs, the two paired water spray pipes form a circle, the water spray pipes are connected to the horizontal pipes, the nozzle body is arranged on the inner side of the water spray pipe, the nozzle bodies on the two paired water spray pipes are evenly arranged around the circumference, and the water supply system is connected to the water inlet pipe.

[0007] Preferably, the nozzle body is threadedly connected to the water spray pipe.

[0008] Preferably, a plurality of pairs of the water spray pipes are evenly arranged along the length direction of the horizontal pipe, and the nozzle bodies on two adjacent pairs of water spray pipes are staggered.

[0009] Preferably, it also includes a box body, in which a grille plate is fixedly connected, and a spray chamber and a water storage chamber are formed on the upper and lower sides of the grille plate respectively. The water storage chamber is used to hold cooling water, and feed ports and discharge ports are provided on both sides of the spray chamber. Cover plates are provided at the feed ports and discharge ports, and the multi-zone nozzle array is installed on the grille plate.

[0010] Preferably, the bottom of the box body is connected to the drain outlet through a first valve, and the lower part of one side of the box body is connected to the water replenishment port through a water replenishment pipe, and a second valve is provided on the water replenishment pipe.

[0011] Preferably, a liquid level regulator is provided on the water supply pipe, and a liquid level meter is provided in the water storage chamber.

[0012] Preferably, the water supply system includes a variable frequency water pump, a cooler, a filter and a flange valve; the variable frequency water pump is connected to the bottom of the water storage chamber through a pipe, the outlet of the variable frequency water pump is connected to the inlet of the cooler through a pipe, the outlet of the cooler is connected to the inlet of the filter, the outlet of the filter is connected to the inlet of the flange valve, the outlet of the flange valve is connected to a plurality of branch pipes through a pipe, and the other end of the branch pipe is connected to the water inlet pipe.

[0013] Preferably, a first thermometer and a pressure relief valve are connected to the pipeline between the inlet of the cooler and the outlet of the variable frequency water pump; a differential pressure gauge is connected between the inlet and outlet of the filter through a pipeline; and a second thermometer is connected to the outlet of the flange valve.

[0014] Preferably, the control system includes a controller and control software, the control software is used to transmit instructions to the controller, the branch pipe is connected to a control valve, the outlet pipe of the flange valve is connected to a pressure gauge and a flow meter, the single-zone nozzle array is fixedly connected to a thermocouple, the control output end of the controller is connected to a variable frequency water pump and a control valve, and the signal input end of the controller is connected to a pressure gauge, a flow meter and a thermocouple.

[0015] The beneficial effects of the present invention are as follows: 1. Spray cooling through the nozzle body can avoid the problem of slow cooling caused by the generation of steam film compared to traditional immersion cooling.

[0016] 2. The nozzle body sprays evenly in the circumferential direction, which can make the circumferential cooling speed of the metal bar consistent and make the cooling speed more uniform.

[0017] 3. Multiple single-zone nozzle arrays are combined into a multi-zone nozzle array. Multiple single-zone nozzle arrays cool the metal bar in sections, and each single-zone nozzle array can independently control the flow rate and pressure of the spray, so that the cooling speed can be controlled.

[0018] 4. Each single-zone nozzle array can independently control the spray flow and pressure, which can achieve uniform axial cooling of the entire metal bar and axial gradient cooling of the metal bar. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the description of the specific implementation methods will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 : 3D schematic diagram of multi-zone nozzle array; Figure 2 : 3D schematic diagram of a single-zone nozzle array; Figure 3 : Schematic diagram of thermocouple installation; Figure 4 : A schematic structural diagram of a water spray cooling device for heat treatment of metal bars according to the present invention; Figure 5 : Circuit connection diagram of the control system described in the present invention.

[0021] The reference numerals are as follows: 11-water inlet pipe, 12-water spray pipe, 13-nozzle body, 14-vertical pipe, 15-horizontal pipe, 21-frequency conversion water pump, 22-cooler, 23-filter, 24-flange valve, 25-branch pipe, 26-first thermometer, 27-pressure relief valve, 28-differential pressure gauge, 29-second thermometer, 31-controller, 32-control software, 33-control valve, 34-pressure gauge, 35-flow meter, 36-thermocouple, 4-box, 41-grid plate, 42-spray chamber, 43-water storage chamber, 44-cooling water, 45-feed port, 46-discharge port, 47-cover plate, 48-first valve, 49-drain port, 410-water supply pipe, 411-water supply port, 412-second valve, 413-liquid level regulator, 414-liquid level gauge. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] like Figure 1-5 As shown, a water spray cooling device for heat treatment of metal bars includes a single-zone nozzle array, a water supply system and a control system. The single-zone nozzle array linear array constitutes a multi-zone nozzle array. The heat-treated metal bars are cooled in the multi-zone nozzle array. The water supply system is used to supply water to each single-zone nozzle array, and the control system is used to control the water supply system.

[0024] Furthermore, the single-zone nozzle array includes a water inlet pipe 11, a water spray pipe 12 and a nozzle body 13; a pair of vertical pipes 14 are fixedly connected to the water inlet pipe 11 at intervals, the vertical pipes 14 and the water inlet pipe 11 form an "F" shape, a pair of horizontal pipes 15 are fixedly connected to the side of the vertical pipes 14 close to each other, the water spray pipes 12 are semicircular and arranged in pairs, the two paired water spray pipes 12 form a circle, the water spray pipes 12 are connected to the horizontal pipes 15, the nozzle body 13 is arranged on the inner side of the water spray pipe 12, the nozzle bodies 13 on the two paired water spray pipes 12 are evenly arranged around the circumference, and the water supply system is connected to the water inlet pipe 11.

[0025] Furthermore, the nozzle body 13 is threadedly connected to the water spray pipe 12 .

[0026] Furthermore, a plurality of pairs of water spray pipes 12 are evenly arranged along the length direction of the transverse pipe 15 , and the nozzle bodies 13 on two adjacent pairs of water spray pipes 12 are staggered.

[0027] Furthermore, it also includes a box body 4, in which a grille plate 41 is fixedly connected, and a spray chamber 42 and a water storage chamber 43 are formed on the upper and lower sides of the grille plate 41 respectively. The water storage chamber 43 is used to hold cooling water 44, and a feed port 45 and a discharge port 46 are provided on both sides of the spray chamber 42. Cover plates 47 are provided at the feed port 45 and the discharge port 46, and a multi-zone nozzle array is installed on the grille plate 41.

[0028] Furthermore, the bottom of the box body 4 is connected to the drain port 49 via a first valve 48 , and the lower part of one side of the box body 4 is connected to the water replenishment port 411 via a water replenishment pipe 410 , and a second valve 412 is provided on the water replenishment pipe 410 .

[0029] Furthermore, a liquid level regulator 413 is provided on the water supply pipe 410 , and a liquid level meter 414 is provided in the water storage chamber 43 .

[0030] Furthermore, the water supply system includes a variable frequency water pump 21, a cooler 22, a filter 23 and a flange valve 24; the variable frequency water pump 21 is connected to the bottom of the water storage chamber 43 through a pipeline, the outlet of the variable frequency water pump 21 is connected to the inlet of the cooler 22 through a pipeline, the outlet of the cooler 22 is connected to the inlet of the filter 23, the outlet of the filter 23 is connected to the inlet of the flange valve 24, the outlet of the flange valve 24 is connected to a plurality of branch pipes 25 through a pipeline, and the other end of the branch pipe 25 is connected to the water inlet pipe 11.

[0031] Furthermore, a first thermometer 26 and a pressure relief valve 27 are connected to the pipeline between the inlet of the cooler 22 and the outlet of the variable frequency water pump 21; a differential pressure gauge 28 is connected between the inlet and outlet of the filter 23 through a pipeline; and a second thermometer 29 is connected to the outlet of the flange valve 24.

[0032] Furthermore, the control system includes a controller 31 and control software 32, the control software 32 is used to transmit instructions to the controller 31, the branch pipe 25 is connected to a control valve 33, the outlet pipe of the flange valve 24 is connected to a pressure gauge 34 and a flow meter 35, a thermocouple 36 is fixed to the single-zone nozzle array, the control output end of the controller 31 is connected to the variable frequency water pump 21 and the control valve 33, and the signal input end of the controller 31 is connected to the pressure gauge 34, the flow meter 35 and the thermocouple 36.

[0033] A specific embodiment of the present invention is: like Figure 4 As shown, after the metal bar is heat treated in the induction furnace, its temperature generally reaches 550-560°C. The heat-treated metal bar is fed into the spray chamber 42 through the feed port 45 and located at the center of the multi-zone nozzle array. The feed port 45 is then sealed by a cover plate 47 to prevent water and water vapor from escaping.

[0034] The water supply system extracts cooling water 44 and sprays it through a multi-zone nozzle array to act on the metal bar material to cool the metal bar material. The sprayed water flows back to the water storage chamber 43 through the grid plate 41 for continued use, thereby realizing the recycling of cooling water 44.

[0035] When there are many impurities in the cooling water 44, the first valve 48 can be opened to discharge sewage through the drain port 49; when the cooling water 44 is lost after being discharged or during use, the cooling water 44 is replenished through the water replenishment port 411 and the water replenishment pipe 410. A liquid level meter 414 and a liquid level regulator 413 are provided to control the depth of the cooling water 44.

[0036] When the water supply system is working, water is pumped by the variable frequency water pump 21 and transported to the cooler 22 for cooling, so that the cooling water 44 is kept at a lower temperature to improve the cooling effect. The cooled cooling water 44 is filtered through the filter 23 to remove impurities and is transported to the water inlet pipe 11 through the branch pipe 25.

[0037] like Figure 1-Figure 2 As shown, cooling water 44 enters the water spray pipe 12 through the water inlet pipe 11, the vertical pipe 14 and the horizontal pipe 15, and is sprayed out through the nozzle body 13, thereby cooling the metal bar. The nozzle body 13 is threadedly connected to the water spray pipe 12, which is convenient for replacing nozzles of different models.

[0038] like Figure 4 As shown, during the spray cooling process, the temperature of the cooling water 44 is measured by the first thermometer 26 and the second thermometer 29, and the flow rate and pressure of the cooling water 44 are measured and recorded by the flow meter 35 and the pressure gauge 34.

[0039] like Figure 3 and Figure 5 As shown, a thermocouple 36 is provided on each single-zone nozzle array, that is, a plurality of thermocouples 36 are provided in the length direction of the metal bar, the surface temperature of the metal bar at each single-zone nozzle array position is monitored in real time, and the internal temperature of the metal bar is estimated by the surface temperature, and the opening and closing size of the control valve 33 can be adjusted according to the temperature at each position, so that the cooling speed can be accurately controlled, and both uniform cooling of the whole bar and axial gradient cooling of the whole bar can be achieved.

[0040] When the overall cooling speed is lower than expected, the speed of the variable frequency water pump 21 is increased, and the flow rate, pressure and injection speed are increased, so the cooling speed is increased. Otherwise, the reverse operation is performed.

[0041] When the temperature of the metal bar reaches the target, it is moved out of the spray chamber 42 through the discharge port 46 .

[0042] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A water spray cooling device for heat treatment of metal bars, characterized in that: It includes a single-zone nozzle array, a water supply system and a control system. The single-zone nozzle array linear array forms a multi-zone nozzle array. The heat-treated metal bar is cooled in the multi-zone nozzle array. The water supply system is used to supply water to each single-zone nozzle array, and the control system is used to control the water supply system.

2. A water spray cooling device for heat treatment of metal bars according to claim 1, characterized in that: The single-zone nozzle array comprises a water inlet pipe (11), a water spray pipe (12) and a nozzle body (13); a pair of vertical pipes (14) are fixedly connected to the water inlet pipe (11) at intervals, the vertical pipes (14) and the water inlet pipe (11) form an "F" shape, a pair of horizontal pipes (15) are fixedly connected to the sides of the vertical pipes (14) close to each other, the water spray pipes (12) are semicircular and arranged in pairs, the two paired water spray pipes (12) form a circle, the water spray pipes (12) are connected to the horizontal pipes (15), the nozzle body (13) is arranged on the inner side of the water spray pipe (12), the nozzle bodies (13) on the two paired water spray pipes (12) are evenly arranged around the circumference, and the water supply system is connected to the water inlet pipe (11).

3. A water spray cooling device for heat treatment of metal bars according to claim 2, characterized in that: The nozzle body (13) is threadedly connected to the water spray pipe (12).

4. A water spray cooling device for heat treatment of metal bars according to claim 2, characterized in that: A plurality of pairs of the water spray pipes (12) are evenly arranged along the length direction of the transverse pipe (15), and the nozzle bodies (13) on two adjacent pairs of the water spray pipes (12) are staggered.

5. The water spray cooling device for heat treatment of metal bars according to claim 2, characterized in that: It also includes a box body (4), a grille plate (41) is fixedly connected to the box body (4), a spray chamber (42) and a water storage chamber (43) are formed on the upper and lower sides of the grille plate (41), the water storage chamber (43) is used to hold cooling water (44), a feed port (45) and a discharge port (46) are provided on both sides of the spray chamber (42), a cover plate (47) is provided at the feed port (45) and the discharge port (46), and the multi-zone nozzle array is mounted on the grille plate (41).

6. A water spray cooling device for heat treatment of metal bars according to claim 5, characterized in that: The bottom of the box body (4) is connected to the drain port (49) via a first valve (48), and the lower part of one side of the box body (4) is connected to the water replenishment port (411) via a water replenishment pipe (410), and a second valve (412) is provided on the water replenishment pipe (410).

7. A water spray cooling device for heat treatment of metal bars according to claim 6, characterized in that: A liquid level regulator (413) is provided on the water supply pipe (410), and a liquid level meter (414) is provided in the water storage chamber (43).

8. The water spray cooling device for heat treatment of metal bars according to claim 5, characterized in that: The water supply system comprises a variable frequency water pump (21), a cooler (22), a filter (23) and a flange valve (24); the variable frequency water pump (21) is connected to the bottom of the water storage chamber (43) through a pipeline, the outlet of the variable frequency water pump (21) is connected to the inlet of the cooler (22) through a pipeline, the outlet of the cooler (22) is connected to the inlet of the filter (23), the outlet of the filter (23) is connected to the inlet of the flange valve (24), the outlet of the flange valve (24) is connected to a plurality of branch pipes (25) through a pipeline, and the other end of the branch pipe (25) is connected to the water inlet pipe (11).

9. A water spray cooling device for heat treatment of metal bars according to claim 8, characterized in that: A first thermometer (26) and a pressure relief valve (27) are connected to the pipeline between the inlet of the cooler (22) and the outlet of the variable frequency water pump (21); a differential pressure gauge (28) is connected between the inlet and outlet of the filter (23) via a pipeline; and a second thermometer (29) is connected to the outlet of the flange valve (24).

10. A water spray cooling device for heat treatment of metal bars according to claim 8, characterized in that: The control system comprises a controller (31) and control software (32), wherein the control software (32) is used to transmit instructions to the controller (31); the branch pipe (25) is connected to a control valve (33); the outlet pipe of the flange valve (24) is connected to a pressure gauge (34) and a flow meter (35); a thermocouple (36) is fixedly connected to the single-zone nozzle array; the control output end of the controller (31) is connected to a variable frequency water pump (21) and the control valve (33); and the signal input end of the controller (31) is connected to the pressure gauge (34), the flow meter (35) and the thermocouple (36).

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