CN111715708B - Uniform cooling device and cooling method for wire rod after spinning and coiling - Google Patents
Uniform cooling device and cooling method for wire rod after spinning and coiling Download PDFInfo
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- CN111715708B CN111715708B CN201910216370.1A CN201910216370A CN111715708B CN 111715708 B CN111715708 B CN 111715708B CN 201910216370 A CN201910216370 A CN 201910216370A CN 111715708 B CN111715708 B CN 111715708B
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- air nozzle
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
- B21B45/0224—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes for wire, rods, rounds, bars
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B2045/0212—Cooling devices, e.g. using gaseous coolants using gaseous coolants
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Abstract
The invention discloses a uniform cooling device and a cooling method thereof used after wire rod spinning wire rods, which are arranged below the wire rod spinning wire rods and positioned on a stelmor cooling line, and comprise an air nozzle and a water mist nozzle arranged at the position of an air inlet of the air nozzle; the air inlet to the air outlet of the air nozzle is provided with a gradually-closed structure, namely the width of the air inlet is larger than that of the air outlet, the air nozzle comprises a middle air nozzle and edge air nozzles which are respectively arranged on two sides of the middle air nozzle, and the middle air nozzle and the edge air nozzles are separated by an inclined partition plate; the width of the air outlet of the edge air nozzle is larger than that of the air outlet of the middle air nozzle; the width of the air inlet of the edge air nozzle is larger than that of the air inlet of the middle air nozzle; the length of an air outlet of the middle air nozzle is smaller than the diameter of a wire spinning wire rod; the water mist nozzles are provided with a plurality of groups which are symmetrically arranged at the positions of the air inlets of the edge air nozzles. The invention solves the problems of uneven temperature in the wire cooling process, especially overhigh temperature at the position of the lap joint point, thereby improving the performance uniformity of wire products.
Description
Technical Field
The invention relates to the technical field of cooling after wire rolling, in particular to a uniform cooling device and a cooling method for a wire rod after spinning and coiling, and particularly relates to post-spinning controlled cooling of a wire rod production line using but not limited to a stelmor cooling line.
Background
The wire production line has a plurality of control cooling methods, the most widely used is a stelmor cooling line, and the cooling process is as follows: the coil protruding from the laying head is flatly laid on the roller way, a plurality of groups of fans are arranged below the roller way, cold air blown out by the fans enters the air nozzles below the roller way through the air duct, and the cold air from the air nozzle outlets blows the coil on the roller way to cool the coil.
However, the stelmor cooling line has the disadvantages that the temperature of the lap joint is easily overhigh, the adjusting capacity is limited, coils discharged by a spinning machine are distributed on a roller way as shown in fig. 1, 1 is an edge lap joint, the coils are densely arranged, and 2 is a loose area in the middle of the coil, and the distribution mode of different densities inevitably causes that the cooling of the edge of the coil is slow, the cooling of the middle of the coil is fast, and the temperature of the edge of the coil is higher than that of the middle of the coil, so that the strength difference of the same coil of the coil can be reflected on the product performance.
Although the stelmor cooling line is provided with an adjusting means, the air duct is internally provided with a Jialing device, the air quantity ratio of the edge part and the middle part can be controlled by adjusting the angle of the Jialing device, so that the air quantity of the edge part is large, the air quantity of the middle part is small, and the temperature difference of the same circle caused by the density of the coils is reduced, even if so, the condition of uneven temperature cannot be eliminated. As shown in fig. 2 and 3, the existing tuyere structure is a strip shape with equal height, the width of the air inlet 3 is larger than that of the air outlet 4, but the temperature of the edge part of the coil with different specifications is higher than that of the middle part by 100-150 ℃ through field measurement, and the difference of final cooling temperature causes the inconsistent tissue and grain size of the edge part and the middle part, so that the product performance is uneven.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a uniform cooling device and a cooling method thereof used after a wire rod is spun and coiled, which solve the problems of uneven temperature in the wire rod cooling process, particularly overhigh temperature at the position of a lap joint point, and further improve the performance uniformity of a wire rod product.
In order to achieve the purpose, the invention adopts the following technical scheme:
on one hand, the uniform cooling device for the wire rod spinning wire rod is arranged below the wire rod spinning wire rod and positioned on a stelmor cooling line, and comprises an air nozzle and a water mist nozzle arranged at the air inlet of the air nozzle;
the air inlet to the air outlet of the air nozzle is provided with a gradually-closed structure, namely the width of the air inlet is larger than that of the air outlet, the air nozzle comprises a middle air nozzle and edge air nozzles which are respectively arranged on two sides of the middle air nozzle, the middle air nozzle and the edge air nozzles are separated by an inclined partition plate, the position of the partition plate is determined according to the position of a lap joint point, and the lap joint point is ensured to be positioned in the sweeping range of the edge air nozzle;
the width of the air outlet of the edge air nozzle is larger than that of the air outlet of the middle air nozzle;
the width of the air inlet of the edge air nozzle is greater than or equal to that of the air inlet of the middle air nozzle;
the length of an air outlet of the middle air nozzle is smaller than the diameter of a wire spinning wire rod;
the water mist nozzles are provided with a plurality of groups and are symmetrically arranged at the positions of the air inlets of the edge air nozzles.
The width of the air outlet of the edge air nozzle is 2-5 times that of the air outlet of the middle air nozzle.
The length of an air outlet of the middle air nozzle is 0.7-0.85 times of the diameter of a wire spinning wire rod.
The included angle between the inclined partition plate and the vertical axis of the air nozzle is 5-60 degrees.
In another aspect, a method for uniform cooling of a wire after laying a wire rod, comprising:
determining a good spirit device on a stelmor cooling line and the group number, the position and the flow of water spray nozzles according to the steel grade and the specification, and concretely comprising the following steps:
adjusting the angle of a Jialing device to increase the air quantity of an air nozzle at the edge part of the large-sized wire rod, and simultaneously opening a water mist nozzle to increase the corresponding flow;
small-sized wire rods, because the wire rods are thin in size, the air nozzles uniformly discharge air by adjusting the angle of the linear air conditioning device, and the water mist nozzles do not need to be opened or are opened in a small amount;
for the slow cooling steel without an air nozzle, in order to reduce the overhigh temperature of the lapping position of the wire rod spinning wire rod, a small amount of water mist nozzles are opened to carry out water mist cooling on the lapping position.
And starting the water mist nozzles, specifically turning on corresponding cooling water switches, adjusting the opening degree of a flow regulating valve to meet the water flow requirement, then starting a fan, and after the fan is stabilized, starting the production of the laying head.
The flow density of the water spray nozzle is 0-30 l/m per minute2。
The cooling system provided by the invention is matched with the fan and the Jialing device to adjust the temperature difference of the coils at any position, the air nozzle has a simple and efficient structure, can be in seamless butt joint with the existing roller way system, is very convenient to operate and maintain, and more importantly, the cooling speed of the edge part of the wire rod can be increased under the condition of the same good angle, and the capacity of the fan is fully utilized; the device can realize the uniform cooling problem of the wire rod with the limit specification by combining with the edge part water mist nozzle, is simpler compared with the water mist nozzle, and does not need to introduce a compressed air pipeline. The invention can obviously improve the problem of overlarge temperature difference of the same circle of the air-cooled wire rod, and the product performance is uniform and stable.
Drawings
Fig. 1 is a schematic view of a wire laying wire rod on a transport roller bed;
FIG. 2 is a schematic view of a prior art tuyere structure;
FIG. 3 is a side view of the nozzle structure of FIG. 2;
FIG. 4 is a front view of the cooling device of the present invention;
fig. 5 is a side view of the cooling device of fig. 4.
Detailed Description
The technical scheme of the invention is further explained by combining the drawings and the embodiment.
Referring to fig. 4 to 5, the uniform cooling device for a wire rod after spinning is provided below a wire rod 7 and on a stelmor cooling line, and includes an air nozzle and a water mist nozzle 8 disposed at an air inlet of the air nozzle.
Preferably, the air inlet to the air outlet of tuyere set up to be gradually receive the mouth structure, promptly the air inlet width is greater than the air outlet width, including middle part tuyere 9, and locate the limit portion tuyere 10 of middle part tuyere 9 both sides respectively, through the interval of slope baffle 11 between middle part tuyere 9 and the limit portion tuyere 10, the contained angle of slope baffle 11 and the perpendicular axis of tuyere is 5 ~ 60.
Preferably, the width of the air outlet 12 of the edge air nozzle is 2 to 5 times of the width of the air outlet 13 of the middle air nozzle.
Preferably, the width of the edge tuyere intake opening 14 is greater than or equal to the width of the middle tuyere intake opening 15.
Preferably, the length of the air outlet 13 of the middle air nozzle is 0.7-0.85 times of the diameter of the wire spinning wire rod 7.
Preferably, the water mist nozzles 8 are provided with a single or multiple groups, symmetrically arranged at the positions of the air inlet 14 of the edge air nozzle, and can be selectively opened or closed according to cooling processes of different steel grades, and the opening flow rate can be adjusted.
The cooling devices are arranged in a group along the running direction of the wire spinning wire rod 7, and each cooling device is arranged in the gap position of the connected roller ways. The cooling device of each group can be arranged on the same frame, the gap between the air inlets of the adjacent air nozzles is welded and sealed by steel plates, the air quantity of the fan can only be blown out from the air nozzles, and the cooling devices with different groups can be arranged according to the length of a production line.
When cold air blown by a fan enters from an air inlet of the air nozzle, the air nozzle is of a gradually-closed structure, so that the increase of the air speed of the cold air from the air inlet of the air nozzle to an air outlet of the air nozzle is ensured, the cooling effect is improved, meanwhile, because the air inlet 15 of the middle air nozzle and the air outlet 13 of the middle air nozzle are relatively narrow and the air resistance is relatively large, the air inlet 14 of the edge air nozzle and the air outlet 12 of the edge air nozzle are relatively wide and the air resistance is relatively small, so that the cold air is easier to blow out from the edge air nozzle 10, the cooling effect of the edge of a wire spinning rod 7 is enhanced through the structural design of the air nozzles under the condition that the angle of a smart device is not changed, the inclined partition plate 11 between the middle air nozzle 9 and the edge air nozzle 10 plays a role in guiding the air outlet of the edge air nozzle 10, the cooling air quantity and the cooling capacity of the edge air nozzle 10 are increased, and for the problem of overheating of the edge of the wire spinning rod 7 in a large specification, the wire spinning rod 7 is cooled by the air nozzle combined with the water mist nozzle 8, so that the temperature of the wire spinning rod is uniform, the water mist droplets meet the vaporization of high-temperature wires to take away a large amount of heat, so that the cooling speed of the wires at the position of the lap joint is increased, meanwhile, the surface temperature of the edge roller way can be reduced by the water mist, and the cooling speed of the lap joint of the wires is increased due to the aggravation of the heat conduction and the heat dissipation of the roller way and the coil. Because the air outlet 12 of the edge air nozzle is relatively wide, water mist is more easily dispersed and distributed after passing through the air outlet 12 of the edge air nozzle, and is uniformly sprayed to the surface of the wire rod, so that local supercooling is avoided.
The invention also provides a method for uniformly cooling the wire rod after the wire rod is spun and coiled, which comprises the following steps:
determining a good spirit device on a stelmor cooling line and the group number, the position and the flow of water spray nozzles according to the steel grade and the specification, and concretely comprising the following steps:
and (3) adjusting the angle of the Jialing device to increase the air quantity of the edge air nozzle 10 for large-sized wire rods, and simultaneously opening the water mist nozzle 8 to increase the corresponding flow.
The small-size wire rods are thin in size, the air outlet nozzles uniformly discharge air by adjusting the angle of the linear air conditioner, and the water mist nozzles 8 do not need to be opened or are opened in a small amount.
For the slow cooling steel without an air nozzle, in order to reduce the overhigh temperature of the lapping position of a wire rod spinning wire rod 7, a small amount of water mist nozzles 8 are opened to carry out water mist cooling on the lapping position.
Preferably, the flow density of the water spray nozzle 8 is 0-30 l/m per minute2。
Preferably, the process of starting the water mist nozzles 8 is to open corresponding cooling water switches, adjust the opening of flow regulating valves to meet the water flow requirement, start the fan again, and start the laying head to produce after the process is stable.
According to the actual situation, the length of a production line is 100m, the diameter of a wire rod spinning coil rod 7 is 1.3m, the cooling device is provided with 30 groups, the width of a middle air nozzle air inlet 15 is equal to the width of a middle air nozzle air outlet 13 and is 25mm, the width of an edge air nozzle air outlet 12 is 4 times of the width of the middle air nozzle air outlet 13 and is 100mm, the width of an edge air nozzle air inlet 14 is 150mm, the length of the middle air nozzle air outlet 13 is 0.76 times of the diameter of the wire rod spinning coil rod 7 and is 1m, the included angle between an inclined partition plate 11 and the vertical axis of the air nozzle is 25 degrees, 4 water spray nozzles 8 at the position of the edge air nozzle air inlet 14 are arranged, and the flow density of the water spray nozzles 8 is 17l/m2Min, pressure 2 bar.
The temperature difference between the edge part and the middle part of the coil is reduced to 30-70 ℃ from 100-150 ℃ when the cooling device is not used, and the temperature uniformity of the same coil is obviously improved. The embodiment of the invention is concretely as follows:
example 1: the diameter of a certain hard wire rod with the diameter of 5.5mm is 880 ℃, only an air nozzle is used, a water mist nozzle 8 is not used, and the actually measured temperature difference of the same circle is 55 ℃.
Example 2: cold heading steel wire rod with diameter of 8mm, spinning temperature of 840 ℃, slow cooling without opening a fan, using 12 groups of water mist nozzles 8, installing 1 water mist nozzle 8 at the position of an air inlet 14 of an air nozzle at the upper edge part of each cooling device, wherein the flow density of the water mist nozzles 8 is 17l/m2Min, the measured temperature difference in the same circle is 70 ℃.
Example 3: a certain hard wire rod with the diameter of 14mm, the spinning temperature of 860 ℃, 8 groups of water mist nozzles 8, 2 water mist nozzles 8 arranged at the air inlet 14 of the air nozzle at the upper edge part of each cooling device, the space between the water mist nozzles 8 is 80mm, and the flow density of the water mist nozzles 8 is 10l/m2Min, the measured temperature difference in the same circle is 50 ℃.
Example 4: a certain hard wire rod with the diameter of 24mm, the spinning temperature of 910 ℃, 16 groups of water mist nozzles 8, and an air inlet 14 of an upper edge air nozzle of each cooling device3 water mist nozzles 8 are arranged at the positions, the distance between the water mist nozzles 8 is 60mm, and the flow density of the water mist nozzles 8 is 15l/m2Min, the measured temperature difference in the same circle is 45 ℃.
It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above described embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.
Claims (6)
1. The utility model provides an even cooling device behind wire rod that is used for laying a silk, locates the below of wire rod that lays a silk, and is located stelmor cooling line, its characterized in that: comprises an air nozzle and a water mist nozzle arranged at the air inlet of the air nozzle;
the air inlet to the air outlet of the air nozzle are arranged into a gradually-closed structure, namely the width of the air inlet is larger than that of the air outlet; the air nozzles comprise a middle air nozzle and edge air nozzles respectively arranged on two sides of the middle air nozzle, and the middle air nozzle and the edge air nozzles are separated by an inclined partition plate;
the width of the air outlet of the edge air nozzle is larger than that of the air outlet of the middle air nozzle;
the width of an air inlet of the edge air nozzle is larger than that of an air inlet of the middle air nozzle;
the length of an air outlet of the middle air nozzle is smaller than the diameter of a wire spinning wire rod;
the water spray nozzles are provided with a plurality of groups which are symmetrically arranged at the positions of the air inlets of the edge air nozzles,
the length of an air outlet of the middle air nozzle is 0.7-0.85 times of the diameter of a wire spinning wire rod.
2. The device for uniformly cooling the wire after the wire is spun and coiled as in claim 1, wherein: the width of the air outlet of the edge air nozzle is 2-5 times that of the air outlet of the middle air nozzle.
3. The device for uniformly cooling the wire after the wire is spun and coiled as in claim 1, wherein: the included angle between the inclined partition plate and the vertical axis of the air nozzle is 5-60 degrees.
4. A cooling method for the uniform cooling device after the wire rod is spun by the wire rod according to any one of claims 1 to 3, characterized in that: the method comprises the following steps:
adjusting a linear cooling device on a stelmor cooling line and the group number, the position and the flow of water spray nozzles according to the steel grade and the specification, and specifically comprising the following steps:
adjusting the angle of a Jialing device to increase the air quantity of an air nozzle at the edge part of the large-sized wire rod, and simultaneously opening a water mist nozzle to increase the flow of the water mist nozzle;
small-sized wire rods, because the wire rods are thin in size, the air nozzles uniformly discharge air by adjusting the angle of the linear air conditioning device, and the water mist nozzles do not need to be opened or are opened in a small amount;
for the slow cooling steel without an air nozzle, in order to reduce the overhigh temperature of the lapping position of the wire rod spinning wire rod, a small amount of water mist nozzles are opened to carry out water mist cooling on the lapping position.
5. The cooling method for the uniform cooling device after the wire rod is spun by the wire rod as in claim 4, wherein: and starting the water mist nozzles, specifically turning on corresponding cooling water switches, adjusting the opening degree of a flow regulating valve to meet the water flow requirement, then starting a fan, and after the fan is stabilized, starting the production of the laying head.
6. The cooling method for the uniform cooling device after the wire rod is spun by the wire rod according to claim 5, wherein the cooling method comprises the following steps: the flow density of the water spray nozzle is 0-30L/m2·min。
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CN201910216370.1A CN111715708B (en) | 2019-03-21 | 2019-03-21 | Uniform cooling device and cooling method for wire rod after spinning and coiling |
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CN112496062B (en) * | 2020-10-20 | 2022-07-22 | 江苏省沙钢钢铁研究院有限公司 | Method for improving performance uniformity of high-carbon steel wire rod in same circle |
CN113600623A (en) * | 2021-08-06 | 2021-11-05 | 新疆八一钢铁股份有限公司 | Method for inhibiting high-carbon steel wire rod SWRH82B core net-shaped cementite |
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KR200167198Y1 (en) * | 1995-12-29 | 2000-03-02 | 이구택 | Apparatus for cooling acceleration a middle of wire rod cooling zone |
KR100507573B1 (en) * | 2000-11-27 | 2005-08-17 | 주식회사 포스코 | Method for cooling wire-rod with controlled rolling and apparatus for cooling the same |
CN105436214B (en) * | 2014-08-27 | 2019-06-25 | 宝山钢铁股份有限公司 | A kind of wire rod edge cooling device and wire rod edge cooling means |
CN204842486U (en) * | 2015-07-24 | 2015-12-09 | 邢台钢铁有限责任公司 | Improve fan of rod rolling roll table forced air cooling ability |
CN108339859B (en) * | 2018-01-11 | 2020-01-17 | 上海大学 | Stelmor air cooling line and air box tuyere structure thereof |
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