阅读说明：本技术 一种消除球墨铸铁白口缺陷的热处理工艺 (Heat treatment process for eliminating ductile iron white defects ) 是由 关杨 张宏涛 于 2020-05-22 设计创作，主要内容包括：本发明属于热处理技术领域,具体的说是一种消除球墨铸铁白口缺陷的热处理工艺,该工艺中使用的空冷装置包括风筒,所述风筒的一端固定有圆环,所述圆环内侧壁上固定有吸水盘,所述吸水盘采用吸水树脂材料制成,所述风筒内腔靠近圆环的一端固定有抽风机,所述抽风机用于抽取空气,所述抽风机远离圆环的一侧设有加热网,所述加热网用于调节进入风筒的空气的温度,所述风筒内设有两个导轨,两个所述导轨上活动安装有放置架；本发明通过将空气中的水分吸收过滤,且对进入风筒的空气进行加热,使得与球墨铸铁件接触的空气为干燥且非低温的,从而避免了空冷过程中球墨铸铁件可能发生的变形和开裂问题,进而保证了球墨铸铁件的热处理效果。(The invention belongs to the technical field of heat treatment, in particular to a heat treatment process for eliminating a nodular cast iron white cast defect, wherein an air cooling device used in the process comprises an air duct, a circular ring is fixed at one end of the air duct, a water absorption disc is fixed on the inner side wall of the circular ring and is made of a water absorbent resin material, an exhaust fan is fixed at one end of the inner cavity of the air duct, which is close to the circular ring, and is used for extracting air, a heating net is arranged at one side of the exhaust fan, which is far away from the circular ring, and is used for adjusting the temperature of the air entering the air duct, two guide rails are arranged in the air duct, and a placing frame is movably arranged on the two guide rails; according to the invention, moisture in the air is absorbed and filtered, and the air entering the air duct is heated, so that the air in contact with the nodular iron castings is dry and not low-temperature, thereby avoiding the problems of deformation and cracking of the nodular iron castings possibly occurring in the air cooling process, and further ensuring the heat treatment effect of the nodular iron castings.)

1. A heat treatment process for eliminating the white defects of nodular cast iron is characterized by comprising the following steps:

s1: putting the nodular iron castings to be treated into a tempering furnace for heating, so that the temperature of the nodular iron castings is raised to the annealing temperature, the temperature rise time is ensured to be 2-4 hours, and the temperature is kept for 2-4 hours;

s2: gradually reducing the temperature of the tempering furnace in S1 to ensure that the ductile iron casting is cooled to 680-750 ℃ at the speed of 5-10 ℃/h and then cooled to 450-550 ℃ at the speed of 20-30 ℃/h;

s3: the nodular iron castings in the S2 are placed into an air cooling device for air cooling, an exhaust fan (4) extracts air to enter an air duct (1) during air cooling, a water absorption disc (3) filters water vapor in the air, a heating net (5) is used for adjusting the temperature of the air entering the air duct (1) to enable the air entering the air duct (1) to be dry and at a proper temperature, and the nodular iron castings are taken out after the air cooling is finished;

wherein the air cooling device used in S3 comprises an air duct (1), a circular ring (2) is fixed at one end of the air duct (1), a water absorbing disc (3) is fixed on the inner side wall of the circular ring (2), the water absorbing disc (3) is made of water absorbing resin material, an exhaust fan (4) is fixed at one end of the inner cavity of the wind barrel (1) close to the circular ring (2), the exhaust fan (4) is used for extracting air, one side of the exhaust fan (4) far away from the ring (2) is provided with a heating net (5), the heating net (5) is used for adjusting the temperature of the air entering the air duct (1), two guide rails (6) are arranged in the air duct (1), a placing rack (7) is movably arranged on the two guide rails (6), the rack (7) is of a net structure, a controller is arranged on the air duct (1), and the controller is used for controlling the air cooling device to work.

2. The heat treatment process for eliminating the ductile iron white cast iron defects according to claim 1, wherein: be equipped with baffle group more than two along its length direction equidistance on the inside wall of dryer (1), every baffle group includes baffle (8) of the equidistance rotation installation of more than two along dryer (1) circumference, be equipped with return air hole (9) more than two on the inside wall of dryer (1), return air hole (9) and baffle (8) one-to-one, the entrance of return air hole (9) is equipped with air collecting plate (10).

3. The heat treatment process for eliminating the ductile iron white cast iron defects according to claim 2, wherein: the air return hole (9) is of an annular structure, the air outlet direction of the air return hole (9) faces away from the direction of the circular ring (2), the side face of the baffle (8) is of a triangular structure, the top face of the baffle (8) is aligned to the outlet of the air return hole (9), and the diameter value of the outlet of the air return hole (9) is smaller than the diameter value of the inlet of the air return hole.

4. The heat treatment process for eliminating the ductile iron white cast iron defects according to claim 3, wherein: dryer (1) inside wall is equipped with disc (11), be equipped with through-hole (12) more than two on disc (11), one side that ring (2) were kept away from in through-hole (12) is equipped with the hose, shower nozzle (13) more than two are passed through breeches pipe fixedly connected with to the one end that through-hole (12) were kept away from to the hose, and shower nozzle (13) circumference distribution with same hose connection is on the inside wall of dryer (1).

5. The heat treatment process for eliminating the ductile iron white defects according to claim 4, wherein: the spray head (13) is arranged between the two baffle groups, the diameter value of the through hole (12) becomes larger along with the distance value between the spray head (13) connected with the through hole and the circular ring (2), and the through hole (12) positioned at the center of the circular disc (11) is not connected with a hose.

6. The heat treatment process for eliminating the ductile iron white cast iron defects according to claim 2, wherein: the one end that ring (2) were kept away from in dryer (1) is fixed with thermal-arrest frame (14), thermal-arrest frame (14) are V font structure, thermal-arrest frame (14) are connected with water absorption dish (3) through the wire, and the wire inserts the outer lane lateral wall of water absorption dish (3), the outer lane of water absorption dish (3) is loose structure, the diameter value of water absorption dish (3) is greater than the internal diameter value of dryer (1).

Technical Field

The invention belongs to the technical field of heat treatment, and particularly relates to a heat treatment process for eliminating a nodular cast iron white cast iron defect.

Background

The ductile iron is a high-strength cast iron material developed in the 20 th century and the fifties, the comprehensive performance of the ductile iron is close to that of steel, and the ductile iron is successfully used for casting parts which are complex in stress and high in requirements on strength, toughness and wear resistance based on the excellent performance of the ductile iron. Nodular cast iron has rapidly evolved to a very widely used cast iron material second only to gray cast iron. The term "steel is replaced by iron" is mainly used for nodular cast iron. The nodular cast iron is spheroidized and inoculated to obtain spheroidal graphite, so that the mechanical properties of the cast iron are effectively improved, and particularly, the plasticity and toughness are improved, so that the strength of the cast iron is higher than that of carbon steel.

In addition to casting defects, the ductile cast iron also has some special metallographic structure defects in production, such as microscopic slag inclusion, graphite floating and flowering graphite, poor spheroidization and degradation of spheroidization, white cast iron and reverse white cast iron, flake graphite pre-crushed block graphite, phosphorus eutectic crystal and the like. The white structure is hard and brittle, so that the casting is always processed immovably or is subjected to 'knife hitting' in the processing process, cracks are easily generated in the carrying process, and the casting body is easily peeled off.

Disclosure of Invention

In order to make up for the defects of the prior art, the air cooling device used in the heat treatment process for eliminating the ductile iron white cast defect absorbs and filters moisture in air and heats the air entering the air duct, so that the air in contact with the ductile iron castings is dry and not low-temperature, the problems of deformation and cracking of the ductile iron castings possibly occurring in the air cooling process are avoided, and the heat treatment effect of the ductile iron castings is further ensured.

The technical scheme adopted by the invention for solving the technical problems is as follows: the invention relates to a heat treatment process for eliminating ductile iron white defects, which comprises the following steps:

s1: putting the nodular iron castings to be treated into a tempering furnace for heating, so that the temperature of the nodular iron castings is raised to the annealing temperature, the temperature rise time is ensured to be 2-4 hours, and the temperature is kept for 2-4 hours;

s2: gradually reducing the temperature of the tempering furnace in S1 to ensure that the ductile iron casting is cooled to 680-750 ℃ at the speed of 5-10 ℃/h and then cooled to 450-550 ℃ at the speed of 20-30 ℃/h;

s3: the method comprises the following steps of (1) putting the nodular iron castings in S2 into an air cooling device for air cooling, wherein an exhaust fan extracts air to enter an air duct during air cooling, a water absorption disc filters water vapor in the air, a heating net is used for regulating the temperature of the air entering the air duct, so that the air entering the air duct is dry and at a proper temperature, the nodular iron castings are taken out after the air cooling is finished, the air cooling device absorbs and filters moisture in the air, the air entering the air duct is heated, the air in contact with the nodular iron castings is dry and not at a low temperature, and the baffle is used for guiding the air so that the nodular iron castings are in uniform contact with the air, the problems of deformation and cracking of the nodular iron castings possibly occurring in the air cooling process are avoided, and the heat treatment effect of the nodular iron castings is further ensured;

the air cooling device used in the S3 comprises an air duct, wherein a circular ring is fixed at one end of the air duct, a water absorption disc is fixed on the inner side wall of the circular ring, the water absorption disc is made of a water-absorbent resin material, an exhaust fan is fixed at one end, close to the circular ring, of the inner cavity of the air duct and is used for extracting air, a heating net is arranged at one side, away from the circular ring, of the exhaust fan and is used for adjusting the temperature of the air entering the air duct, two guide rails are arranged in the air duct, placing frames are movably mounted on the two guide rails and are of a net-shaped structure, a controller is arranged on the air duct and is used for controlling the air cooling device to work; when the air cooling device is used, in winter in the south, because the air humidity is high and the air temperature is low, the nodular iron castings are cooled unevenly during air cooling, so that the nodular iron castings are easy to deform or crack, and the production quality of the nodular iron castings is further influenced, and the problem is improved; when air cooling operation is carried out, the nodular iron castings are placed on the placing rack, then the placing rack is pushed into the air duct, and meanwhile, the air cooling device is started; when the air cooling device is started, the exhaust fan works, so that air is pumped into the air cylinder; before entering the air duct, the air needs to pass through the water absorption disc, and moisture in the air is absorbed when the air passes through the water absorption disc; the dried air enters the inner cavity of the air duct and is heated by the heating net, so that the temperature of the air is adjusted; the processed air moves in the inner cavity of the air duct and is blown out from one end of the air duct far away from the exhaust fan; the nodular iron castings are contacted with the nodular iron castings in the air moving process, so that the nodular iron castings are in a normal air cooling environment, and normal air cooling is guaranteed; according to the invention, moisture in the air is absorbed and filtered, and the air entering the air duct is heated, so that the air in contact with the nodular iron castings is dry and not low-temperature, thereby avoiding the problems of deformation and cracking of the nodular iron castings possibly occurring in the air cooling process, and further ensuring the heat treatment effect of the nodular iron castings.

Preferably, more than two baffle groups are arranged on the inner side wall of the air duct at equal intervals along the length direction of the air duct, each baffle group comprises more than two baffles which are rotatably arranged at equal intervals along the circumferential direction of the air duct, more than two air return holes are formed in the inner side wall of the air duct, the air return holes correspond to the baffles one to one, and an air collecting plate is arranged at an inlet of each air return hole; when the cooling device is used, air moves transversely in the process of moving in the inner cavity of the air duct, and if the nodular iron castings are complex in shape or have cavities, the air cannot be in full contact with the nodular iron castings, so that the cooling speed and the cooling uniformity of the nodular iron castings are limited; the baffle is arranged, so that the baffle can be contacted with the baffle in the air moving process, and the baffle rotates; guiding air to the nodular iron castings in the rotating process of the baffle plate to enable the nodular iron castings to be fully contacted with the air; after the baffle rotates, the air moves to the position of the air collecting plate beyond the baffle, the air enters the air return hole after being guided by the air collecting plate, and the air entering the air return hole moves to the outlet of the air return hole to be blown out, so that the baffle rotates reversely; the air is continuously guided by the baffle plate, so that the air is in good contact with the nodular iron castings, and the air cooling effect is improved.

Preferably, the air return hole is of an annular structure, the air outlet direction of the air return hole is back to the direction of the ring, the side surface of the baffle is of a triangular structure, the outlet of the air return opening is aligned to the top surface of the baffle, and the diameter value of the outlet of the air return hole is smaller than that of the inlet of the air return hole; when the air return hole is used, the air outlet of the air return hole faces the direction of the circular ring, so that air is easily fed from two ends of the air return hole, and the using effect of the air outlet is influenced; the outlet of the return air hole is back to the circular ring, so that the speed and the intensity of the gas sprayed out of the return air hole are maximum values, and the baffle plate can smoothly return to the initial position; the inlet diameter of the return air hole is large, so that the air inlet quantity of the return air hole is increased, and the outlet diameter of the return air hole is small, so that the flow speed of the gas sprayed out of the return air hole is high, and the adjusting effect of the return air hole is improved.

Preferably, a disc is arranged on the inner side wall of the air duct, more than two through holes are formed in the disc, a hose is arranged on one side, away from the circular ring, of each through hole, one end, away from the through holes, of each hose is fixedly connected with more than two spray heads through a branch pipe, and the spray heads connected with the same hose are circumferentially distributed on the inner side wall of the air duct; when the cooling device is used, air passing through the inner cavity of the air duct is gradually heated by the nodular iron castings, so that the cooling effect of the air is reduced, the cooling progress of the nodular iron castings in the air duct is inconsistent, and the overall progress is influenced; the disc is arranged, so that the air is divided into a plurality of parts when passing through the through holes on the disc, and the air of the plurality of parts is respectively led to different sections of the air cylinder by the hose and the fork tube and then is sprayed out from the spray head; the air that is shunted joins with the air that is heated at the middle section of dryer, has reduced the temperature of heated air to avoided leading to the cooling rate decline of the nodular cast iron spare in dryer middle section because of the air temperature is too high, and then guaranteed the whole cooling progress of nodular cast iron spare in the dryer.

Preferably, the spray head is arranged between the two baffle groups, the larger the distance value between the spray head and the ring is, the larger the diameter value of the through hole connected with the spray head is, and the through hole positioned in the center of the disc is not connected with the hose; when the device is used, the temperature of the nodular iron casting far away from the circular ring is slowly reduced because the air temperature far away from the circular ring is higher; through setting up the gradient with the diameter value of through-hole for the shower nozzle blowout a large amount of air far away from the ring, thereby guaranteed that the air temperature in the dryer is unanimous by a wide margin, and then guaranteed that the cooling progress of the nodular cast iron spare in the dryer is unanimous.

Preferably, a heat collection frame is fixed at one end, away from the circular ring, of the air duct, the heat collection frame is of a V-shaped structure, the heat collection frame is connected with the water absorption disc through a lead, the lead is inserted into the side wall of the outer ring of the water absorption disc, the outer ring of the water absorption disc is of a loose structure, and the diameter value of the water absorption disc is larger than the inner diameter value of the air duct; when the air cooling device is used, the water absorption efficiency of the water absorption disc is reduced because the water absorption disc absorbs water all the time, so that the work of the air cooling device is influenced; the heat collecting frame is arranged to absorb heat energy in heated air, and the heat energy is transferred to the water absorption disc through the conducting wire, so that the water absorption disc is heated and baked; the water absorption plate can be dehydrated and dried in the heating and baking processes, so that the water absorption plate can be continuously used, and the problem of failure of the water absorption plate is avoided; the outer ring of the water absorption disc is of a loose structure, so that water vapor generated when the water absorption disc is heated and dehydrated quickly enters air, and the dehydration performance of the water absorption disc is improved.

The invention has the following beneficial effects:

1. according to the heat treatment process for eliminating the ductile iron white cast defect, the air cooling device used in the process absorbs and filters moisture in air and heats the air entering the air duct, so that the air in contact with the ductile iron castings is dry and not low-temperature, the problems of deformation and cracking of the ductile iron castings possibly occurring in the air cooling process are avoided, and the heat treatment effect of the ductile iron castings is further ensured.

2. According to the heat treatment process for eliminating the ductile iron white cast defect, the air cooling device used in the process enables air to be continuously guided through the arrangement of the baffle plate, so that the air is in good contact with the ductile iron casting, and the air cooling effect is further improved.

3. According to the heat treatment process for eliminating the ductile iron white cast defect, the air cooling device used in the process is provided with the plurality of groups of spray heads, so that the temperature in the inner cavity of the air duct is kept approximately consistent, the cooling uniformity of ductile iron castings in the air duct is ensured, and the cooling efficiency is improved.

Drawings

The invention will be further explained with reference to the drawings.

FIG. 1 is a flow chart of the present invention;

FIG. 2 is a three-dimensional view of an air cooling device used in the present invention;

FIG. 3 is a schematic view showing the structure of an air cooling apparatus used in the present invention;

FIG. 4 is a schematic view showing the positional relationship between the baffle and the return air holes;

in the figure: the device comprises an air duct 1, a circular ring 2, a water absorption disc 3, an exhaust fan 4, a heating net 5, a guide rail 6, a placing frame 7, a baffle 8, an air return hole 9, an air collecting plate 10, a circular disc 11, a through hole 12, a spray head 13 and a heat collecting frame 14.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

As shown in fig. 1 to 4, the heat treatment process for eliminating the ductile iron white cast iron defects comprises the following steps:

s1: putting the nodular iron castings to be treated into a tempering furnace for heating, so that the temperature of the nodular iron castings is raised to the annealing temperature, the temperature rise time is ensured to be 2-4 hours, and the temperature is kept for 2-4 hours;

s2: gradually reducing the temperature of the tempering furnace in S1 to ensure that the ductile iron casting is cooled to 680-750 ℃ at the speed of 5-10 ℃/h and then cooled to 450-550 ℃ at the speed of 20-30 ℃/h;

s3: the method comprises the following steps of putting the nodular iron castings in S2 into an air cooling device for air cooling, wherein an exhaust fan 4 extracts air during air cooling to enter an air duct 1, a water absorption disc 3 filters water vapor in the air, a heating net 5 is used for regulating the temperature of the air entering the air duct 1 to enable the air entering the air duct 1 to be dry and at a proper temperature, the nodular iron castings are taken out after the air cooling is finished, the air cooling device absorbs and filters water in the air, the air entering the air duct 1 is heated to enable the air in contact with the nodular iron castings to be dry and not at a low temperature, and meanwhile a baffle 8 is used for guiding the air to enable the nodular iron castings to be in uniform contact with the air, so that the problems of deformation and cracking of the nodular iron castings possibly occurring during the air cooling process are avoided, and the heat treatment effect of the nodular iron castings is guaranteed;

the air cooling device used in the S3 comprises an air duct 1, wherein a ring 2 is fixed at one end of the air duct 1, a water absorption disc 3 is fixed on the inner side wall of the ring 2, the water absorption disc 3 is made of a water-absorbent resin material, an exhaust fan 4 is fixed at one end, close to the ring 2, of the inner cavity of the air duct 1, the exhaust fan 4 is used for extracting air, a heating net 5 is arranged on one side, away from the ring 2, of the exhaust fan 4, the heating net 5 is used for adjusting the temperature of the air entering the air duct 1, two guide rails 6 are arranged in the air duct 1, a placing frame 7 is movably mounted on the two guide rails 6, the placing frame 7 is of a net structure, and a controller is arranged on the air duct 1 and used for controlling the air cooling device to; when the air cooling device is used, in winter in the south, because the air humidity is high and the air temperature is low, the nodular iron castings are cooled unevenly during air cooling, so that the nodular iron castings are easy to deform or crack, and the production quality of the nodular iron castings is further influenced, and the problem is improved; when air cooling operation is carried out, the nodular iron castings are placed on the placing rack 7, then the placing rack 7 is pushed into the air duct 1, and meanwhile, the air cooling device is started; when the air cooling device is started, the exhaust fan 4 works, so that air is pumped into the air cylinder 1; before entering the air duct 1, the air needs to pass through the water absorption disc 3, and moisture in the air is absorbed when the air passes through the water absorption disc 3; the dried air enters the inner cavity of the air duct 1 and is heated by the heating net 5, so that the temperature of the air is adjusted; the processed air moves in the inner cavity of the air duct 1 and is blown out from one end of the air duct 1 far away from the exhaust fan 4; the nodular iron castings are contacted with the nodular iron castings in the air moving process, so that the nodular iron castings are in a normal air cooling environment, and normal air cooling is guaranteed; according to the invention, moisture in the air is absorbed and filtered, and the air entering the air duct 1 is heated, so that the air in contact with the nodular iron castings is dry and not at a low temperature, thereby avoiding the problems of deformation and cracking of the nodular iron castings possibly occurring in the air cooling process, and further ensuring the heat treatment effect of the nodular iron castings.

As a specific embodiment of the present invention, two or more baffle groups are equidistantly arranged on the inner side wall of the air duct 1 along the length direction thereof, each baffle group comprises two or more baffles 8 rotatably arranged along the circumferential direction of the air duct 1 at equal intervals, two or more air return holes 9 are arranged on the inner side wall of the air duct 1, the air return holes 9 correspond to the baffles 8 one by one, and an air collecting plate 10 is arranged at an inlet of each air return hole 9; when the cooling device is used, air moves transversely in the process of moving in the inner cavity of the air duct 1, and if the nodular iron castings are complex in shape or have cavities, the air cannot be in full contact with the nodular iron castings, so that the cooling speed and the cooling uniformity of the nodular iron castings are limited; by arranging the baffle 8, the baffle 8 can be contacted with the baffle 8 in the air moving process, so that the baffle 8 rotates; guiding air to the nodular iron castings in the rotating process of the baffle 8 to enable the nodular iron castings to be fully contacted with the air; after the baffle 8 rotates, the air moves to the position of the air collecting plate 10 beyond the baffle 8, the air enters the air return hole 9 after being guided by the air collecting plate 10, and the air entering the air return hole 9 moves to the outlet of the air return hole 9 to be blown out, so that the baffle 8 rotates reversely; the air is continuously guided through the baffle 8, so that the air is in good contact with the nodular iron castings, and the air cooling effect is improved.

As a specific embodiment of the present invention, the air return hole 9 is an annular structure, the air outlet direction of the air return hole 9 faces away from the direction of the circular ring 2, the side surface of the baffle 8 is a triangular structure, the outlet of the air return hole 9 is aligned with the top surface of the baffle 8, and the diameter value of the outlet of the air return hole 9 is smaller than the diameter value of the inlet thereof; when the air return device is used, the air outlet of the air return hole 9 faces the direction of the circular ring 2, so that air is easily fed from two ends of the air return hole 9, and the using effect of the air outlet is influenced; the outlet of the return air hole 9 is back to the circular ring 2, so that the speed and the intensity of the air sprayed out of the return air hole 9 are maximum values, and the baffle plate 8 can smoothly return to the initial position; the inlet diameter of the air return hole 9 is large, so that the air inlet amount of the air return hole 9 is increased, and the outlet diameter of the air return hole 9 is small, so that the flow speed of the gas sprayed out of the air return hole 9 is high, and the adjusting effect of the air return hole 9 is improved.

As a specific embodiment of the invention, a disc 11 is arranged on the inner side wall of the air duct 1, more than two through holes 12 are arranged on the disc 11, a hose is arranged on one side of each through hole 12, which is far away from the ring 2, one end of the hose, which is far away from the through holes 12, is fixedly connected with more than two nozzles 13 through a fork tube, and the nozzles 13 connected with the same hose are circumferentially distributed on the inner side wall of the air duct 1; when the cooling device is used, air passing through the inner cavity of the air duct 1 is gradually heated by the nodular iron castings, so that the cooling effect of the air is reduced, the cooling schedule of the nodular iron castings in the air duct 1 is inconsistent, and the overall schedule is influenced; by arranging the disc 11, the air is divided into a plurality of parts when passing through the through holes 12 on the disc 11, and the air of the plurality of parts is respectively led to different sections of the air duct 1 by the hose and the fork pipe and then is sprayed out from the spray head 13; the air that is shunted joins with the air that is heated at the middle section of dryer 1, has reduced the temperature of heated air to avoided leading to the cooling rate decline of the nodular iron casting in dryer 1 middle section because of the air temperature is too high, and then guaranteed the whole cooling progress of nodular iron casting in dryer 1.

As a specific embodiment of the present invention, the spray head 13 is installed between two baffle groups, the larger the distance value of the spray head 13 from the ring 2 is, the larger the diameter value of the through hole 12 connected with the spray head 13 is, and the through hole 12 located at the center of the disc 11 is not connected with a hose; when the device is used, the temperature of the nodular iron casting far away from the circular ring 2 is slowly reduced because the air temperature far away from the circular ring 2 is higher; the diameter value of the through hole 12 is set to be in a gradient mode, so that the spray head 13 far away from the circular ring 2 sprays a large amount of air, the air temperature in the air duct 1 is guaranteed to be consistent, and the cooling progress of the nodular iron castings in the air duct 1 is guaranteed to be consistent.

As a specific embodiment of the invention, a heat collecting rack 14 is fixed at one end of the air duct 1 far away from the circular ring 2, the heat collecting rack 14 is of a V-shaped structure, the heat collecting rack 14 is connected with the water absorbing disc 3 through a lead, the lead is inserted into the side wall of the outer ring of the water absorbing disc 3, the outer ring of the water absorbing disc 3 is of a loose structure, and the diameter value of the water absorbing disc 3 is greater than the inner diameter value of the air duct 1; when the air cooling device is used, the water absorption efficiency of the water absorption disc 3 is reduced because the water absorption disc 3 absorbs water all the time, so that the work of the air cooling device is influenced; the heat collecting rack 14 is arranged to absorb the heat energy in the heated air and transfer the heat energy to the water absorption disc 3 through the conducting wire, so that the water absorption disc 3 is heated and baked; the water absorption plate 3 can be dehydrated and dried in the heating and baking processes, so that the water absorption plate 3 can be continuously used, and the problem that the water absorption plate 3 is invalid is avoided; the outer ring of the water absorption disc 3 is of a loose structure, so that water vapor generated when the water absorption disc 3 is heated and dehydrated quickly enters air, and the dehydration performance of the water absorption disc 3 is improved.

When the air cooling device is used, in winter in the south, because the air humidity is high and the air temperature is low, the nodular iron castings are cooled unevenly during air cooling, so that the nodular iron castings are easy to deform or crack, and the production quality of the nodular iron castings is further influenced, and the problem is improved; when air cooling operation is carried out, the nodular iron castings are placed on the placing rack 7, then the placing rack 7 is pushed into the air duct 1, and meanwhile, the air cooling device is started; when the air cooling device is started, the exhaust fan 4 works, so that air is pumped into the air cylinder 1; before entering the air duct 1, the air needs to pass through the water absorption disc 3, and moisture in the air is absorbed when the air passes through the water absorption disc 3; the dried air enters the inner cavity of the air duct 1 and is heated by the heating net 5, so that the temperature of the air is adjusted; the processed air moves in the inner cavity of the air duct 1 and is blown out from one end of the air duct 1 far away from the exhaust fan 4; the nodular iron castings are contacted with the nodular iron castings in the air moving process, so that the nodular iron castings are in a normal air cooling environment, and normal air cooling is guaranteed; according to the invention, moisture in the air is absorbed and filtered, and the air entering the air duct 1 is heated, so that the air in contact with the nodular iron castings is dry and not low-temperature, thereby avoiding the problems of deformation and cracking of the nodular iron castings possibly occurring in the air cooling process, and further ensuring the heat treatment effect of the nodular iron castings; in addition, the air moves transversely in the moving process of the inner cavity of the air duct 1, and if the nodular iron castings are complex in shape or have cavities, the air cannot be in full contact with the nodular iron castings, so that the cooling speed and the cooling uniformity of the nodular iron castings are limited; by arranging the baffle 8, the baffle 8 can be contacted with the baffle 8 in the air moving process, so that the baffle 8 rotates; guiding air to the nodular iron castings in the rotating process of the baffle 8 to enable the nodular iron castings to be fully contacted with the air; after the baffle 8 rotates, the air moves to the position of the air collecting plate 10 beyond the baffle 8, the air enters the air return hole 9 after being guided by the air collecting plate 10, and the air entering the air return hole 9 moves to the outlet of the air return hole 9 to be blown out, so that the baffle 8 rotates reversely; when the baffle plate 8 rotates to the initial position, the inlet air at the air return hole 9 is blocked, so that the baffle plate 8 rotates forwards; the air is continuously guided through the baffle 8, so that the air is in good contact with the nodular iron castings, and the air cooling effect is improved.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.