CN118726736A - A ductile iron grinding ball quenching process method and equipment - Google Patents

Abstract

The invention discloses a ductile iron grinding ball quenching process method and equipment, and relates to the technical field of ductile iron grinding ball quenching, comprising the following steps: S1, pretreatment: performing one of annealing and normalizing treatment on the ductile iron grinding ball, and controlling the temperature and time; S2, heating: placing a blank in an alternating magnetic field to generate an induced current inside the blank, thereby generating Joule heat to heat the blank; in the invention, the organizational structure of the ductile iron grinding ball is adjusted and the internal stress is reduced through the pretreatment step, so as to prepare for the subsequent quenching process; the quenching process forms a martensitic structure of the ductile iron grinding ball through rapid cooling, which significantly improves its hardness and strength; the tempering treatment further eliminates the internal stress and brittleness generated in the quenching process, and improves the toughness of the material; the comprehensive effect of these steps makes the comprehensive mechanical properties of the ductile iron grinding ball significantly improved.

Description

A ductile iron grinding ball quenching process method and equipment

Technical Field

The invention relates to the technical field of quenching ductile iron grinding balls, in particular to a quenching process method and equipment for ductile iron grinding balls.

Background Art

Ductile iron grinding balls are a metal material with high strength, high toughness and excellent wear resistance, and are widely used in machinery manufacturing, automobile manufacturing, engineering machinery, agricultural machinery and equipment, etc. With the continuous advancement of industrial technology, the performance requirements for ductile iron grinding balls are getting higher and higher, especially in applications under high temperature, high pressure and complex working conditions, which poses a higher challenge to the hardness and toughness of ductile iron grinding balls.

The traditional quenching process of ductile iron grinding balls mainly relies on flame heating and simple quenching media. Although this process can improve the hardness and strength of ductile iron grinding balls to a certain extent, it often has problems such as uneven heating, unstable quenching effect, and easy environmental pollution. At the same time, the traditional quenching process does not accurately control the quenching temperature and time, which easily leads to cracking, deformation and other defects of ductile iron grinding balls during the quenching process, affecting their performance.

Therefore, it is necessary to improve and optimize the quenching process of ductile iron grinding balls to improve their performance stability and reliability. By adopting advanced heating methods, optimizing quenching media and quenching methods, it is possible to accurately control the organizational structure of ductile iron grinding balls, thereby improving their hardness and toughness and reducing the generation of defects.

The present invention patent is proposed in this context. By adopting advanced processes such as alternating magnetic field heating and segmented quenching, combined with special quenching media, efficient and accurate quenching of ductile iron grinding balls is achieved, thereby improving their performance and service life. At the same time, the present invention patent also provides corresponding quenching process equipment, providing hardware support for the realization of this process.

In summary, the invention is based on the problems and challenges in the prior art of quenching process of ductile iron grinding balls, and aims to improve the performance and service life of ductile iron grinding balls by improving and optimizing the quenching process, so as to meet the demand for high-performance metal materials in the industrial field.

Summary of the invention

The object of the present invention is to provide a ductile iron grinding ball quenching process method and equipment to solve the problems raised in the above background technology.

In order to solve the above technical problems, the present invention provides a ductile iron grinding ball quenching process method, comprising the following steps:

S1. Pretreatment: performing one of annealing and normalizing treatment on the ductile iron grinding balls, and controlling the temperature and time;

S2. Heating: placing the blank in an alternating magnetic field to generate an induced current inside it, thereby generating Joule heat to heat the blank;

S3, quenching: the heated ductile iron grinding balls are quickly placed in a quenching medium, and the ductile iron grinding balls are rapidly cooled to form a martensitic structure;

S4. Tempering: The ductile iron grinding balls are tempered after quenching to eliminate the internal stress and brittleness generated during the quenching process and further improve their toughness.

Furthermore, in S1, the annealing treatment adopts medium temperature annealing, the ductile iron grinding balls are heated to 780-880°C, and then kept warm for one hour for every 25 mm thick casting, and then slowly cooled to room temperature after a period of time.

Furthermore, in S1, the normalizing treatment is carried out at a high temperature, that is, the ductile iron grinding balls are heated to 850-950°C, kept at this temperature for a period of time, and then cooled to room temperature; the specific time of the holding time is calculated by a prediction formula, which is:

;

is the optimal holding time, d is the casting thickness, is a coefficient related to the casting thickness, c is the chemical composition of the casting, is a coefficient related to chemical composition, v is the heating rate, is a coefficient related to the heating rate, is the new constant term.

Further, in S3, the quenching medium is a quenching agent, and the quenching agent consists of water, salt and an organic additive.

Furthermore, in S3, in the quenching stage, a staged quenching method is adopted, that is, the ductile iron grinding balls are first heated to a certain temperature and then subjected to primary quenching, and then secondary heating and secondary quenching are performed.

Furthermore, it includes a mixing box, wherein a motor and a shell are respectively installed at the bottom and top of the mixing box, a driving end of the motor is installed with a cylinder rotatably connected to the mixing box, a plurality of stirring rods with equal spacing are installed on the outer wall of the cylinder, a plurality of first bevel gears are rotatably connected to the inner wall of the shell, a sleeve is rotatably connected to the top of the mixing box, a second bevel gear meshing with the first bevel gear is installed on the sleeve and the outer wall of the cylinder, an L-shaped scraper is installed on the outer wall of the sleeve, and a plurality of mixing rods are installed on the outer wall of the L-shaped scraper.

Furthermore, a through groove is provided on the top of the mixing box, the inner wall of the through groove is rotatably connected to the outer wall of the sleeve, and the top end of the cylinder is rotatably connected to the top of the shell.

Furthermore, a feed port is provided at the top of the mixing box, a funnel is installed between the inner bottom wall and the inner side wall of the mixing box, a discharge pipe is installed at the bottom of the mixing box, and a sealed bearing is provided between the barrel and the bottom of the mixing box.

Compared with the prior art, the present invention has the following beneficial effects:

Through the pretreatment steps, the organizational structure of the ductile iron grinding balls is adjusted, the internal stress is reduced, and preparation is made for the subsequent quenching process. The quenching process forms a martensitic structure of the ductile iron grinding balls through rapid cooling, which significantly improves their hardness and strength. The tempering treatment further eliminates the internal stress and brittleness generated during the quenching process and improves the toughness of the material. The combined effect of these steps has significantly improved the comprehensive mechanical properties of the ductile iron grinding balls.

This quenching process method provides a variety of treatment methods and parameter selections, including different treatment methods for annealing and normalizing, precise control of heating temperature, prediction formula calculation of holding time, special formulation of quenching medium and segmented quenching method. Flexible process selection and precise control means allow the quenching process to be fine-tuned according to specific needs and material properties, thereby achieving precise control of the performance of ductile iron grinding balls. At the same time, this also provides greater space for operation and optimization in actual production.

The barrel rotates with the driving end of the mixing box to drive the multiple stirring rods to rotate clockwise, and through the cooperation with the first bevel gear and the second bevel gear in the shell, it drives the L-shaped scraper on the sleeve to rotate counterclockwise, thereby making the multiple stirring rods and the multiple mixing rods rotate clockwise and counterclockwise respectively, thereby ensuring that the quenching agent in the mixing box is mixed more evenly. At the same time, the L-shaped scraper is used to facilitate the cleaning of the inner wall of the mixing box after use, so as to be used for subsequent mixing of the quenching agent, thereby ensuring the cooling effect of the quenching agent on the ductile iron grinding balls in step S3. The mixing box and the barrel are both made of transparent materials. When the barrel is not rotating, a lighting lamp is placed inside it, so as to facilitate relevant staff to observe the mixing progress of the quenching agent in the mixing box.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a flow chart of a ductile iron grinding ball quenching process according to the present invention;

FIG2 is a schematic cross-sectional view of a mixing box in a device for quenching ductile iron grinding balls according to the present invention;

FIG3 is a schematic diagram of the cross-sectional structure of a shell in a device for quenching ductile iron grinding balls according to the present invention.

FIG4 is a schematic diagram of the overall structure of a device for quenching ductile iron grinding balls according to the present invention:

1. Mixing box; 2. Motor; 3. Cylinder; 4. Stirring rod; 5. Shell; 6. First bevel gear; 7. Sleeve; 8. Second bevel gear; 9. L-shaped scraper; 10. Mixing rod; 11. Through slot; 12. Feed inlet; 13. Funnel; 14. Discharge pipe; 15. Sealed bearing.

DETAILED DESCRIPTION

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.

Please refer to Figures 1 to 4, the present invention provides a technical solution:

Referring to FIG. 1 , a ductile iron grinding ball quenching process method and equipment comprises the following steps:

S1. Pretreatment: annealing or normalizing the ductile iron grinding balls, and control the temperature and time to adjust their organizational structure, eliminate internal stress, and prepare for the subsequent quenching process; the annealing treatment is: put the ductile iron grinding balls into a heating furnace, heat them to a medium temperature range of 780-880℃, control the heating speed during the heating process to avoid uneven temperature distribution or excessive organizational changes caused by too fast or too slow heating, and calculate according to the thickness of the ductile iron grinding balls, according to the standard that every 25 mm thick casting needs to be kept warm for one hour.

For example, if the thickness of a ductile iron grinding ball is 100 mm, it needs to be kept warm for at least 4 hours. During the insulation process, the internal structure of the casting will gradually stabilize and the internal stress will be released. After the insulation is completed, the ductile iron grinding ball needs to be slowly cooled to room temperature. This step is to prevent excessive stress or deformation of the structure caused by excessive cooling. Usually, furnace cooling or air cooling can be used. Annealing can improve the plasticity and toughness of the casting, but the structure does not change significantly; normalizing treatment uses high temperature, that is, the ductile iron grinding ball is heated to 850-950℃, and then cooled to room temperature after a period of insulation; in order to more accurately predict the best insulation time of ductile iron grinding balls during normalizing treatment, the chemical composition, microstructure, heating rate and cooling method of the casting can be considered. Therefore, the specific insulation time is calculated by introducing a prediction formula with more influencing factors. The prediction formula is:

;

is the optimal holding time, d is the casting thickness, is a coefficient related to the casting thickness, c is the chemical composition of the casting (e.g. carbon content), is a coefficient related to chemical composition, v is the heating rate, is a coefficient related to the heating rate, is a new constant term; normalizing treatment can introduce a certain amount of martensite, thereby improving the hardness and strength of ductile iron grinding balls; through accurate holding time prediction, it can ensure that the castings achieve ideal organization and performance during the normalizing process, avoiding energy waste and extended production cycle caused by too long holding time; at the same time, it reduces the risk of substandard casting quality due to insufficient holding time, thereby improving overall production efficiency; accurate holding time prediction helps to ensure that the castings obtain uniform organization and performance during the normalizing process, avoiding organizational defects, performance fluctuations and other problems caused by improper holding time, and helps to improve the mechanical properties and corrosion resistance of the castings, thereby ensuring product quality and reliability; it can reduce unnecessary energy and material consumption, reduce production costs, and at the same time, reduce the scrap rate and rework rate caused by substandard casting quality, further reducing production costs; accurate holding time prediction makes the production process more controllable, reduces the impact of human factors and uncertainty on production results, helps to stabilize the production process, improve production efficiency and product quality, and reduces production risks.

S2. Heating: The induction heating equipment consists of an inductor, an electromagnet and an electronic oscillator that passes high-frequency alternating current through the electromagnet. The steps of induction heating are:

①. Prepare the workpiece: Place the ductile iron grinding ball workpiece to be quenched on the sensor;

②. Turn on the induction heating equipment: Start the induction heating equipment to make the inductor generate an alternating magnetic field;

③. Heating the workpiece: Under the action of the alternating magnetic field, the workpiece generates an induced current inside, which in turn generates heat, raising the temperature of the workpiece to the temperature required for quenching; induction heating can achieve rapid heating of the workpiece, and can even reach the required temperature in a short time, thereby improving production efficiency. Since induction heating generates heat inside the workpiece through the principle of electromagnetic induction, the heating is more uniform, reducing the temperature gradient and the risk of deformation and cracking of the workpiece. Induction heating does not require contact with an external heat source, which reduces heat loss, improves energy utilization efficiency, and reduces environmental pollution. Parameters such as the temperature and time of induction heating can be adjusted and controlled by the equipment, which facilitates the precise control of the quenching process;

S3, quenching: the heated ductile iron grinding balls are quickly placed in a quenching medium, and the ductile iron grinding balls are rapidly cooled to form a martensitic structure, thereby improving their hardness and strength;

S4. Tempering: After quenching, the ductile iron grinding balls are tempered to eliminate the internal stress and brittleness generated during the quenching process and further improve their toughness; specifically:

First of all, the tempering temperature range of ductile iron grinding balls is between 540℃ and 700℃. However, the specific tempering temperature should be determined according to the type, composition and desired properties of the material. For example, in some cases, in order to maintain the hardness and strength of the material, a slightly lower tempering temperature may be selected; in applications that require higher toughness, a slightly higher tempering temperature may be selected. In addition, the tempering time is also an important parameter, usually between 2 and 3 hours, that is, heat preservation. Too short tempering time may not be enough to fully eliminate internal stress, while too long tempering time may lead to excessive reduction in material properties.

It should be noted that excessively high tempering temperature may indeed lead to a decrease in material properties, such as a decrease in hardness and strength. Therefore, in actual operation, the tempering temperature should be strictly controlled to avoid exceeding the recommended tempering temperature range of the material; after the insulation is completed, the cooling rate should be controlled. Too fast cooling rate may cause new stress or cracks in the material, while too slow cooling rate may affect production efficiency. Therefore, the appropriate cooling method should be selected according to the characteristics of the material and process requirements, such as air cooling, wind cooling or furnace cooling; after tempering, some subsequent treatments can be carried out, such as shot blasting, etc., to remove surface impurities. After that, the performance of the ductile iron grinding balls should be checked to ensure that they meet the expected hardness and toughness requirements; in addition, since the tempering treatment involves high-temperature operation, the safety of the working environment should be ensured, and necessary protective measures should be taken to avoid burns or other safety accidents.

Further, in S3, the quenching medium is a quenching agent, which is composed of water, salt and organic additives; the salt in the quenching agent is used to increase the cooling rate, while the organic additives are used to adjust the cooling characteristics or improve the surface quality after quenching, ensuring that the quenching agent is mixed evenly to obtain a stable cooling effect, and ensuring that the ductile iron grinding balls are completely immersed in the quenching agent to achieve a uniform cooling effect; through this quenching process method, the surface hardness of the ductile iron grinding balls reaches above HRC60, the core hardness reaches above HRC55, and the impact toughness is significantly improved.

Furthermore, in S3, in the quenching stage, a segmented quenching method is adopted, that is, the ductile iron grinding balls are first heated to a certain temperature and then subjected to primary quenching, and then secondary heating and secondary quenching are performed; the segmented quenching method can further improve the hardness and uniformity of the ductile iron grinding balls. This quenching process method significantly improves the wear resistance of the ductile iron grinding balls and extends their service life; specifically: first, the ductile iron grinding balls are placed in a heating device and heated to a predetermined temperature for the primary quenching, which is usually lower than the final quenching temperature, in order to transform part of the structure of the ductile iron grinding balls while avoiding excessive influence of excessive temperature on the materials.

When the ductile iron grinding ball is heated to the predetermined temperature, it is quickly taken out and placed in the quenching medium for the first quenching. The purpose of the first quenching is to preliminarily harden the structure of the ductile iron grinding ball and prepare for the subsequent second quenching. After the first quenching is completed, the ductile iron grinding ball is taken out and necessary inspection and preparation are carried out, and then the second heating stage is entered. The purpose of the second heating is to further homogenize the structure of the ductile iron grinding ball and eliminate the residual stress and structural inhomogeneity that may be generated by the first quenching. During the second heating process, the heating temperature and heating time need to be strictly controlled to ensure that the structure of the ductile iron grinding ball can be evenly transformed, while avoiding excessive heating to cause the material performance to deteriorate. When the ductile iron grinding ball is heated to the predetermined temperature for the second quenching, it is quickly taken out again and placed in the quenching medium for the second quenching. The cooling rate and medium selection of the second quenching should be determined according to the material and performance requirements of the ductile iron grinding ball to ensure the best hardening effect and structural uniformity. After the second quenching is completed, the ductile iron grinding ball may have higher hardness and brittleness.

In order to eliminate residual stress and improve toughness, the ductile iron grinding balls need to be tempered. The selection of tempering temperature and time should be determined according to the material and performance requirements of the ductile iron grinding balls to achieve an ideal balance of hardness, strength and toughness. It should be added that in order to ensure the stability and repeatability of the quenching process, the entire process needs to be monitored and key parameters recorded. For example, temperature sensors are used to monitor the temperature of the ductile iron grinding balls in real time, and timers are used to control the heating and holding time. These records are not only helpful in analyzing the quenching effect, but also can provide a basis for subsequent process optimization.

Referring to Figures 2 to 4, a device for quenching ductile iron grinding balls includes a mixing box 1, a motor 2 and a shell 5 are respectively installed at the bottom and top of the mixing box 1, a barrel 3 rotatably connected to the mixing box 1 is installed at the driving end of the motor 2, a plurality of stirring rods 4 with equal spacing are installed on the outer wall of the barrel 3, a plurality of first bevel gears 6 are rotatably connected to the inner wall of the shell 5, a sleeve 7 sleeved on the outside of the barrel 3 is rotatably connected to the top of the mixing box 1, a second bevel gear 8 meshingly connected to the first bevel gear 6 is installed on the sleeve 7 and the outer wall of the barrel 3, a bottom of one of the second bevel gears 8 is rotatably connected to the top of the mixing box 1, an L-shaped scraper 9 is installed on the outer wall of the sleeve 7, and a plurality of mixing rods 10 are installed on the outer wall of the L-shaped scraper 9.

Furthermore, a through groove 11 is provided at the top of the mixing box 1, and the inner wall of the through groove 11 is rotatably connected to the outer wall of the sleeve 7, and the top of the cylinder 3 is rotatably connected to the top of the shell 5; by providing the through groove 11, the sleeve 7 is rotatably connected to the top of the mixing box 1, and the top of the cylinder 3 is rotatably connected to the top of the shell 5, so as to avoid affecting the rotation of the cylinder 3; a feed port 12 is provided at the top of the mixing box 1, a funnel 13 is installed between the inner bottom wall and the inner side wall of the mixing box 1, a discharge pipe 14 is installed at the bottom of the mixing box 1, and a sealed bearing 15 is provided between the cylinder 3 and the bottom of the mixing box 1;

By setting the feed inlet 12, the quenching agent composed of water, salt and organic additives in S3 is supplied to enter the mixing box 1. By setting the funnel 13 and utilizing the discharge pipe 14, the mixed quenching agent in the mixing box 1 is discharged. By setting the sealing bearing 15, not only the rotation of the cylinder 3 is made more stable, but also the sealing between the mixing box 1 and the cylinder 3 is ensured. The bottom of the mixing box 1 is equipped with a support leg for supporting the mixing box 1. The support leg increases the height of the mixing box 1 and is convenient for installing the motor 2. A fixing seat is installed between the motor 2 and the bottom of the mixing box 1. By setting the fixing seat, not only the motor 2 is conveniently installed on the bottom of the mixing box 1, but also the motor 2 is more stable during operation. A valve is installed at the bottom of the discharge pipe 14 for controlling the flow of the quenching agent passing through the discharge pipe 14.

The barrel 3 rotates with the driving end of the mixing box 1 and drives the multiple stirring rods 4 to rotate clockwise, and through the cooperation with the first bevel gear 6 and the second bevel gear 8 in the shell 5, it drives the L-shaped scraper 9 on the sleeve 7 to rotate counterclockwise, thereby making the multiple stirring rods 4 and the multiple mixing rods 10 rotate clockwise and counterclockwise respectively, thereby ensuring that the quenching agent in the mixing box 1 is mixed more evenly. At the same time, the L-shaped scraper 9 is used to facilitate the cleaning of the inner wall of the mixing box 1 after use, so as to facilitate the subsequent mixing of the quenching agent, thereby ensuring the cooling effect of the quenching agent on the ductile iron grinding balls in step S3. The mixing box 1 and the barrel 3 are both made of transparent materials. When the barrel 3 is not rotating, a lighting lamp is placed inside it, so as to facilitate relevant staff to observe the mixing progress of the quenching agent in the mixing box 1.

Working principle:

The barrel 3 rotates with the driving end of the mixing box 1 and drives the multiple stirring rods 4 to rotate clockwise, and through the cooperation with the first bevel gear 6 and the second bevel gear 8 in the shell 5, it drives the L-shaped scraper 9 on the sleeve 7 to rotate counterclockwise, thereby making the multiple stirring rods 4 and the multiple mixing rods 10 rotate clockwise and counterclockwise respectively, thereby ensuring that the quenching agent in the mixing box 1 is mixed more evenly. At the same time, the L-shaped scraper 9 is used to facilitate the cleaning of the inner wall of the mixing box 1 after use, so as to facilitate the subsequent mixing of the quenching agent, thereby ensuring the cooling effect of the quenching agent on the ductile iron grinding balls in step S3. The mixing box 1 and the barrel 3 are both made of transparent materials. When the barrel 3 is not rotating, a lighting lamp is placed inside it, so as to facilitate relevant staff to observe the mixing progress of the quenching agent in the mixing box 1.

Claims (8)

1. A quenching process method for a spheroidal graphite cast iron grinding ball is characterized by comprising the following steps of: the method comprises the following steps:

S1, pretreatment: one of annealing and normalizing the spheroidal graphite cast iron grinding ball, and controlling the temperature and time;

s2, heating: placing the blank in an alternating magnetic field to generate induced current in the blank so as to generate joule heat to heat the blank;

s3, quenching: rapidly placing the heated spheroidal graphite cast iron grinding ball into a quenching medium, and rapidly cooling to form a martensitic structure;

S4, tempering: tempering the quenched ductile cast iron grinding ball to eliminate internal stress and brittleness generated in the quenching process and further improve the toughness of the ductile cast iron grinding ball.

2. The process for quenching spheroidal graphite cast iron grinding balls according to claim 1, wherein the process comprises the following steps: in S1, the annealing treatment adopts medium-temperature annealing, the spheroidal graphite cast iron grinding ball is heated to 780-880 ℃, then the spheroidal graphite cast iron grinding ball is subjected to heat preservation for one hour according to the standard of casting with the thickness of 25mm, and the spheroidal graphite cast iron grinding ball is slowly cooled to room temperature after being subjected to heat preservation for a period of time.

3. The process for quenching spheroidal graphite cast iron grinding balls according to claim 1, wherein the process comprises the following steps: in S1, the normalizing treatment adopts high temperature, namely, the spheroidal graphite cast iron grinding ball is heated to 850-950 ℃, and is cooled to room temperature after heat preservation for a period of time; the specific time of heat preservation is calculated through a prediction formula, wherein the prediction formula is as follows:

×d＋×c＋×v＋；

Is the optimal heat preservation time, d is the thickness of the casting, Is a coefficient related to the thickness of the casting, c is the chemical composition of the casting,Is a coefficient related to chemical composition, v is a heating rate,Is a coefficient related to the heating rate,Is a new constant term.

4. The process for quenching spheroidal graphite cast iron grinding balls according to claim 1, wherein the process comprises the following steps: in S3, the quenching medium is a quenching agent, and the quenching agent consists of water, salt and organic additives.

5. The process for quenching spheroidal graphite cast iron grinding balls according to claim 1, wherein the process comprises the following steps: in S3, in the quenching stage, a sectional quenching mode is adopted, namely, the spheroidal graphite cast iron grinding ball is firstly heated to a certain temperature and then subjected to primary quenching, and then secondary heating and secondary quenching are carried out.

6. The utility model provides a nodular cast iron grinding ball quenching's equipment which characterized in that: including mixing box (1), motor (2) and casing (5) are installed respectively to the bottom and the top of mixing box (1), barrel (3) that rotates with mixing box (1) are connected are installed to the drive end of motor (2), a plurality of equidistant puddlers (4) are installed to the outer wall of barrel (3), casing (5) inner wall rotates and is connected with a plurality of first bevel gears (6), the top of mixing box (1) rotates and is connected with sleeve pipe (7) of cover establishing the outside at barrel (3), second bevel gear (8) that is connected with first bevel gear (6) meshing are all installed to the outer wall of sleeve pipe (7) and barrel (3), L shape doctor bar (9) are installed to the outer wall of sleeve pipe (7), a plurality of hybrid bars (10) are installed to the outer wall of L shape doctor bar (9).

7. An apparatus for quenching a spheroidal graphite cast iron grinding ball according to claim 6 wherein: the top of mixing box (1) has seted up logical groove (11), the inner wall of logical groove (11) is connected with the outer wall rotation of sleeve pipe (7), the top of barrel (3) is connected with the top rotation of casing (5).

8. An apparatus for quenching a spheroidal graphite cast iron grinding ball according to claim 7 wherein: the top of mixing box (1) has seted up feed inlet (12), install funnel (13) between interior bottom wall and the inside wall of mixing box (1), discharging pipe (14) are installed to the bottom of mixing box (1), be provided with sealed bearing (15) between the bottom of barrel (3) and mixing box (1).