High-performance steel shot steel sand preparation process and preparation device

Abstract

The application discloses a high-performance steel shot steel sand preparation process and a preparation device, and particularly relates to the technical field of metal abrasives. The preparation process comprises the following steps: S1, weighing and batching raw materials, and then smelting by using an electric furnace to obtain a molten steel; S2, refining and argon blowing of the molten steel to reduce the content of dissolved gas (such as hydrogen, nitrogen and oxygen) in the molten steel, and remove residual non-metallic inclusions in the molten steel; S3, pouring the molten steel in S2 into a tundish and granulating by using a centrifugal granulator to obtain semi-finished metal abrasives; S4, drying the semi-finished metal abrasives; S5, quenching the dried abrasives in S4 to a hardness of more than HRC60; S6, drying the quenched material in S5 and then crushing; S7, tempering the crushed material in S6 or the quenched material in S5 to obtain corresponding steel sand steel shots; and S8, screening to obtain high-performance steel sand steel shots with required particle sizes. The prepared metal steel sand steel shots have less quenching cracks, uniform hardness and good impact fatigue resistance.

Description

Technical Field

[0001] This invention relates to the field of metal abrasive technology, specifically to a process and apparatus for preparing high-performance steel shot and grit. Background Technology

[0002] Sandblasting is a surface treatment process that uses compressed air to accelerate sand particles, causing them to impact the workpiece surface at high speed to remove oxide scale, rust, and impurities, thus achieving surface cleaning. Compared with traditional manual and power-driven cleaning, sandblasting offers better cleaning quality and speed. Compared with pickling, it is more environmentally friendly, produces less pollution, and is easier to control. After cleaning, it can create a certain roughness on the steel surface, improving the adhesion between the coating and the steel surface. Compared with shot blasting, it is more flexible in direction, allowing the spray gun to be pointed at any area that needs cleaning. Compared with shot blasting, it has higher cleaning efficiency, and the surface area per unit area of ​​the steel is larger, resulting in a stronger bond between the coating and the steel surface.

[0003] Abrasives used for sandblasting can be divided into non-metallic abrasives and metallic abrasives. Non-metallic abrasives have an extremely high breakage rate during use, generating a large amount of dust, causing serious pollution, and have low cleaning efficiency. Therefore, except for a few that are still in use, most non-metallic abrasives have been replaced by metallic abrasives. The most common metallic abrasives are bearing steel grit and high-carbon cast steel grit, but because commonly used bearing steel grit and high-carbon steel grit have high hardness and brittleness, their overall lifespan is not good.

[0004] To address these issues, we propose a high-performance steel shot and grit preparation process and apparatus. Summary of the Invention

[0005] The purpose of this invention is to provide a high-performance steel shot and grit preparation process and apparatus to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-performance steel shot / grit preparation process, the preparation process comprising the following steps:

[0007] S1. After weighing and batching the raw materials, the steel is smelted in an electric furnace to obtain molten steel.

[0008] S2. Refine the molten steel by blowing argon to reduce the content of dissolved gases (such as hydrogen, nitrogen, and oxygen) in the molten steel; remove residual non-metallic inclusions in the molten steel.

[0009] S3. Pour the molten steel from S2 into an intermediate ladle and granulate it using a centrifugal granulator to obtain a semi-finished metal abrasive.

[0010] S4. Dry the semi-finished metal abrasive;

[0011] S5. Quench the dried abrasive from S4 to a hardness of HRC60 or higher.

[0012] S6. After drying the quenched material in S5, crush it.

[0013] S7. Temper the crushed material in S6 or the quenched material in S5 to obtain the corresponding steel shot and steel grit.

[0014] S8. Screening to obtain high-performance steel shot and grit of the required particle size.

[0015] Preferably, the quenching temperature in step S5 is 920-1000℃, the quenching medium in S5 is a molten liquid salt bath of nitrate solution / mixture, and the quenching time in S5 is 2 hours.

[0016] Preferably, the quenching medium in step S5 is dinitrate water;

[0017] That is, by mass percentage: 25% NaNO3 + 25% NaNO2 + 50% water, operating temperature < 60℃.

[0018] The present invention also provides a high-performance steel shot and grit preparation apparatus, which includes a quenching mechanism;

[0019] The quenching mechanism includes a feeding bin, a continuous quenching furnace, a furnace liner, a quenching furnace outlet, an annular water ring, a quenching water tank, and a quenching material outlet.

[0020] One end of the continuous quenching furnace is provided with a feeding hopper, the inside of the continuous quenching furnace has a rotatable furnace liner, and the other end of the continuous quenching furnace is provided with an annular water ring and a quenching water tank from top to bottom.

[0021] The discharge port of the feeding hopper is connected to the feed port of the continuous quenching furnace. The continuous quenching furnace is located directly above the annular water ring and has a quenching furnace discharge port. The quenching furnace discharge port is connected to the middle of the annular water ring. The annular water ring is connected to the quenching water tank. The quenching material outlet is located on the side of the bottom of the quenching water tank.

[0022] Preferably, the annular water ring has an annular water ring inlet on its outer side, and the annular water ring inlet is connected to the interior of the annular water ring;

[0023] The inner circumference of the annular water ring is equipped with annular water ring nozzles, and the annular water ring nozzles are connected to the annular water ring.

[0024] Preferably, the device further includes a steel shot crushing and screening mechanism;

[0025] The steel shot crushing and screening mechanism includes a steel structure platform, a hoist, a feed hopper, a crusher assembly, a sorting belt, a vibrating screen mechanism, and a conveyor belt assembly;

[0026] The feed hopper is installed on the top of the steel structure platform, the crusher assembly is installed on the top of the steel structure platform, the discharge port of the feed hopper is connected to the feed port of the crusher assembly, the sorting belt is inclined and set at the bottom of the steel structure platform, and the vibrating screen mechanism is set directly below the discharge port of the sorting belt.

[0027] The vibrating screen mechanism includes a screen assembly, a return hopper assembly, and a discharge baffle.

[0028] The discharge baffle and screen components are located at opposite ends of the return bin component. The return bin component is located directly below the sorting belt. The lower end of the sorting belt is located diagonally above the discharge baffle, and the upper end of the sorting belt is located diagonally above the screen component.

[0029] A hoist is installed through the middle of the steel structure platform. The discharge port of the hoist is connected to the feeding bin. The return bin component is connected to the hoist. The conveyor belt assembly is located directly below the screen component.

[0030] Preferably, a return material rack is installed at the bottom of the steel structure platform. The return material rack is located on both sides of the screen component, the return material bin component, and the discharge baffle. A circulation loop is formed between the return material rack and the end of the screen component. The circulation loop passes through the bottom of the conveyor belt assembly and is connected to the elevator.

[0031] Preferably, the vibrating screen mechanism further includes a vibrator and a vibrating platform;

[0032] The vibration platform is located directly below the material discharge baffle, the vibrator is installed on the top of the vibration platform, and the vibration platform is connected to the bottom of the material discharge baffle.

[0033] Preferably, the crusher assembly includes a frame, a discharge hopper, and crushing rollers;

[0034] The frame is installed on top of the steel structure platform, the crushing rollers are arranged inside the frame with relative rotation, and the discharge hopper is installed at the discharge port at the bottom of the frame, with the discharge port of the discharge hopper located above the lower end of the sorting belt.

[0035] The elevator includes a horizontal guide chute, a horizontal conveying auger, a vertical guide cylinder, a vertical conveying auger, and a discharge port;

[0036] The horizontal guide chute is connected to the discharge port and circulation loop of the return hopper component. The horizontal conveying augers are rotatably installed at both ends inside the horizontal guide chute. A vertical guide cylinder is installed in the middle of the horizontal guide chute. The vertical conveying auger is rotatably installed inside the vertical guide cylinder. The top of the vertical guide cylinder penetrates the top of the steel structure platform and is provided with a discharge port. The discharge port is located directly above the feed hopper.

[0037] Preferably, the two sides of the return rack are bolted to a side frame, an adjustment frame is provided on the inner side of the side frame, a sorting roller is rotatably connected to the inner side of the adjustment frame, and the sorting belt is sleeved on the outer side of the sorting roller.

[0038] The two ends of the sorting roller at the lower end of the sorting belt pass through the adjustment frame and are rotatably connected to the side frame. The adjustment frame is equipped with a threaded column on the outer side at the upper end of the sorting belt. The side frame is provided with an arc-shaped slide groove. The threaded column is slidably disposed in the arc-shaped slide groove. The threaded column extends out of the arc-shaped slide groove and is threadedly connected to a nut. The nut contacts the outer side of the side frame.

[0039] A servo motor three is mounted on the outer side of the side frame, and the output shaft of the servo motor three is connected to the end of the sorting roller located at the lower end of the sorting belt.

[0040] A servo motor is installed at the end of the transverse guide chute, and the output shaft of the servo motor is connected to the transverse conveying auger.

[0041] A second servo motor is installed at the top of the vertical guide cylinder, and the output shaft of the second servo motor is connected to the vertical conveying auger.

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0043] 1. The high-performance steel shot and grit produced by this invention, after being centrifuged and granulated into pellets and cooled to room temperature, have less lamellar martensite structure, fewer cracks, better toughness, and a longer Owen fatigue life than conventional high-carbon steel shot and grit and bearing steel shot.

[0044] 2. Through specific heat treatment, steel shot and grit are made into a carbide-free bainitic structure and a lath-shaped pre-generated martensite structure with strip-shaped retained austenite, giving the steel shot and grit good impact fatigue resistance.

[0045] 3. By passing through a sorting belt before screening, the proportion of defective steel shot in the steel shot is reduced, while the uniformity of steel shot particle size is improved, resulting in steel shot sprayed workpieces with greater roughness and higher fatigue resistance. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a schematic diagram of the process flow of the present invention;

[0048] Figure 2 This is a schematic diagram of the quenching mechanism in this invention;

[0049] Figure 3 This is a schematic diagram of the structure of the annular water ring nozzle in this invention;

[0050] Figure 4 This is a front view of the steel shot crushing and screening mechanism in this invention.

[0051] Figure 5 This is a top view of the steel shot crushing and screening mechanism in this invention.

[0052] Figure 6 This is a cross-sectional schematic diagram of the steel shot crushing and screening mechanism in this invention;

[0053] Figure 7 This is a schematic diagram of the cross-sectional view of the crusher assembly connection in this invention;

[0054] Figure 8 This is another cross-sectional view of the steel shot crushing and screening mechanism in this invention.

[0055] Figure 9 This is a schematic diagram of the adjustment frame connection in this invention.

[0056] In the diagram: 100, quenching mechanism;

[0057] 101. Feed hopper; 102. Continuous quenching furnace; 103. Furnace liner; 104. Quenching furnace outlet; 105. Annular water ring; 106. Quenching water tank; 107. Quenching material outlet; 108. Annular water ring nozzle; 109. Annular water ring inlet;

[0058] 200. Steel grit crushing and screening mechanism;

[0059] 1. Steel structure platform;

[0060] 2. Elevator; 21. Servo Motor 1; 22. Horizontal Guide Chute; 23. Horizontal Conveying Screw; 24. Vertical Guide Cylinder; 25. Vertical Conveying Screw; 26. Servo Motor 2; 27. Discharge Port;

[0061] 3. Feed hopper;

[0062] 4. Crusher components; 41. Frame; 42. Discharge hopper; 43. Crushing rollers;

[0063] 51. Sorting belt; 52. Sorting roller; 53. Side frame; 54. Adjusting frame; 55. Servo motor three; 56. Threaded column;

[0064] 6. Vibrating screen mechanism; 61. Screen assembly; 62. Return hopper assembly; 63. Discharge baffle; 64. Vibrator; 65. Vibrating platform;

[0065] 7. Conveyor belt assembly;

[0066] 8. Return rack. Detailed Implementation

[0067] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0068] like Figure 1 As shown, the present invention provides a process for preparing high-performance steel shot and grit;

[0069] Its preparation method:

[0070] S1. After weighing and batching the raw materials, the steel is smelted in an electric furnace to obtain molten steel.

[0071] S2. Refine the molten steel by blowing argon to reduce the content of dissolved gases (such as hydrogen, nitrogen, and oxygen) in the molten steel; remove residual non-metallic inclusions in the molten steel.

[0072] S3. Pour the molten steel from S2 into an intermediate ladle and granulate it using a centrifugal granulator to obtain a semi-finished metal abrasive.

[0073] S4. Dry the semi-finished metal abrasive;

[0074] S5. Quench the dried abrasive from S4 to a hardness of HRC60 or higher.

[0075] S6. After drying the quenched material in S5, crush it.

[0076] S7. Temper the crushed material in S6 or the quenched material in S5 to obtain the corresponding steel shot and steel grit.

[0077] S8. Screening to obtain high-performance steel shot and grit of the required particle size.

[0078] In this embodiment, the quenching temperature in step S5 is 920°C, the quenching medium in S5 is a molten liquid salt bath of nitrate solution / mixture, and the quenching time in S5 is 2 hours, so that some of the supercooled austenite is transformed into carbide-free bainite.

[0079] In this embodiment, the quenching medium in step S5 is dinitrate water;

[0080] That is, by mass percentage: 25% NaNO3 + 25% NaNO2 + 50% water, operating temperature < 60℃.

[0081] It should be noted that, in the above embodiments, the high-performance steel shot and grit produced by the present invention, after centrifugal granulation and cooling to room temperature, exhibits less lamellar martensite structure, fewer cracks, and better toughness. Its Owen fatigue life is longer than that of conventional high-carbon steel shot and grit and bearing steel shot. Specific heat treatment results in a carbide-free bainitic structure and a lamellar pre-generated martensite structure with lamellar retained austenite, giving the steel shot and grit excellent impact fatigue resistance. The hardness can be controlled within a deviation of no more than 6 HRC. The uniformity of hardness improves product quality and avoids the formation of lamellar steel shot particles during breakage, resulting in a fuller overall structure and stronger resistance to breakage.

[0082] Figure 2-3 As shown, the present invention also provides a high-performance steel shot and grit preparation device for the quenching process in step S5 of the above preparation process, the device including a quenching mechanism 100.

[0083] The quenching mechanism 100 includes a feeding bin 101, a continuous quenching furnace 102, a furnace liner 103, a quenching furnace outlet 104, an annular water ring 105, a quenching water tank 106, and a quenching material outlet 107.

[0084] One end of the continuous quenching furnace 102 is provided with a feeding bin 101, the continuous quenching furnace 102 has a rotatable furnace liner 103 inside, and the other end of the continuous quenching furnace 102 is provided with an annular water ring 105 and a quenching water tank 106 from top to bottom.

[0085] The discharge port of the feed hopper 101 is connected to the feed port of the continuous quenching furnace 102. The continuous quenching furnace 102 is located directly above the annular water ring 105 and has a quenching furnace discharge port 104. The quenching furnace discharge port 104 is connected to the middle of the annular water ring 105. The annular water ring 105 is connected to the quenching water tank 106. The quenching material outlet 107 is provided on the side of the bottom end of the quenching water tank 106.

[0086] In this embodiment, an annular water ring 105 is provided with an annular water ring inlet 109 on its outer side, and the annular water ring inlet 109 is connected to the interior of the annular water ring 105.

[0087] The inner circumferential array of the annular water ring 105 is provided with annular water ring nozzles 108, and the annular water ring nozzles 108 are connected to the annular water ring 105.

[0088] It should be noted that the dried abrasive is heated inside the furnace chamber 103. The continuous quenching furnace 102 and the furnace chamber 103 are inclined downwards from the feed hopper 101 to the quenching furnace outlet 104, so that the heated abrasive can gradually move towards the quenching furnace outlet 104. The steel shot and grit are quenched and cooled in the annular water ring 105. The quenched material comes into contact with the cooling water from all directions, the cooling rate is relatively uniform, and the quenching hardness is relatively uniform. At the same time as quenching and cooling, the high-pressure water will disperse the sticky molten steel. The initially cooled steel shot and grit fall into the quenching water tank 106 under the annular water ring 105, and gradually cool and solidify before entering the next process.

[0089] The specific process is as follows: First, abrasive is added through the feed hopper 101. Then, the abrasive enters the furnace chamber 103 from the outlet of the feed hopper 101. Under the action of the rotation of the furnace chamber 103, the abrasive is prevented from accumulating and the abrasive is heated more evenly. Then, the quenching material falls from the outlet 104 of the quenching furnace and passes through the middle of the annular water ring 105. The quenching medium is injected into the annular water ring 105 through the inlet 109 and then sprayed out from the water nozzle 108 of the annular water ring to form high-pressure water, which quenches the quenching material relatively comprehensively. Then, it falls into the quenching water tank 106 for cooling and shaping, and is discharged from the quenching material outlet 107. The hardness deviation of the prepared cast steel shot does not exceed 6HRC. The subsequent crushing and shaping is good, the particles are full, and the steel shot has good performance.

[0090] Based on the above, this embodiment provides a steel shot and steel grit produced by the above preparation process, which, by mass percentage, contains the following components: C 0.08-1.2%, Si 0.4-2.0%, Mn 0.35-1.2%, Cr 0.10-0.6%, S 0-0.03%, P 0-0.03%, Al 0.02-0.10%, Ni 0.05-0.20%, Mo 0.01-0.10%, V 0.05-0.15%, Nb 0.02-0.10%, with the remainder being Fe and unavoidable impurities;

[0091] The metallic steel shot and grit prepared by this invention have fewer quenching cracks, a carbide-free bainitic structure and a lath-shaped pre-generated martensite structure with strip-shaped retained austenite, uniform hardness, fewer secondary crushing cracks, and good impact fatigue resistance.

[0092] like Figure 3-9 As shown, the present invention also provides a high-performance steel shot and grit preparation device for the crushing and screening process in steps S6, 7, and 8 of the above preparation process. The device also includes a steel shot crushing and screening mechanism 200.

[0093] The steel shot crushing and screening mechanism 200 includes a steel structure platform 1, an elevator 2, a feed bin 3, a crusher assembly 4, a sorting belt 51, a vibrating screen mechanism 6, and a conveyor belt assembly 7.

[0094] The feeding bin 3 is installed on the top of the steel structure platform 1, the crusher assembly 4 is installed on the top of the steel structure platform 1, the discharge port of the feeding bin 3 is connected to the inlet of the crusher assembly 4, the sorting belt 51 is inclinedly arranged at the bottom of the steel structure platform 1, and the vibrating screen mechanism 6 is arranged directly below the discharge port of the sorting belt 51.

[0095] The vibrating screen mechanism 6 includes a screen component 61, a return bin component 62, and a discharge baffle 63;

[0096] The discharge baffle 63 and the screen component 61 are respectively located at both ends of the return bin component 62. The return bin component 62 is located directly below the sorting belt 51. The lower end of the sorting belt 51 is located diagonally above the discharge baffle 63, and the upper end of the sorting belt 51 is located diagonally above the screen component 61.

[0097] A hoist 2 is installed through the middle of the steel structure platform 1. The discharge port of the hoist 2 is connected to the feeding bin 3. The return bin component 62 is connected to the hoist 2. The conveyor belt assembly 7 is located directly below the screen component 61.

[0098] It should be noted that in this embodiment, the dried quenched material is conveyed to the inside of the crusher assembly 4 through the feed hopper 3 for crushing. The discharge port of the feed hopper 3 and the feed port of the crusher assembly 4 are inclined downwards. Therefore, under the guidance of its structure, the quenched material can be smoothly fed. The steel shot crushed by the crusher assembly 4 falls onto the sorting belt 51. Since the sorting belt 51 has an adjustable inclination angle, and the steel shot has sharp edges and a large angle of repose, it will be conveyed along with the sorting belt 51. The sorting belt 51 distributes the steel shot relatively evenly into the vibrating screen mechanism 6. After the vibrating screen mechanism 6 screens the steel shot, the steel shot that meets the particle size requirements falls to the conveyor belt assembly 7 to enter the next process. The steel shot that does not meet the particle size requirements is returned to the elevator 2 by the vibrating screen mechanism 6. The steel shot that is not crushed in the steel shot has a small angle of repose and does not follow the sorting belt 51 but slides out from the lower end of the sorting belt 51 into the elevator 2. After being lifted by the elevator 2, it enters the feeding bin 3 for further crushing, and so on.

[0099] The vibrating screen mechanism 6 gradually tilts downward from the discharge baffle 63 towards the screen component 61, so that the vibration of the vibrating screen mechanism 6 can make the steel shot move forward, so that the steel shot can enter the elevator 2 through the return bin component 62. The steel shot that meets the particle size is screened at the screen component 61 and falls onto the conveyor belt assembly 7.

[0100] Furthermore, a return material rack 8 is installed at the bottom of the steel structure platform 1. The return material rack 8 is located on both sides of the screen component 61, the return material bin component 62, and the drop baffle 63. A circulation loop is formed between the return material rack 8 and the end of the screen component 61. The circulation loop passes through the bottom of the conveyor belt assembly 7 and is connected to the elevator 2.

[0101] It should be noted that in this embodiment, the shielding of the return frame 8 can effectively prevent the steel shot and grit on the vibrating screen mechanism 6 from falling off, and under the guidance of the circulation loop formed by the return frame 8, the steel shot and grit that do not meet the particle size can enter the elevator 2.

[0102] The sorting belt 51 separates the unbroken steel shot from the steel grit, preventing steel shot from entering the screen component 61. This reduces the steel shot content in the steel grit product to no more than 2%. According to GB / T 18838.3, unbroken steel shot in cast steel grit is a defective particle and should not exceed 5%. With a lower defect percentage, sandblasting can achieve a greater roughness, reaching more than 75um, thus improving the adhesion of the coating.

[0103] Meanwhile, the steel shot content in the sorted steel grit is lower, which can effectively reduce the clogging of the 61 screen holes in the screen component. Spherical steel shot particles are more likely to clog the screen holes. When spherical steel shot that is close to the size of the screen hole cannot pass through the screen hole and is stuck by the screen wire, no matter how much vibration there is, the spherical particles can only rotate in place at the screen hole and cannot pass through the screen hole. However, angular steel shot, due to its size difference, is stuck by the screen wire after being stuck by the screen wire. After vibration and slight rotation, due to the size change, it can pass through the screen hole. At the same time, due to the uniform material distribution of the sorting belt, the screening efficiency is increased by more than 20%, and the steel shot particle size is more uniform and the performance is better.

[0104] Furthermore, the vibrating screen mechanism 6 also includes a vibrator 64 and a vibrating platform 65;

[0105] The vibration platform 65 is located directly below the material discharge baffle 63, the vibrator 64 is installed on the top of the vibration platform 65, and the vibration platform 65 is connected to the bottom of the material discharge baffle 63.

[0106] It should be noted that in this embodiment, the movement of the vibrator 64 causes the discharge baffle 63 to vibrate, and the discharge baffle 63 effectively prevents the steel shot from slipping outside the vibrating screen mechanism 6.

[0107] Furthermore, the crusher assembly 4 includes a frame 41, a discharge hopper 42, and a crushing roller 43;

[0108] The frame 41 is installed on the top of the steel structure platform 1, the crushing roller 43 is relatively rotated inside the frame 41, the discharge hopper 42 is installed at the discharge port at the bottom of the frame 41, and the discharge port of the discharge hopper 42 is above the lower end of the sorting belt 51.

[0109] The elevator 2 includes a horizontal guide chute 22, a horizontal conveying auger 23, a vertical guide cylinder 24, a vertical conveying auger 25, and a discharge port 27;

[0110] The transverse guide trough 22 is connected to the discharge port of the return hopper component 62 and the circulation loop. The transverse conveying auger 23 is rotatably installed at both ends inside the transverse guide trough 22. A vertical guide cylinder 24 is installed in the middle of the transverse guide trough 22. The vertical conveying auger 25 is rotatably installed inside the vertical guide cylinder 24. The top of the vertical guide cylinder 24 penetrates the top of the steel structure platform 1 and is provided with a discharge port 27. The discharge port 27 is located directly above the feeding hopper 3.

[0111] It should be noted that in this embodiment, the steel shot and steel grit can be crushed by the relative rotation between the crushing rollers 43. The relative rotation of the crushing rollers 43 can be driven by gear meshing or other means. The design of the discharge port of the discharge hopper 42 being located above the lower end of the sorting belt 51 allows the steel shot to fall more smoothly into the return hopper component 62, reducing the situation where steel shot falls onto the screen component 61 and forms excessive material accumulation on the screen component 61, thereby ensuring the smooth progress of screening.

[0112] The crusher assembly 4 is modularly arranged and has a simple structure. Two crusher assemblies 4 share one elevator 2 to circulate and crush materials. The vibrating screen mechanism 6 is arranged under the crusher by building a steel structure platform 1, so there is no need for a separate elevator 2 to achieve closed-circuit crushing. The modular arrangement is suitable for multiple sets of crusher assemblies 4 to be arranged horizontally and vertically, which can improve the overall crushing capacity.

[0113] Furthermore, side frames 53 are bolted to both sides of the return frame 8, and an adjustment frame 54 is provided on the inner side of the side frame 53. A sorting roller 52 is rotatably connected to the inner side of the adjustment frame 54, and the sorting belt 51 is sleeved on the outer side of the sorting roller 52.

[0114] The two ends of the sorting roller 52 at the lower end of the sorting belt 51 pass through the adjusting frame 54 and are rotatably connected to the side frame 53. The adjusting frame 54 is equipped with a threaded column 56 on the outer side of the upper end of the sorting belt 51. The side frame 53 is provided with an arc-shaped sliding groove. The threaded column 56 is slidably disposed in the arc-shaped sliding groove. The threaded column 56 extends out of the arc-shaped sliding groove and is threadedly connected to a nut. The nut contacts the outer side of the side frame 53.

[0115] A servo motor 55 is mounted on the outside of the side frame 53, and the output shaft of the servo motor 55 is connected to the end of the sorting roller 52 located at the lower end of the sorting belt 51.

[0116] A servo motor 21 is installed at the end of the transverse guide trough 22, and the output shaft of the servo motor 21 is connected to the transverse conveying auger 23.

[0117] A servo motor 26 is installed on the top of the vertical guide cylinder 24, and the output shaft of the servo motor 26 is connected to the vertical conveying auger 25.

[0118] It should be noted that in this embodiment, by tightening the nut and locking the nut, the adjustment frame 54 can be fixed after the angle is adjusted, thus achieving the effect of adjustable frame 54.

[0119] Driven by the output shaft of the servo motor 55, the sorting roller 52 can rotate, which in turn enables the sorting belt 51 to rotate.

[0120] Driven by the output shaft of servo motor 21, the horizontal conveying auger 23 can rotate, pushing the material in the horizontal guide trough 22. Driven by the output shaft of servo motor 26, the vertical guide cylinder 24 can rotate, conveying the material back into the feeding bin 3.

[0121] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A process for the preparation of high performance steel shot, characterized in that: The preparation process comprises the following steps: S1, after the raw materials are weighed and dosed, melting is carried out by using an electric furnace to obtain a molten steel; S2, the molten steel is refined by argon blowing to reduce the content of dissolved gas in the molten steel; remove the residual non-metallic inclusions in the molten steel; S3, the molten steel in S2 is poured into a tundish and granulated by using a centrifugal granulator to obtain a semi-finished metal abrasive; S4, the semi-finished metal abrasive is dried; S5, the dried abrasive in S4 is quenched, and the hardness is above HRC60; S6, the quenched material in S5 is dried and then crushed; S7, the crushed material in S6 or the quenched material in S5 is tempered to obtain corresponding steel shot, which is carbide-free bainite structure and lath-shaped preformed martensite structure with strip-shaped residual austenite; S8, screening is carried out to obtain high-performance steel shot with the required particle size; The quenching temperature in step S5 is 920-1000℃, the quenching medium in step S5 is a molten liquid salt bath of nitrate solution / mixture; the quenching time in step S5 is 2 hours; Steps S5-S8 comprise a device for preparing steel shot, which comprises a quenching mechanism (100); The quenching mechanism (100) comprises a feeding bin (101), a continuous quenching furnace (102), a furnace barrel (103), a quenching furnace discharge port (104), a ring water ring (105), a quenching water tank (106), and a quenched material outlet (107); One end of the continuous quenching furnace (102) is provided with a feeding bin (101), the continuous quenching furnace (102) has a rotatable furnace barrel (103) inside, and the other end of the continuous quenching furnace (102) is sequentially provided below from top to bottom with a ring water ring (105) and a quenching water tank (106); The discharge port of the feeding bin (101) is in communication with the feeding port of the continuous quenching furnace (102), the quenching furnace discharge port (104) is opened in the uppermost position of the ring water ring (105), the quenching furnace discharge port (104) is in communication with the middle of the ring water ring (105), the ring water ring (105) is in communication with the quenching water tank (106), and the quenching water tank (106) is provided with a quenched material outlet (107) at the side of the bottom end.

2. High performance steel shot steel grit manufacturing process according to claim 1, characterized in that: The quenching medium in step S5 is two-nitrate water; That is, 25% NaNO3+25% NaNO2+50% water by mass percentage, and the use temperature is <60℃.

3. High performance steel shot steel grit manufacturing process according to claim 2, characterized in that: The outer side of the ring water ring (105) is provided with a ring water ring water inlet (109) in communication with the inside of the ring water ring (105); The inner circle of the ring water ring (105) is provided with a ring water ring water nozzle (108) in communication with the ring water ring (105).

4. The high performance steel shot steel grit manufacturing process according to claim 3, characterized in that: The device further comprises a steel sand crushing and screening mechanism (200); The steel sand crushing and screening mechanism (200) comprises a steel structure platform (1), an elevator (2), a feeding bin (3), a crusher assembly (4), a sorting belt (51), a vibrating screen mechanism (6), and a conveyor belt assembly (7). The feeding bin (3) is installed on the top of the steel structure platform (1), the crusher assembly (4) is installed on the top of the steel structure platform (1), the discharge port of the feeding bin (3) is communicated with the feeding port of the crusher assembly (4), the sorting belt (51) is arranged on the bottom of the steel structure platform (1) in an inclined manner, and the vibrating screen mechanism (6) is arranged directly below the discharge port of the sorting belt (51). The vibrating screen mechanism (6) comprises a screen component (61), a return bin component (62) and a material falling baffle (63). The material falling baffle (63) and the screen component (61) are respectively arranged at two ends of the return bin component (62), the return bin component (62) is arranged directly below the sorting belt (51), the low end of the sorting belt (51) is arranged obliquely above the material falling baffle (63), and the high end of the sorting belt (51) is arranged obliquely above the screen component (61). The lifting machine (2) is arranged through the middle of the steel structure platform (1), the discharge port of the lifting machine (2) is communicated with the feeding bin (3), the return bin component (62) is communicated with the lifting machine (2), and the conveying belt assembly (7) is arranged directly below the screen component (61).

5. The high performance steel shot steel grit manufacturing process according to claim 4, characterized in that: The steel structure platform (1) is provided with a return rack (8) at the bottom, the return rack (8) is arranged at two sides of the screen component (61), the return bin component (62) and the material falling baffle (63), a circulation loop is formed between the return rack (8) and the end of the screen component (61), the circulation loop passes through the bottom of the conveying belt assembly (7), and the circulation loop is communicated with the lifting machine (2).

6. High performance steel shot steel grit manufacturing process according to claim 5, characterized in that: The vibrating screen mechanism (6) further comprises a vibrator (64) and a vibrating platform (65). The vibrating platform (65) is arranged directly below the material falling baffle (63), the vibrator (64) is installed on the top of the vibrating platform (65), and the vibrating platform (65) is connected with the bottom of the material falling baffle (63).

7. The high performance steel shot steel grit production process according to claim 6, characterized in that: The crusher assembly (4) comprises a rack (41), a discharge hopper (42) and a crushing roller (43). The rack (41) is installed on the top of the steel structure platform (1), the crushing roller (43) is arranged in the rack (41) in a relative rotating manner, the discharge hopper (42) is installed on the discharge port at the bottom of the rack (41), and the discharge port of the discharge hopper (42) is arranged above the low end of the sorting belt (51). The lifting machine (2) comprises a horizontal material guide groove (22), a horizontal material conveying auger (23), a vertical material guide cylinder (24), a vertical material conveying auger (25) and a discharge port (27). The horizontal material guide groove (22) is communicated with the discharge port of the return bin component (62) and the circulation loop, the horizontal material conveying auger (23) is arranged at two ends in the horizontal material guide groove (22) in a rotating manner, the vertical material guide cylinder (24) is installed in the middle of the horizontal material guide groove (22), the vertical material conveying auger (25) is arranged in the vertical material guide cylinder (24) in a rotating manner, the top end of the vertical material guide cylinder (24) penetrates through the top of the steel structure platform (1) and is provided with the discharge port (27), and the discharge port of the discharge port (27) is arranged above the feeding bin (3).

8. The high performance steel shot steel grit production process according to claim 7, characterized in that: Two sides of the return material frame (8) are provided with side frames (53) through bolt installation, inner sides of the side frames (53) are provided with adjusting frames (54), inner sides of the adjusting frames (54) are rotatably connected with sorting rollers (52), the sorting belt (51) is sleeved on outer sides of the sorting rollers (52); Two ends of the sorting roller (52) at the low end of the sorting belt (51) are rotatably connected on the side frame (53) through the adjusting frame (54), the adjusting frame (54) is provided with a threaded column (56) on the outer side at the high end of the sorting belt (51), the side frame (53) is provided with an arc-shaped sliding groove, the threaded column (56) is slidably arranged in the arc-shaped sliding groove, the threaded column (56) is threadedly connected with a nut outside the arc-shaped sliding groove, and the nut is in contact with the outer side of the side frame (53); The outer side of the side frame (53) is provided with a servo motor three (55), an output shaft of the servo motor three (55) is connected with the end of the sorting roller (52) at the low end of the sorting belt (51); An end of the horizontal material guide groove (22) is provided with a servo motor one (21), an output shaft of the servo motor one (21) is connected with the horizontal material conveying auger (23); A top of the vertical material guide cylinder (24) is provided with a servo motor two (26), an output shaft of the servo motor two (26) is connected with the vertical material conveying auger (25).

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