CN202277862U - Ball milling tank capable of withstanding high pressure and resisting abrasion - Google Patents

Ball milling tank capable of withstanding high pressure and resisting abrasion Download PDF

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CN202277862U
CN202277862U CN2011204145054U CN201120414505U CN202277862U CN 202277862 U CN202277862 U CN 202277862U CN 2011204145054 U CN2011204145054 U CN 2011204145054U CN 201120414505 U CN201120414505 U CN 201120414505U CN 202277862 U CN202277862 U CN 202277862U
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ball grinder
ball milling
ball
milling tank
overcoat
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李姝霖
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Abstract

The utility model discloses a ball milling tank capable of withstanding high pressure and resisting abrasion. The ball milling tank comprises an outer sleeve, an inner lining, a valve, a seal ring and a grinding ball arranged in a ball tank, wherein the outer sleeve is made of a metal material with higher yield strength, the inner lining is made of the metal material with high abrasion resistance, and the outer sleeve is tightly combined with the inner lining; and the seal ring is mounted in a groove on the surface of the outer sleeve. The ball milling tank is characterized in that the outer sleeve of the ball milling tank is made of the metal material with the higher yield strength so as to be capable of withstanding high-pressure gas, and the inner lining of the ball milling tank is made of the metal material with the high abrasion resistance so as to be capable of improving the abrasion resistance of the ball milling tank and improve a contact fatigue performance. The outer sleeve and the inner lining of the ball milling tank are combined, so that toughness and hardness are complementary, the impact resistance of the ball milling tank is improved, the service life of the ball milling tank is prolonged and the ball milling tank is safer and more reliable.

Description

A kind ofly can bear high pressure and wear-resisting ball grinder
Technical field
The utility model relates to the plant equipment field; Be a kind of ball grinder that can bear gases at high pressure and high-wearing feature specifically; Be mainly used in mechanical alloying and the high-energy ball milling equipment, be widely used in fields such as geology, mineral products, metallurgy, soil, electronics, chemical industry, medicine, environmental protection, building materials, battery, biochemistry, the ball grinder impact resistance of the utility model is good; Long service life can be according to different model ball mill design different size.
Background technology
At present, each manufacturing enterprise and research institutions are for various powder preparing, the ball grinder of several kinds of materials below mechanical alloying and high-energy ball milling aspect are mainly used: stainless steel, pottery, polyurethane, nylon, zirconia etc.The ball grinder of above material respectively has pluses and minuses in use, and corrosion-resistant though stainless steel jar mill is high pressure resistant, hardness is low, introduces impurity easily.Though pottery, zirconia ball milling jar hardness height, anti-wear performance is good, is difficult to process the large scale ball grinder, and impact resistance is not high, after charging into gases at high pressure, in the high-speed impact mechanical milling process, is easy to fragmentation.Though nylon, polyurethane ball grinder wearability are fine, ball material impact energy is not high when the high speed ball milling, and is difficult to charge into the gases at high pressure protection.
The utility model content
Can not have wear-resisting and withstand voltage shortcoming concurrently in order to overcome existing ball grinder, the utility model provides a kind of compound ball grinder, and concrete scheme is following:
A kind ofly can bear high pressure and wear-resisting ball grinder; Comprise overcoat, liner, valve, sealing ring and be arranged on the abrading-ball in the spherical tank; It is characterized in that: said lagging material adopts the higher metal material of yield strength; Said inner lining material adopts the high metal material of anti-wear performance, and said overcoat and said liner are combined closely; Said sealing ring is installed in the groove on the said circumferential surface;
Said liner wall thickness is chosen between the 1-30 millimeter, and the ratio of liner and overcoat wall thickness is 1: 0.2-1: 10;
The ratio of said liner wall thickness and said overcoat wall thickness is 1: 2-1: 4;
Said inner lining material adopts bearing steel GCr15, and said lagging material adopts 304 stainless steels; Said grinding ball material adopts GCr15;
Said inner lining material adopts high carbon and chromium martensitic stainless steel 9Cr18, and said grinding ball material adopts high carbon and chromium martensitic stainless steel 9Cr18;
Lost efficacy for fear of the concentrated ball grinder overcoat flange that makes of the stress that causes owing to the ball grinder internal pressure; Improve the compressive resistance of ball grinder overcoat; Said overcoat flange connections is inclined-plane or arc, has improved the intensity of flange, if adopt right-angle design; Because the ball grinder internal gas pressure can produce stress and concentrate on the top, right angle, adopt the design of inclined-plane or arc; Inclined-plane or arc design are adopted in ball grinder liner and overcoat junction; For guaranteeing that abrading-ball fully contacts with the ball grinder liner, the ball grinder liner adopts the arc design;
The invention also discloses a kind of manufacturing approach of above-mentioned ball grinder, it is characterized in that: said liner process comprises: forging, isothermal spheroidizing, machined, vacuum hardening add lonneal, corase grind adds grinding; Said isothermal spheroidizing technology is: be heated to 780 ℃ of insulations 4 hours, cool to 720 ℃ of insulations 6 hours with the furnace; Said vacuum hardening adds lonneal technology: be heated to 660 ℃ of insulations 30 minutes, rise to 850 ℃ of insulations 30 minutes again, oil cooling is heated to 160 ℃ of insulations at last and is cooled to normal temperature after 120 minutes to normal temperature; At 850 ℃ of oil coolings was vacuum state in the past, and charging into high pure nitrogen to pressure when oil cooling begins is 8 * 10 4Pa;
Said lagging material is selected stainless steel; Adopt heat edge technology, be heated to 120 ℃-180 ℃ to said overcoat integral body earlier, be incubated after 1-5 hour; Slowly be embedded in said liner in the said overcoat again, treat that said overcoat is cooled to room temperature after, mounted valve and sealing ring; Carry out the water pressure test earlier, after the water pressure test is errorless, charge into gas a little less than hydraulic pressure from the valve air inlet; Inspection ball grinder sealing can be used after all are errorless.
The utility model has the advantages that: adopting different metal materials is the compounded ball grinders of raw material, and the ball grinder overcoat selects the higher high pressure resistant metal material of yield strength to process, and plays and bears gases at high pressure or vacuum action.The ball grinder liner selects the high abrasion-resistant stee of anti-wear performance can improve the anti-wear performance of ball grinder.Through being installed in the valve on the ball grinder, can vacuumize or charge into certain pressure gas to ball grinder.Sealing ring is chosen in installation on the coat; The gas pressure that has guaranteed to charge into ball grinder acts directly on and puts rather than act on the liner outward; At working pressure is can use nonmetal sealing ring below the 2.0MPa, is higher than 2.0MPa and can selects to use metal o-ring.In the high speed mechanical milling process; The high speed rotation and the bump of spheroid also have very big damage to ball grinder; The ball grinder of the utility model has not only been realized high pressure resistant and wear-resisting characteristics, and being distributed to outside the ball grinder of energy even that the spheroid bump is produced at the abrasion-resistant stee of ball grinder liner puts, and played fabulous damping effect; Improve its impact resistance greatly, increased service life.
The another one characteristics of the utility model are that introducing impurity is few in the mechanical milling process; Bought and the identical steel ball of ball grinder internal layer material hardness because on market, hold very much; Therefore the impurity that both produce in mechanical milling process is few, has improved greatly by the purity of ball milling material.
The disclosed processing technology of the utility model if produce in batch, can reduce production costs greatly.
Description of drawings
Fig. 1 is the longitudinal sectional drawing of the utility model;
Fig. 2 is GCr15 isothermal spheroidizing process curve figure;
Fig. 3 is GCr15 vacuum hardening process curve figure;
1. valves among the figure, 2. overcoat on the ball grinder, 5. ball grinder side overcoat, 3. neck bush on the ball grinder, 6. the ball grinder sidelining 4. is a sealing ring.
The specific embodiment
Below in conjunction with accompanying drawing and embodiment the utility model is further specified.
As shown in Figure 1; The structure of the utility model comprises overcoat, liner, valve 1, sealing ring 4 and is arranged on the abrading-ball in the spherical tank; Said overcoat comprises overcoat 2 and ball grinder side overcoat 5 on the ball grinder, and said lagging material adopts the higher metal material of yield strength, and said liner comprises neck bush 3 on ball grinder sidelining 6 and the ball grinder; Said inner lining material adopts the high metal material of anti-wear performance, and said overcoat and said liner are combined closely; Said sealing ring 4 is installed in the groove on the said circumferential surface, and said valve 1 is installed on the ball grinder.
The ball grinder inner lining material adopts bearing steel GCr15, and the ball grinder lagging material adopts 304 stainless steels; The grinding ball material that is provided with in the ball grinder adopts the GCr15 bearing steel ball.
The ball grinder inner lining material also can adopt high carbon and chromium martensitic stainless steel 9Cr18, and the grinding ball material that be provided with in the ball grinder this moment adopts the 9Cr18 steel ball.
Lost efficacy for fear of the concentrated ball grinder overcoat flange that makes of the stress that causes owing to the ball grinder internal pressure; Improve the compressive resistance of ball grinder overcoat; Ball grinder overcoat flange connections 51 and the 21 employing inclined-planes, junction or the arc design of going up overcoat have improved the intensity of flange, if adopt right-angle design; Because the ball grinder internal gas pressure can produce stress and concentrate on the top, right angle, adopt the design of inclined-plane or arc; Inclined-plane or arc design are adopted in ball grinder liner and overcoat junction; For guaranteeing that abrading-ball fully contacts with the ball grinder liner, the ball grinder liner adopts the arc design;
The manufacturing approach of the utility model ball grinder:
Ball grinder according to required ball mill model design corresponding size profile.
The ball grinder liner can be selected bearing steel or mould steel, is example with bearing steel GCr15 below, because GCr15 has higher hardness, uniform tissue, good wearability, high contact fatigue property after adding tempering through quenching.In the mechanical milling process; Ball is a little with liner or line contacts; Bear very big compression (up to 1800MPa-5000MPa) and alternate load; The GCr15 steel has high anti-fatigue performance, long service life and cheap, and be easy to buy hardness is suitable with it GCr15 steel ball as the ball grinder abrading-ball.
With GCr15 is that ball grinder inner lining material (with external diameter 150mm, wall thickness 6mm is an example) process embodiment is following:
Embodiment 1: the manufacturing approach of said ball grinder, and process comprises: forging, isothermal spheroidizing, machined, quenching add lonneal, corase grind adds grinding; Said isothermal spheroidizing technology is: be heated to 780 ℃ of insulations 4 hours, cool to 720 ℃ of insulations 6 hours with the furnace; Said vacuum hardening adds lonneal technology: be heated to 660 ℃ of insulations 30 minutes, rise to 850 ℃ of insulations 30 minutes again, oil cooling is heated to 160 ℃ of insulations at last and is cooled to normal temperature after 120 minutes to normal temperature.At 850 ℃ of oil coolings was vacuum state in the past, and charging into high pure nitrogen to pressure when oil cooling begins is 8 * 10 4Pa.
Embodiment 2: the manufacturing approach of said ball grinder, and process comprises: forging, isothermal spheroidizing, machined, quenching add lonneal, corase grind adds grinding; Said isothermal spheroidizing technology is: be heated to 780 ℃ of insulations 4 hours, cool to 720 ℃ of insulations 6 hours with the furnace; Said vacuum hardening adds lonneal technology: be heated to 660 ℃ of insulations 30 minutes, rise to 850 ℃ of insulations 10 minutes again, oil cooling is heated to 160 ℃ of insulations at last and is cooled to normal temperature after 120 minutes to normal temperature.At 850 ℃ of oil coolings was vacuum state in the past, and charging into high pure nitrogen to pressure when oil cooling begins is 8 * 10 4Pa.
Embodiment 3: the manufacturing approach of said ball grinder, and process comprises: forging, isothermal spheroidizing, machined, quenching add lonneal, corase grind adds grinding; Said isothermal spheroidizing technology is: be heated to 800 ℃ of insulations 3 hours, cool to 720 ℃ of insulations 4 hours with the furnace; Said vacuum hardening adds lonneal technology: be heated to 660 ℃ of insulations 30 minutes, rise to 860 ℃ of insulations 30 minutes again, oil cooling is heated to 160 ℃ of insulations at last and is cooled to normal temperature after 120 minutes to normal temperature.At 860 ℃ of oil coolings was vacuum state in the past, and charging into high pure nitrogen to pressure when oil cooling begins is 8 * 10 4Pa.
Embodiment 4: the manufacturing approach of said ball grinder, and process comprises: forging, isothermal spheroidizing, machined, quenching add lonneal, corase grind adds grinding; Said isothermal spheroidizing technology is: be heated to 810 ℃ of insulations 4 hours, cool to 720 ℃ of insulations 4 hours with the furnace; Said vacuum hardening adds lonneal technology: be heated to 660 ℃ of insulations 30 minutes, rise to 860 ℃ of insulations 10 minutes again, oil cooling is heated to 160 ℃ of insulations at last and is cooled to normal temperature after 120 minutes to normal temperature.At 860 ℃ of oil coolings was vacuum state in the past, and charging into high pure nitrogen to pressure when oil cooling begins is 8 * 10 4Pa.
The purpose of isothermal spheroidizing is to reduce GCr15 hardness, is convenient to machining, also prepares for final heat treatment, quenches and does the tissue preparation, observes the globular pearlite that is organized as uniform and delicate after the isothermal spheroidizing down from metallographic microscope.Metallographic structure after the utility model quenches is a cryptocrystalline martensite, the undissolved carbide that distributing above that, and it can guarantee the requirement of comprehensive mechanical property.Its optical microstructure is made up of black, white alternate Liang Zhongmashi body region, in the black M-region, has more carbide particle, and is then fewer in the white portion.Guarantee after the final heat treatment that hardness is between HRC62-66.Experimental result is seen table 1.
Table 1
Figure BDA0000102517860000041
Can find out that by table 1 embodiment 1 hardness is moderate, approaching with GCr15 bearing steel ball hardness, and the variation in diameter amount is very little, for follow-up attrition process and assembling provide ideal conditions.
The variation in diameter amount also meets grinding and matching requirements among the embodiment 2; But because 850 ℃ of temperature retention times are too short when vacuum hardening; Workpiece does not wait heat to pass to the i.e. cooling rapidly in center, is hardened in the top layer and is that martensite, center still are unhardened original plasticity, toughness annealed structure preferably; Though highest hardness has reached HRC 62, Hardness Distribution is even not as embodiment 1.
Though hardness is up to HRC 66 among the embodiment 3, the variation in diameter amount crosses greatly 0.35, for follow-up attrition process and assembling make troubles.
The variation in diameter amount slightly greatly 0.25 among the embodiment 4, though can in follow-up attrition process, correct, hardness is similar among its hardness and the embodiment 2, and Hardness Distribution is even not as embodiment 1.
The purpose of isothermal spheroidizing is to reduce GCr15 hardness, is convenient to machining, also prepares for final heat treatment, quenches and does the tissue preparation, observes the globular pearlite that is organized as uniform and delicate after the isothermal spheroidizing down from metallographic microscope.Metallographic structure after the utility model vacuum hardening is a cryptocrystalline martensite, the undissolved carbide that distributing above that, and it can guarantee the requirement of comprehensive mechanical property.Its optical microstructure is made up of black, white alternate Liang Zhongmashi body region, in the black M-region, has more carbide particle, and is then fewer in the white portion.Guarantee after the final heat treatment that hardness is between HRC63-65.
Theoretically; The hardening heat of GCr15 steel is about 840 ℃; Fatigue strength and hardness are all the highest behind the Q-tempering, and impact toughness is also best, when about 840 ℃, quenching in the austenite mass fraction of dissolved carbon be 0.5%-0.6%; The mass fraction of chromium is 0.8%, also has the undissolved carbide of part.Carbon that dissolves in and alloying element have then guaranteed its quenching degree and hardenability, and the carbide that dissolves has stoped grain growth, if hardening heat is on the low side, then to dissolve in austenitic amount few for carbide, and carbon in the austenite and chromium content are low, have influence on the hardness after the quenching.Hardening heat is too high, and it is overheated then can to cause, makes the back martensitic needles of quenching thick, is out of shape also greatly, affects the mechanical properties.Heat time heating time and heating-up temperature, heat transfer medium, workpiece effective thickness and batch all have close ties.Vacuum hardening process curve as shown in Figure 3 disclosed in the utility model, quenching temperature is 850 ℃, suitably controls cool time simultaneously, all through hardening, hardness reaches HRC63-65, and institute's target vacuum is vacuum meter show value in the actual production among the figure.Suitably improve preheat temperature, can improve firing rate, shorten heat time heating time and do not cause crystal grain thick, reduce production costs.
The ball grinder lagging material can be selected stainless steel; With 304 stainless steels is example, processes corresponding stainless steel outer sleeve size according to the ball mill of different model, reserves the position of mounted valve and air inlet; Reserving equally distributed through hole on every side uses as bolted; Sealing ring is installed in the groove on the steel flange face, has guaranteed when charging into gases at high pressure or vacuum, is that stainless steel outer sleeve is being born high pressure or vacuum.
The ball grinder overcoat is consistent with liner dimensional requirement on inside and outside circle and length, does not allow bigger deviation.After all parts are according to the design drawing completion of processing, utilize principle of expanding with heat and contracting with cold, adopt heat edge technology, be heated to 120 ℃-180 ℃ to stainless steel outer sleeve integral body earlier; Be incubated after 1-5 hour, slowly be embedded in the bearing steel liner in the stainless steel outer sleeve again, treat that stainless steel is cooled to room temperature after; Mounted valve and sealing ring carry out the water pressure test earlier, after the water pressure test is errorless; Charge into the gas a little less than hydraulic pressure from the valve air inlet, inspection ball grinder sealing can be used after all are errorless.
Ball grinder liner wall thickness is chosen between the 1-30 millimeter, and the ratio of liner and overcoat wall thickness is 1: 0.2-1: between 10, best ratio is 1: 2-1: 4, and the overcoat wall thickness is big more, and the gas pressure that bears is big more.With ball grinder overcoat wall thickness 8mm, ball grinder flange thickness 10mm, ball milling cover thickness 12mm is an example, and material is 304 stainless steels, and hydraulic test pressure is 3.5MPa.According to the gas pressure size that ball milling condition uses, design the ball grinder overcoat of corresponding size about the steel pipe flanges design standard with reference to country.
If be corrosive medium in the mechanical milling process, can select high carbon and chromium martensitic stainless steel 9Cr18 as the ball grinder liner, select alloy tool steel Gr12MoV also can reach with GCr15 effect same.
Selecting then on the material, be applicable to that the metal material of the utility model ball grinder overcoat and liner is a lot, as: select can select G8Cr15, GCrSiWV, 9Cr18Mo etc. on the material at the ball grinder liner.The G8Cr15 characteristics are to have improved the carbide inhomogeneities of steel, are prone to obtain evenly tiny spheroidizing tissue, have improved hot and cold deformation performance and cutting ability, and fatigue life ratio GCr15 steel is high.GCrSiWV has hardness height, wearability and dimensional stability and reaches the long characteristics of contact fatigue life well.9Cr18Mo performance and 9Cr18 are suitable, have been applicable under the corrosive medium environment and ball grinder liner during strong oxidation environment ball milling.
On the ball grinder lagging material is selected, can select 12Ni3CrMoV or 10Ni5CrMoV, their tensile strength having the high-intensity while, has high tenacity at 600-800MPa.304L stainless steel, 316 stainless steels can be as the ball grinder lagging materials, and be not only withstand voltage, rust resistance and corrosion resistance, and ball milling can play the hydrogen embrittlement effect that prevents under the hydrogen environmental condition if having.

Claims (4)

1. one kind can be born high pressure and wear-resisting ball grinder; Comprise overcoat, liner, valve, sealing ring and be arranged on the abrading-ball in the spherical tank; It is characterized in that: said lagging material adopts the higher metal material of yield strength; Said inner lining material adopts the high metal material of anti-wear performance, and said overcoat and said liner are combined closely; Said sealing ring is installed in the groove on the said circumferential surface.
2. ball grinder according to claim 1 is characterized in that: said overcoat flange connections is inclined-plane or arc.
3. ball grinder according to claim 1 is characterized in that: said liner wall thickness is chosen between the 1-30 millimeter, and the ratio of liner and overcoat wall thickness is 1: 0.2-1: 10.
4. ball grinder according to claim 1 is characterized in that: the ratio of said liner wall thickness and said overcoat wall thickness is 1: 2-1: 4.
CN2011204145054U 2011-10-26 2011-10-26 Ball milling tank capable of withstanding high pressure and resisting abrasion Expired - Fee Related CN202277862U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102430455A (en) * 2011-10-26 2012-05-02 李姝霖 Ball-milling tank capable of bearing high pressure and resisting abrasion, and manufacturing method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102430455A (en) * 2011-10-26 2012-05-02 李姝霖 Ball-milling tank capable of bearing high pressure and resisting abrasion, and manufacturing method thereof

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