CN1125777A - Centrifugal compound wear-resistant grinding roller and production method thereof - Google Patents

Centrifugal compound wear-resistant grinding roller and production method thereof Download PDF

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CN1125777A
CN1125777A CN 95113322 CN95113322A CN1125777A CN 1125777 A CN1125777 A CN 1125777A CN 95113322 CN95113322 CN 95113322 CN 95113322 A CN95113322 A CN 95113322A CN 1125777 A CN1125777 A CN 1125777A
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cast iron
grinding roller
wear
pouring
high wear
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CN 95113322
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CN1044574C (en
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管庆法
胡建政
黄德忠
何德富
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LIN'AN WEAR-RESISTANT PARTS GENERAL FACTORY HANGZHOU
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LIN'AN WEAR-RESISTANT PARTS GENERAL FACTORY HANGZHOU
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Abstract

The composite grinding roller in the shape of wheel with central hole for installation is composed of ordinary cast iron layer as core, fusion joint layer and antiwear cast alloy iron layer as external one, which contains C (2.2-3.2 Wt.%), Si (0.8-1.5), Mn (0.7-1.5), Cr (0.9-2.5), Ni (0.5-1.2), Cu (0.3-0.6), S (less than 0.06), P (less than 0.06) and Fe (rest), and is made up by casting in centrifugal and dual-smelting mode. It is suitable for grinding non-metal material.

Description

Centrifugal compound wear-resistant roll and production method thereof
The present invention relates to the size reduction machinery of industries such as a kind of and mining, cement, wilkinite composite grinding roll supporting, that wear-resisting shell and tough and tensile core are formed, and connect with centrifugal and two molten refinings and to cast the methods of composite grinding rolls.
How grinding roller in the size reduction machinery of industries such as cement is raw material with tough white pig iron, high mangaenese steel, adopts the ordinary method casting to form, and this method is because of the setting of pouring and riser systems, and molten iron utilizes rate variance, and energy dissipation is serious.The grinding roller that this conventional teeming practice is produced easily produces casting flaws such as pore, shrinkage porosite, cold shut, trachoma, is difficult to guarantee the quality of product.The grinding roller that this single material is cast, outer working face and sandwich layer department of assembly form by the high material of valency of fine quality, have both caused the preparation of material unreasonable, and product cost is strengthened.
States such as Japan in steel composite roll, have a lot of research to the rotary casting production application, and from disclosed several patent achievements, selecting for use of its technology and material is each has something to recommend him, differs from one another.But, do not find similar report as yet for centrifugal and melting series system casting composite grinding roll.
Therefore, the present invention to be to adopt centrifugal and two molten refining series systems, and it is purpose that composite grinding roll that the good alloy outer of wear resistance, tough and tensile cast iron core and the good middle layer of welding form and the method for producing this grinding roller are provided.
Purpose of the present invention can realize with following measure: its integral body is wheel shape, central part has axial open holes, skin is made by high wear-resistant ally cast iron, sandwich layer is by tough and tensile iron casting, the welding layer is arranged between skin and the sandwich layer, the composition of said outer high wear-resistant ally cast iron constitutes, its weight ratio is 2.2-3.2% C, 0.8-1.5% Si, 0.7-1.5% Mn, 0.9-2.5% Cr, 0.5-1.2% Ni, 0.3-0.6% Cu, S less than 0.06%, P less than 0.06%, all the other are Fe and unavoidable impurities.
The Re that also can contain trace in the outer high wear-resistant ally cast iron of this grinding roller.
The method of producing this composite grinding roll realizes with centrifugal and two melting series systems.To fused cast iron add with its weight ratio be that 0.8-1.3% No. 75 quarrel powder carry out inoculation, to fused high wear-resistant ally cast iron add with its weight ratio be the processing of going bad of 0.4-0.6% No. 1 rare earth alloy, high wear-resistant ally cast iron teeming temperature is 1360-1400 ℃, the teeming temperature of tough and tensile cast iron is 1360-1380 ℃, be 1-5 minutes the pitch time of pouring into a mould cast iron after the cast of high wear-resistant ally cast iron again, the rotating speed of centrifugal casting machine in casting process, its linear velocity are 13-25 meter per seconds.
Produce in the method for this composite grinding roll, the best teeming temperature of high wear-resistant ally cast iron is 1380-1400 ℃, the best teeming temperature of cast iron is 1370-1380 ℃, it is 2-3 minutes that the best between them is poured into a mould pitch time, the rotating speed of centrifugal casting machine in casting process, closing the linear velocity of making most is 13-22 meter per seconds.
Fig. 1 is this composite grinding roll structural representation.
Fig. 2 is this composite grinding roll technological process of production figure.
Component and the weight ratio thereof of one, making the outer field high wear-resistant ally cast iron of this composite grinding roll are:
Carbon (C): 2.2-3.2%, C is the important unit that outer wear resistence requires Element, C content is too high, and outer field crack resistance is poor, crosses low then outer field wearing no resistance, The approrpiate wts ratio that the present invention contains C is 2.2-3.2%, and optimum weight ratio is 2.2-3.0%.
Silicon (Si): 0.8-1.5%, reasonably si content helps to carry in the present invention High-wearing feature, Si content surpasses 2%, not only reduces wearability, casting also can occur Defective, suitable content are 0.8-1.5%.
Manganese (Mn): 0.7-1.5%, Mn can improve quenching degree, but very easily produces Segregation, Mn also has deoxidation, eliminates the adverse effect of sulphur (S). Its suitable containing Amount is 0.7-1.5%, and optimum content is 0.8-1.2%.
Chromium (Cr): 0.9-2.5%, Cr is conducive to improve intensity and hardness, and content is many Free carbide can occur, easily produce hot tearing, appropriate level 0.9-2.5%, the best Content 1.0-2.0%.
Nickel (Ni): 0.5-1.2%, it is obvious that Ni helps improving the effect of mechanical property, can improve big area THE STRUCTURE OF CASTINGS, intensity and hardness, improves toughness and plasticity, do not produce the undesirable action that causes because of segregation.Optimum content is 0.7-1.1%.
Copper (Cu): 0.3-0.6%, copper has the effect that improves tensile strength and yield-point, improves wear resistance and improves fatigue strength, obviously improves the fractography homogeneity.Suitable contain the reason be 0.3-0.6%.
Sulphur (S):＜0.06%, S can consume rare earth alloy and form slag inclusion, subsurface porosity, makes mechanical properties decrease, so contain the S amount with less for well.
Phosphorus (P):＜0.06%, the small increase of P content will obviously reduce mechanical property, influences impact toughness, so should be controlled at below 0.06%.
Radium (Re): Re mixes when go bad processing as the rare earth alloy that adds No. 1,0.4-0.6% weight ratio.So the Re element of trace should be arranged.
Two, two melting series connection castings:
Can still at interval use according to continuous use, every order order of classes or grades at school what etc. factor, two meltings series connection stoves are rationally matched.The present invention is that the intermediate frequency furnace that 1.5 tons/hour cupola furnace and capacity are 0.5 ton matches with a capacity, dashes no stove melting iron, when going out molten iron, carries out inoculation by No. 75 commercially available silica flours of 0.8-1.3% weight ratio adding of molten iron total amount.Fusing high wear-resistant ally cast iron in intermediate frequency furnace, this cast alloy iron can be with following raw material and weight ratio input thereof: 60-68% cast iron molten hot metal, 7-10% stainless steel (1Cr18Ni9Ti), 1-1.5% manganeseirom, 25-35% steel scrap, 0.3-0.8% ferrochrome, 0.8-1.2% nickel block and 5-7% steel scrap substitute, after the above-mentioned raw materials fusion is come out of the stove, add the processing of going bad of 0.4-0.6% No. 1 rare earth alloy that this cast alloy iron is cast into the outer weight of grinding roller, start the centrifugal casting machine of speed change, elder generation's impouring fused high wear-resistant ally cast iron in casting mold, after weighing, at interval behind the certain hour again the impouring fused end until spill-over through the cast iron of inoculation.Remove pouring mouth again, discharging water through about 3 minutes is cooled to about 600 ℃, or foundry goods is when becoming garnet, and inloading part buried the sand slow cooling about 12 hours, the pickup polishing, check.
Three, several of rotary casting key issues:
In rotary casting, the key of this composite grinding roll manufacturing success is rationally to match under the prerequisite of material, must get hold of the rotating speed of pouring temperature, pitch time and centrifugal casting machine.Total principle is that the teeming temperature of cast alloy iron should be higher than plain cast iron; Should take all factors into consideration teeming temperature pitch time, and factors such as iron layer thickness and casting mold radiating condition are come fixed; The rotating speed of centrifugal casting machine should be considered vertical and horizontal the different of gravity factor that overcome, the requirement of the reasonable density of foundry goods, requirement such as principal element diffusion in the welding layer between skin and the sandwich layer, fusion are suitable.In identical rotating speed (circular frequency), molten hot metal at outer field centrifugal force greater than sandwich layer, in order to reach the centrifugal force of basically identical, make density even, the circular frequency when watering skin should be less than the circular frequency that waters sandwich layer, it is the rotating speed (circular frequency) of centrifugal casting machine, by watering sandwich layer outward should be progressively to accelerate, and promptly 600-800-1200 rev/mins increase progressively, at the present invention, unified with the linear velocity definite value, more problem can be described.
The teeming temperature that the present invention makes composite grinding roll requirement high wear-resistant ally cast iron is 1360-1400 ℃, and the best is 1380-1400, and the teeming temperature of plain cast iron is 1360-1380 ℃, best 1370-1380 ℃.Be 1-5 minutes pitch time, best 2-3 minutes.The linear velocity of centrifugal casting machine in casting process is controlled at 13-25 meter per seconds, best 13-22 meter per seconds.
It should be noted that each material composition in this casting all is commercially available, relevant frock such as casting mold need add gentle brushing paintcast before cast.Breed and rotten processing also belongs to ordinary method.
Embodiment 1:
With an internal diameter is that 410mm, the degree of depth are 205mm, water the hollow garden tube mould that bore dia is 100mm, with 125Kg have shown in the table 1 in the fusion high wear-resistant ally cast iron of arbitrary sequence number prescription and 47Kg fused plain cast iron respectively under teeming temperature is 1400 ℃ and 1380 ℃ of conditions, 4 minutes at interval, centrifugal casting machine rotating speed control line speed is 20 meter per seconds, and carrying out rotary casting, to become the external form diameter be that 406mm, open holes aperture are 100mm, highly are the wear-resistant composite grinding roll of 195mm.
Table 1 (chemical component weight %) sequence number C% Cr% Si% Mn% Cu% Ni% S% P% Re%1 3.2 1.66 1.35 1.21 0.52 0.68 0.08 0.072 2.3 1.42 1.07 0.86 0.41 0.71 0.09 0.0653 2.95 2.09 1.46 1.11 0.40 1.0 0.085 0.0764 2.67 1.2 1.14 0.72 0.50 0.6 0.08 0.075 2.64 1.4 0.93 0.82 0.42 0.7 0.09 0.0736 2.81 1.63 0.98 1.44 0.43 0.81 0.08 0.07
According to the weight % of each chemical ingredients in the last table, what be converted into each furnace charge selects and drops into proportional quantity for use, is that industry those of ordinary skill can be grasped, and in the aforementioned pair of melting series connection castmethod concrete narration is arranged once also, does not carefully state for this reason.
Several key requests of rotary casting make up as table 2:
123456 centrifugal casting machine rotating speed 13 17 20 22 25 20 linear velocities (meter per second) second pouring pitch times 1.5 2 2.2 2.5 45 of table 2 sequence number (minute) cast alloy iron teeming temperature 1,365 1,370 1,380 1,390 1,380 1400
(℃) plain cast iron teeming temperature 1,360 1,360 1,370 1,380 1,370 1380
(℃)
Embodiment 2:
With an internal diameter is that 308mm, the degree of depth are 175mm, water the hollow garden tube mould that bore dia is 70mm, fusion high abrasion-resistant alloy cast iron with 65Kg with the arbitrary sequence number prescription shown in the table 1,31Kg fused plain cast iron, the condition combination of arbitrary sequence number that its teeming temperature, centrifugal casting machine rotating speed, pitch time are as shown in table 2 is carried out rotary casting and is become diameter 302mm, open holes aperture to be 70mm, highly to be the high wear-resistant composite grinding roll of 165mm down.
Embodiment 3:
With an internal diameter is that 212mm, the degree of depth are 150mm, water the hollow garden tube mould that bore dia is 40mm, fusion high wear-resistant ally cast iron with the prescription of 22Kg with the arbitrary sequence number shown in the table 1, the fusion plain cast iron of 10Kg, the rotating speed of its teeming temperature, centrifugal casting machine, arbitrary sequence number condition combination as shown in table 2 pitch time are descended, carry out rotary casting, the one-tenth external diameter is that 207mm, open holes aperture are 40mm, highly are the wear-resistant composite grinding roll of 140mm.
Press the prescription of table 1, the condition combination of pressing table 2 in a word, also can be as required, external diameter, open holes aperture, highly both can make the grinding roller bigger than embodiment 1, and also can make the grinding roller littler than embodiment 3, this needs to adjust relevant size of mould and the iron water amount that dissolves of increase and decrease cast gets final product.
Casting flaws such as the no macroscopic crackle in centrifugal compound wear-resistant roll that the present invention makes surface, tangible cold shut, pore, splashings, the hardness (HRC) of this grinding roller skin (alloy layer) 1 are greater than 40, impact value 〉=6.0 joule/cm 2Sandwich layer 3 is strong but pliable in texture, and the diffusion of welding layer 2 principal element is suitable, and thickness meets structural requirement, and open holes 4 meets the dimensional requirement of installation.
The present invention uses centrifugal and two melting series connection method casting compound wear-resistant rolls, the molten iron utilization ratio height of the grinding roller of producing than the disposable normal pouring of single material, save the energy, be difficult for producing casting flaws such as pore, shrinkage porosite, cold shut, trachoma, the class that improves the quality of products, outer high wear-resistant ally cast iron and the tough and tensile plain cast iron of sandwich layer are given full play to mechanical property separately, have a role to play, also saved production cost greatly.

Claims (6)

1.一种离心复合耐磨磨辊，整体呈轮形，中心部有轴向的安装孔(4)，其特征在于外层(1)由高抗磨合金铸铁制造，芯层(3)由坚韧的普通铸铁制造，外层与芯层之间有熔接层(2)，所说的外层(1)的高抗磨合金铸铁的成分构成，其重量比为2.2—3.2％的C，0.8—1.5％的Si，0.7—1.5％的Mn，0.9—2.5％的Cr，0.5—1.2％的Ni，0.3—0.6％的Cu，小于0.06％的S，小于0.06％的P，其余为Fe和不可避免的杂质。1. A centrifugal composite wear-resistant grinding roller, which is in the shape of a wheel as a whole, and has an axial mounting hole (4) in the center, and is characterized in that the outer layer (1) is made of high wear-resistant alloy cast iron, and the core layer (3) is made of Made of tough ordinary cast iron, there is a welded layer (2) between the outer layer and the core layer. The composition of the outer layer (1) is high wear-resistant alloy cast iron, and its weight ratio is 2.2-3.2% C, 0.8 -1.5% Si, 0.7-1.5% Mn, 0.9-2.5% Cr, 0.5-1.2% Ni, 0.3-0.6% Cu, less than 0.06% S, less than 0.06% P, and the rest are Fe and unavoidable impurities. 2.如权利要求1所述的磨辊，其特征是所说的外层高抗磨合金铸铁含有微量的Re。2. The grinding roller according to claim 1, characterized in that said outer layer of high wear-resistant alloy cast iron contains a trace amount of Re. 3.如权利要求1所述的复合磨辊的生产方法，其特征是采用离心和双熔炼串联方法生产的，对熔融的普通铸铁加入与其重量比为0.8—1.3％的75号硅粉进行孕育处理，对熔融的高抗磨合金铸铁加入与其铸造磨辊外层合金重比为0.4—0.6％的1号稀土合金进行变质处理，在高抗磨合金铸铁浇注温度为1360—1400℃，普通铸铁浇注温度为1360—1380℃，两次浇注的间隔时间为1—5分钟，离心铸机在浇注过程中的转速，其线速度为13—25米/秒。3. The production method of the composite grinding roller as claimed in claim 1, characterized in that it is produced by means of centrifugation and double smelting in series, adding No. 75 silicon powder with a weight ratio of 0.8-1.3% to the molten common cast iron to inoculate Treatment, adding No. 1 rare earth alloy with a weight ratio of 0.4-0.6% to the molten high-wear-resistant alloy cast iron and the outer layer alloy of the casting grinding roller for modification treatment. The pouring temperature is 1360-1380°C, the interval between two pours is 1-5 minutes, and the rotational speed of the centrifugal casting machine during the pouring process is 13-25 m/s. 4.如权利要求3所述的方法，其特征是普通铸铁的最佳浇注温度为1370—1380℃，高抗磨合金铸铁的最佳浇注温度为1380—1400℃。4. The method according to claim 3, characterized in that the optimum pouring temperature of ordinary cast iron is 1370-1380°C, and the optimum pouring temperature of high wear-resistant alloy cast iron is 1380-1400°C. 5.如权利要求3所述的方法，其特征是高抗磨合金铸铁浇注后再浇注普通铸铁的最佳间隔时间为2—3分钟。5. The method according to claim 3, characterized in that the best interval between pouring of high wear-resistant alloy cast iron and pouring of ordinary cast iron is 2-3 minutes. 6.如权利要求3所述的方法，其特征是离心铸机在浇注过程中的最合适的线速度为13—22米/秒。6. The method according to claim 3, characterized in that the optimum linear velocity of the centrifugal casting machine in the pouring process is 13-22 m/s.
CN95113322A 1995-10-31 1995-10-31 Centrifugal compound wear-resistant roll and its production method Expired - Fee Related CN1044574C (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101121996B (en) * 2007-09-21 2010-12-01 武汉钢铁(集团)公司 Outer material for centrifugal rolls
CN102389851A (en) * 2011-11-15 2012-03-28 吉林大学 High toughness bionic wear resistant grinding roller
CN102632217A (en) * 2012-05-10 2012-08-15 无锡布勒机械制造有限公司 Centrifugal casting mold for bimetallic composite chilled cast iron roll
CN105579158A (en) * 2013-09-25 2016-05-11 日立金属株式会社 Centrifugally cast composite roll for hot rolling
CN106076480A (en) * 2016-07-07 2016-11-09 江苏双发机械有限公司 A kind of roll squeezer alloy roller shell and processing method thereof
CN108624800A (en) * 2018-05-11 2018-10-09 铜陵市大明玛钢有限责任公司 A kind of chromium-copper abrading-ball production technology
CN108624801A (en) * 2018-05-11 2018-10-09 铜陵市大明玛钢有限责任公司 A kind of chromium-copper steel forging manufacturing process

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1032262C (en) * 1991-09-12 1996-07-10 川崎制铁株式会社 Outer material of roll and composite roll of centrifugal casting
CN2128558Y (en) * 1992-03-25 1993-03-24 上海重型机器厂 Grinding roll for coal grinding machine

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101121996B (en) * 2007-09-21 2010-12-01 武汉钢铁(集团)公司 Outer material for centrifugal rolls
CN102389851A (en) * 2011-11-15 2012-03-28 吉林大学 High toughness bionic wear resistant grinding roller
CN102632217A (en) * 2012-05-10 2012-08-15 无锡布勒机械制造有限公司 Centrifugal casting mold for bimetallic composite chilled cast iron roll
CN105579158A (en) * 2013-09-25 2016-05-11 日立金属株式会社 Centrifugally cast composite roll for hot rolling
CN106076480A (en) * 2016-07-07 2016-11-09 江苏双发机械有限公司 A kind of roll squeezer alloy roller shell and processing method thereof
CN108624800A (en) * 2018-05-11 2018-10-09 铜陵市大明玛钢有限责任公司 A kind of chromium-copper abrading-ball production technology
CN108624801A (en) * 2018-05-11 2018-10-09 铜陵市大明玛钢有限责任公司 A kind of chromium-copper steel forging manufacturing process

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