WO2012106837A1 - Smokeless spheroidization processing method - Google Patents

Abstract

A smokeless spheroidization processing method for producing nodular cast iron. Disposed in the center of a side of a rectangular or square steel pipe (13) are multiple pressure-adjusting throughholes (17) or a pressure-adjusting slit (19). Melted alloy liquid of a nodulizer of rare earth, magnesium, silicon, and iron (18) comprising Mg ≤ 20%, Si ≤ 65% and RE ≤ 3% is injected into the steel pipe (13) for solidification and cooling; a rod having a pressing head (1) fixes the nodulizer of rare earth, magnesium, silicon, and iron (18), encased in the rectangular or square steel pipe (13), inside of a spheroidization ladle (7); the rod having a pressing head (1) has a weight iron and is hung by a hook (16) of an electric motor-powered hoisting device, or the rod having a pressing head (1) is connected by a first bolt (8) on a steering shaft (2), the steering shaft (2) being disposed on a lever (4) that pivots on a lever pivot shaft, the lever pivot shaft being a third bolt and nut (12) disposed on an upright post and position-fixing and measuring scale (6). Ladle-flushing method is adopted to precisely control the spheroidization reaction time and to enable smokeless spheroidization. The absorption rates of Mg, RE, and Si are high after the reaction, thereby improving the manufacturing environment of the nodulizer preparation process and application process, and reducing production costs while enhancing product quality.

Description

 Smokeless spheroidization treatment method

 The present invention relates to a method for producing a spheroidizing agent and a spheroidizing treatment device, and more particularly to a method of using a bulk rare earth magnesium silicate spheroidizing agent in combination with a treatment apparatus for a smokeless spheroidizing treatment.

Background technique

 Rare earth magnesium ferrosilicon alloy is widely used as a spheroidizing agent in enterprises producing ductile iron castings. Rare earth magnesium ferrosilicon alloy spheroidizing agent is the most widely used ball refining agent at home and abroad, but in its traditional production process, it has high energy consumption, large melt loss and serious environmental pollution. The traditional spheroidizing agent has low absorption rate due to magnesium. It is added in a large amount. For a long time, domestic and foreign technicians have made unremitting efforts to study the in-package spheroidization process technology and the production process of rare earth magnesium silicon spheroidizer. Book

 At present, in the production process of spheroidizing with rare earth magnesium ferrosilicon as the spheroidizing agent, when the iron temperature is above 1480 ,, the spheroidizing treatment package is in the state of continuous use of red hot pack, and the Mg content is At 8%, the spheroidization reaction condition is aggravated with the increase of temperature, and strong magnesium light or even molten iron splash occurs. As a result, the absorption rate of the effective elements Mg and RE decreases, resulting in the late decline of the spheroidized molten iron, spheroidization. The level is down. The traditional solution is to add a certain amount of SiCa alloy to increase the content of Ca in the smelting of the spheroidizing agent to alleviate the explosive reaction. Increasing the SiCa alloy undoubtedly increases the production cost. 2 The content of Mg in the spheroidizing agent is controlled to about 8% or 8% to alleviate the reaction. 3 In the dam of the rare earth magnesium silicon spheroidizing agent put into the ladle, the iron filings are covered and solidified, and the pouring riser and the broken iron block are added into the bag to reduce the reaction temperature of the molten iron in the package. 4 After the spheroidizing agent is put into the bag and the ferrosilicon is inoculated, the perlite slag agent is covered thereon or the iron plate is covered thereon. Although the above measures are effective for controlling the severe reaction of magnesium alloy, the reaction is over, the molten iron is cooled more, and the surface of the molten iron is more scum. The stability of the spheroidization reaction is affected by the temperature of the molten iron. The effective elements Mg, RE and Si The fluctuation range of the absorption rate is large; when the high-temperature molten iron of the cupola smelting is high in the sulphur content of the original molten iron before spheroidization, only the addition amount of the spheroidizing agent is increased and the content of RE and Ca in the spheroidizing agent is increased, and The current increase in the amount of Mg in the spheroidizing agent under high temperature treatment conditions is very limited.

The Chinese invention patent number CN101029367A, which I have applied for, is entitled "Spheroidizing Treatment Device and Spheroidization Treatment Process" and two patent applications entitled "Spheroidizing Agent Production Method" in the publication No. CN101509084A, all of which have been patented and solved. The problem of violent reaction and low effective element absorption rate when spheroidizing in the bag is also solved, and the reaction of the rare earth magnesium silicate spheroidizing agent in the melting process is severe, the burning loss is large, and the composition of the spheroidizing agent alloy is segregated. The problem that needs to be improved: The spheroidization treatment device is used for spheroidization treatment, and the structure of the dam-type spheroidization treatment package is required. In order to put the rare earth magnesium silicate spheroidizing agent and the inoculant into the dam, the dam must be There is sufficient height, for example, the newly built 1000kg spheroidal bag has a height of 23cm, and the 3⁄4 of the dam's twist increases the position of the explosion point of the spheroidizing agent boiling boiling reaction, which is not conducive to the absorption of effective elements and the purification of molten iron. Controlling the spheroidization reaction ^ Control the position of the struts according to the condition of the treatment package, to achieve magnesium-free) t smokeless spheroidization requires a longer time. The dam inside the bag is easy to hit after being spheroidized: 3⁄4, damaged, these problems will affect the stability of the spheroidizing treatment. It also increased the workload of repairing ladle.

Summary of the invention

 The object of the present invention is to provide a smokeless spheroidizing agent, which is combined with a spheroidizing treatment device to solve the problem of strong reaction and low absorption rate of effective elements when spheroidizing in the bag, accurately controlling the spheroidization reaction time and improving product quality. Reduce production costs, make full use of resources, and significantly improve the production environment of the spheroidizing agent production process and use process.

In order to achieve the above object, a plurality of pressure-regulating through holes 17 or pressure-regulating slits 19 are formed in the middle of one side of the rectangular or square-shaped steel pipe 13. For the rectangular steel pipe, the pressure-regulating through-hole 17 or the middle of the one end surface of the small area should be opened. Pressing the slit 19, injecting the molten rare earth magnesium silicate spheroidizing agent liquid containing 3⁄4^20%, containing 51655% and containing RE 3% into a rectangular shape with the pressure regulating through hole 17 or the pressure regulating slit 19 Or in the square steel pipe 13, after it is solidified and cooled, a block-shaped spheroidizing agent having a rectangular or square steel pipe 13 as an outer liner and open at both ends is obtained, in order to further control the reaction speed of the spheroidizing agent in the pipe, the same The steel plate with the same wall thickness of the steel pipe is spliced to block a part of the opening of the rectangular or square steel pipe 13 to reduce the contact surface of the high-temperature molten iron with the bulk spheroidizing agent, and control the reaction start time and reaction state of the spheroidizing agent. The spheroidizing treatment device using the Chinese Patent Publication No. CN101029367A as the "spheroidizing treatment device and the spheroidizing treatment process" is provided with a pole indenter 1 which is movable in the spheroidizing treatment package and can be fixed at a desired position. The underside of the ram of the strut 1 is In a plane, the refractory part of the strut indenter 1 is made of rebar and wire, and the strut head 1 can withstand the repeated impact of high-temperature molten iron and the spheroidizing agent with 20% magnesium content. In the case of the impact, the column and the fixed ruler in the column and the positioning scale 6 are integrally connected, and the up and down movement positioning 3 is provided at the end of the positioning scale, and the balance iron 5 is suspended at the other end of the pressing bar 4. The spheroidizing agent of the outer-lining rectangular or square steel pipe 13 is a compact rectangular parallelepiped having a small volume, and the position of the explosion point of the melting reaction of the whole rare earth magnesium silicate spheroidizing agent is low, and the spheroidization reaction in the horizontal direction is performed. Conducive to the absorption of effective elements and the purification of molten iron. The spheroidizing package can be repaired into a flat spheroidized bag or a dam-type spheroidal bag with a lower dam. For the flat-bottomed spheroidizing package, as shown in Figure 1, Figure 2 and Figure 3, the overall lining of rectangular or square steel pipes will be The rare earth magnesium silicon spheroidizing agent 18 is provided with one side of the pressure regulating through hole 17 and placed at the center of the adjacent spheroidizing package, and the ram head 1 is pressed on the whole rare earth magnesium silicate spheroidizing agent 18 of the outer lining rectangular or square steel tube. , put the ferrosilicon inoculant on the side close to the wall. For the lower spheroidal package of the dam, as shown in FIG. 4 and FIG. 5, the whole rare earth magnesium silicate spheroidizing agent 18 of the rectangular or square steel pipe is opened with one side of the pressure regulating through hole 17 and the adjacent spheroidized bag wall. The other end is placed close to the dam, and the ram head 1 is pressed on the whole rare earth magnesium silicate spheroidizing agent 18 of the outer lining rectangular or square steel tube, and the ferrosilicon inoculant is placed at both ends of the reaction port and near the wall of the package. . When the pressure regulating through hole 17 or the pressure regulating slit 19 is not opened, after the molten iron is washed into the spheroidizing bag, the spheroidizing agent at the two ports of the whole rare earth magnesium silicon spheroidizing agent 18 which is lined with a rectangular or square steel pipe is the same as the high temperature molten iron. After the contact, the boiling boiling reaction begins. When the molten spheroidizing agent is boiled, the pressure of the boiling reaction increases as the depth increases, the frequency becomes slower, and the boiling of the molten iron is intensified; as shown in FIG. 3 and FIG. After the pressure regulating through hole 17 or the pressure regulating slit 19 is opened, the spheroidizing agent melt boiling reaction can be sprayed out by the pressure regulating through hole 17 or the pressure regulating slit 19, thereby shortening the path of the spheroidizing agent boiling boiling reaction and reducing the pressure. The reaction situation tends to be flat. It is known from the experiment that for the outer lining rectangular or square steel pipe 13 having a length greater than 25 cm 吋, the pressure regulating through hole 17 is opened on the outer lining rectangular or square steel pipe 13, and the diameter of the pressure regulating through hole 17 is 8 to 14 visibly. The effect is that when the length of the outer lining rectangular or square steel pipe (13) is more than 25cm, the pressure regulating seam 19 is opened on the outer lining rectangular or square steel pipe 13, and the slit width of the pressure regulating slit 19 should be 2~4ιTM, and the molten iron temperature is treated. Higher, tune The opening area of the pressure through hole 17 or the pressure regulating slit 19 should be small, and when the temperature of the treated molten iron is low, the opening area should be large. The above-mentioned strut indenter 1 can press the strut by connecting the first bolt 8 of the steering shaft 2 on the pressing bar 4 on which the third bolt and the nut 12 of the positioning rod 6 rotates as a rotating shaft The head 1 is placed on the upper rare earth magnesium silicate spheroidizing agent 18 of the outer lining rectangular steel pipe and fixed; the ram head 16 with the weight iron 15 can also be suspended by the hook head 16 of the motor driven lifting device, the struts The indenter 1 is based on the first bolt 8 of the steering shaft 2 on the pressure bar 4 rotating on the third bolt and the nut 12 on the column, and is coupled to the strut head 1 on the strut head 1 The weight iron 15 is placed on the whole rare earth magnesium silicon spheroidizing agent 18 of the outer lining rectangular steel pipe, and after the spheroidization reaction is finished, the struts head 1 is separated from the spheroidizing bag; The rod indenter may also be connected to the strut indenter 1 by welding the positioning shaft sleeve 25 at the upper end of the outer side of the spheroidizing bag 7 as shown in FIG. 7 , and the nut connected to the positioning shaft sleeve 25 by the thread at the end of the positioning handle 23 . 24 mating, the threaded portion of the end of the locating shank 23 is fastened through the positioning shaft sleeve 25 to tighten the ram head 1 The position of the strut indenter 1 in the spheroidizing bag 7 is now adjusted; the strut indenter 1 is movable and can be fixed at the required position, and the strut indenter 1 is to be lined with a rectangular or square steel tube of the whole rare earth magnesium silicon The iron spheroidizing agent 18 is fixed underneath; the bottom surface of the ram of the struts of the struts is a plane, and the refractory part of the lining of the struts 1 is made of round steel and steel bars and wires. As shown in Fig. 7, the strut indenter 1 is connected by the positioning shaft sleeve 25, and the strut head 1 moves with the spheroidizing bag 7 when the molten iron spheroidizing treatment is performed.

 In order to further improve the utilization ratio of the rare earth element, the first bolt 8 of the steering shaft 2 on the pressure bar 4 on which the third bolt and the nut 12 of the column and the positioning scale 6 are used as the rotating shaft and the rotating rod 4 are coupled to the strut head 1 Or the method of suspending the strut head 1 with the counterweight iron 15 by the hook 16 of the motor drive and the three types of the strut indenter 25 connected by the outer upper end of the spheroid pack 7 In the spheroidizing treatment method, an overall rare earth magnesium silicon having a rare earth element content of 33% with a rectangular or square steel tube lined inside the whole magnesium ferrosilicon spheroidizing agent 20 as shown in Figs. 8 and 9 was designed and fabricated. Ferroalloy 21, integral magnesium ferrosilicon spheroidizing agent 20 lined with rectangular or square steel tube and integral rare earth magnesium ferrosilicon alloy 21 with external rare earth element content of 33% of rectangular or square steel tube, the direction of the exposed opening of the alloy is the same, by welding The integral rare earth magnesium ferrosilicon alloy 21 with a rare earth element content of 33% of the outer or outer rectangular steel tube is connected with the composite outer rectangular or square steel tube 22 for accommodating the whole magnesium ferrosilicon spheroidizing agent 20, and will be melted. The whole magnesium ferrosilicon spheroidizing agent 20 alloy liquid is injected into the composite outer lining rectangular or square steel tube 22 for solidification and cooling; in order to accelerate the cooling of the spheroidizing agent alloy liquid, the rectangular or square arrangement of the spheroidizing agent alloy liquid is arranged. A cooling iron is added between the steel pipes to prevent segregation of the components of the spheroidizing agent; the molten iron is washed into the spheroidizing package, and after the spheroidizing reaction is started, the rectangular or square steel pipe is lined up in the reaction time of less than 50% at the end of the entire spheroidizing reaction process. The whole rare earth magnesium ferrosilicon alloy 21 with a rare earth element content of 33% begins to participate in the spheroidization reaction, effectively supplementing the required rare earth element content.

 Since the rectangular or square steel pipe 13 has a regular appearance, the L* is arranged upwardly and the rare earth magnesium iron spheroidizing agent alloy liquid produced by the one-step production of the ferrosilicon alloy smelted by the submerged arc furnace or the secondary remelting method of the electric furnace is adopted. Pouring into it, due to the rectangular or square steel tube 13 and the cooling iron, the cooling and condensing of the spheroidizing agent alloy liquid is accelerated, the chemical composition segregation of the spheroidizing agent is reduced, and the integral spheroidizing alloy of the rectangular or square steel tube is lined. It does not need to be broken and sieved, which is convenient for handling.

 The spheroidization process is as follows:

a. Put the whole thin seven-magnesium silicate spheroidizing agent 18 with rectangular or square steel tube as required into the spheroidizing package. After reaching the predetermined position, the movable strut head 1 is pressed thereon and fixed;

 b. In the spheroidized package, 7 put in the ferrosilicon inoculant;

 c, molten iron washed into the spheroidizing package 7 to carry out spheroidization reaction;

 d. After the spheroidization reaction is completed, the strut head 1 is separated from the spheroidizing bag 7.

The invention has the beneficial effects of solving the problem that the reaction is severe and the absorption rate of the effective element is low when the spheroidizing treatment is carried out in the bag, and the molten iron is cooled less, and the magnesium-free smokeless spheroidization treatment can be realized. The spheroidization reaction time can be precisely controlled. When the temperature of the molten iron water fluctuates <30 ° C, the spheroidization reaction time is less than 5 seconds. The conventional spheroidizing agent containing Mg 8%, RE 5% and Si 41% is lined with a rectangular or square steel pipe 13 , and has a built-in spheroidizing agent containing 5% Mgl, containing RE1% and containing 54% of Si. That is, the whole rare earth magnesium silicate spheroidizing agent 18 of the outer-lined rectangular or square steel pipe produced by the one-step production or the electric furnace secondary remelting method is compared with the conventional rare earth magnesium silicate spheroidizing agent, and the production cost of the product can be reduced by 20 %~30%, the weight of the whole rare earth magnesium ferrosilicon spheroidizing agent 18 containing lining rectangular or square steel tube during spheroidization can be reduced by 25~30% compared with the traditional spheroidizing agent; When the spheroidizing temperature is changed from 1450 ° C to 1578 ° C, the amount of the whole rare earth magnesium silicate spheroidizing agent 18 of the rectangular or square steel tube is not changed, the spheroidization reaction time is constant, and the spheroidization result is obtained. No effect, overcome the problem of increasing the addition amount of spheroidizing agent with the increase of spheroidizing temperature when the spheroidizing treatment of traditional process; using the column and positioning ruler when adding spheroidizing agent after spheroidizing treatment 6 The third bolt and the nut 12 are the steering shaft 2 on the pressure bar 4 on which the rotating shaft rotates. The manner in which the first bolt 8 is coupled to the strut indenter 1 or the strut head 16 of the motor-driven device suspends the strut indenter 1 having the counterweight iron 15 The whole rare earth magnesium silicate spheroidizing agent 18 of the steel pipe or the whole rare earth magnesium ferrosilicon alloy 21 of the rectangular or square steel pipe with a rare earth element content of 33% is iron and iron bonded to the bottom surface of the strut head 1 and pressed into the iron In water, the content of magnesium and rare earth elements required for supplementation is supplemented; the production environment of the spheroidizing agent production process and the use process is improved. Compared with the closest Chinese invention patent publication number CN 101029367A, the name is "spheroidizing treatment device and spheroidization treatment process", under the same chemical composition of the same rare earth magnesium ferrosilicon spheroidizing agent and the same spheroidization treatment temperature, The spheroidization reaction time of the whole rare earth magnesium silicate spheroidizing agent 18 with a rectangular or square steel tube is more precise, shortening the time of the smokeless spheroidization reaction, and the absorption rates of the effective elements Mg, RE and Si are high, for the rare earth The conventional rare earth magnesium silicate spheroidizing agent with element RE content of 2~8% can reduce the RE content of rare earth elements by 50~75% by using this process _; when the spheroidization treatment requires a small amount of magnesium, it can be added. Join in time.

BRIEF DESCRIPTION OF THE DRAWINGS:

 1 is a first bolt of a steering shaft 2 on a pressure bar 4 that rotates a third column of bolts and nuts 12 on a column and a positioning rod 6 with a monolithic rectangular steel pipe; 8 is a cross-sectional view of the spheroidal spheroidal pack 7 placed in a flat bottom spheroidal pack.

 Fig. 2 is a plan view showing the input of the entire rare earth magnesium silicon spheroidizing agent 18 having a rectangular or square steel pipe lined in a flat-bottomed spheroidizing bag 7 and pressed into the ram head 1.

 Fig. 3 is a cross-sectional view showing the injection of the entire rare earth magnesium silicon spheroidizing agent 18 having a rectangular or square steel pipe lined in a flat-bottomed spheroidizing bag 7 and pressing it into the strut head 1.

Fig. 4 is a plan view showing the injection of the integral dilute I: magnesium silicon spheroidizing agent 18 having an outer lining rectangular or square steel tube into the dam type spheroidizing bag 7 and pressing it into the strut indenter 1. Fig. 5 is a view showing a method of placing a monolithic rare earth magnesium iron spheroidizing agent 18 having a rectangular-lined steel pipe with a hook head 16 of a motor-driven lifting device for suspending a strut head 1 having a counterweight iron 15 A cross-sectional view of the package 7.

 Figure 6 is a view of the monolithic rare earth magnesium silicate spheroidizing agent 18 having a rectangular or square steel tube lined with a pressure regulating slit 19. Figure 7. The upper end of the flat-bottomed spheroidizing bag 7 is welded to the positioning shaft bushing. 25 Connecting the strut indenter 1 The cross-sectional view of fixing the whole rare earth magnesium ferrosilicon spheroidizing agent of the rectangular or square steel pipe to the bottom of the bag.

 Fig. 8 is a cross-sectional view showing the entire rare earth magnesium ferrosilicon alloy 21 in which the rare earth element content of the outer-lined rectangular or square steel pipe is 33%, in the entire magnesia spheroidizing agent 20 of the composite outer-lining rectangular steel pipe 22.

 Fig. 9 is a left side view of the monolithic magnesium ferrosilicon spheroidizing agent 20 of the composite outer lining rectangular steel pipe 22, which is provided with an outer lining ferrosilicon alloy 21 having a rare earth element content of 33% of a rectangular or square steel pipe.

 DESCRIPTION OF REFERENCE NUMERALS: 1 is a strut indenter, 2 is a steering shaft, 3 is a vertical moving position, 4 is a pressing bar, 5 is a balanced iron, 6 is a column and a positioning ruler, 7 is a spheroidizing bag, 8 is the first Bolt, 9 is the second bolt, 10 is the first bolt and nut, 11 is the second bolt and nut, 12 is the third bolt and nut, 13 is the outer rectangular or square steel tube, 14 is the whole rare earth magnesium silicon iron ball Chemical agent, 15 is the weight iron, 16 is the hook head of the lifting equipment, 17 is the pressure regulating through hole, 18 is the whole rare earth magnesium silicon iron spheroidizing agent with outer rectangular or square steel tube, 19 is the outer rectangular or square The pressure regulating joints on the steel pipe, 20 is the whole magnesium ferrosilicon spheroidizing agent, 21 is the whole rare earth magnesium ferrosilicon alloy with the rare earth element content of 33% of the rectangular or square steel pipe, and 22 is the composite outer rectangular or square steel pipe, 23 For positioning the handle, 24 is a nut for welding on the positioning shaft sleeve, and 25 is a positioning shaft sleeve.

detailed description:

 The implementation of the present invention will be further described with reference to the accompanying drawings: The rectangular or square steel tube 13 lining the whole rare earth magnesium ferrosilicon spheroidizing agent 14 plays a key role in controlling the reaction state and reaction time of the rare earth magnesium alloy; When the bag is spheroidized, it is tightly surrounded by the refractory surface of the spheroidal bag bottom of the dam, the dam and the bottom surface of the strut head 1, and the other side is covered with ferrosilicon inoculant, which delays the outer lining rectangle. Or the melting speed of the square steel pipe 13, therefore, the wall thickness of the outer-lining rectangular or square steel pipe 13 is selected to be 2 to 4 to meet the needs of the spheroidizing treatment. When the spheroidizing temperature is greater than 1480 Ό and the spheroidizing reaction time is long, When using a flat-bottomed spheroidizing bag, the wall thickness of the upper limit is selected, and if necessary, outside the outer rectangular or square steel pipe 13, the two reaction port faces are coated with a refractory paint to delay the melting. The outer-lining rectangular or square steel pipe 13 used above may also be made of a cast iron material and cast. It is known from the experiment that in order to prevent the spheroidizing treatment time from being too short and the reaction is too intense, the height of the whole rare earth magnesium silicate spheroidizing agent 14 placed in the spheroidizing treatment package is < 12 (^ is appropriate, and when it exceeds 12 cm, it should be selected. The structure of the rectangular steel pipe, the size of the rectangular steel pipe facet should be 12cm. The outer lining rectangular or square steel pipe 13 used above and the steel plate with the same wall thickness of the steel pipe are spliced to block the opening of the rectangular or square steel pipe 13 at both ends. The materials used are all carbon steel and are not coated.

Example 1: Under the chilling condition of a cold-air cupola, the melting rate is 2 tons/hour, and the whole thin-magnesium-silicon spheroidizing agent 18 with a lining square steel pipe as shown in the drawing is used in combination with the column and positioning. The third bolt and the screw 12 on the scale 6 are placed in the dam type spheroidizing bag 7 in the manner of the bolt 8 of the steering shaft 2 on the pressure bar 4 on which the rotating shaft rotates, and the weight of the molten iron per package is 500 kg. The red hot pack is continuously used. The temperature of the molten iron in the tapping tank is 1480, and the sulfur content of the original molten iron is 0.062%. Excluding the whole rare earth magnesium silicon iron spheroidizing agent M with outer square steel pipe Mgl6%, containing RE2% and containing Si54%, the weight of the whole rare earth magnesium silicate spheroidizing agent 18 put into the outer lining square steel tube accounts for 1.2% of the weight of the treated molten iron, and 0.4% of the 72SiFe inoculant package is added, secondary silicon钡 钡 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1

 Embodiment 2: Under the medium frequency electric furnace smelting condition, the whole rare earth magnesium silicon spheroidizing agent 18 with the outer lining rectangular steel pipe shown in FIG. 3 is used together with the third bolt and the nut 12 on the column and the positioning scale 6 The first bolt 8 of the steering shaft 2 on the rotating shaft 4 of the rotating shaft is placed in the flat-bottomed spheroidizing bag 7 in a manner of connecting the strut indenter 1 with a weight of 1000 kg per package, and the tap water temperature of the electric furnace is 1578 ° C. The original molten iron has a sulfur content of 0.028%, and the whole rare earth magnesium silicon iron spheroidizing agent 14 contains Mgl5%, contains RE1% and contains Si54%, and the weight of the whole rare earth magnesium silicon iron spheroidizing agent 18 is 0.8 of the weight of the treated molten iron. %, 72SiFe inoculant package added 0.4%, secondary silicon germanium was added 0.2%, in the case of not covering iron filings and perlite, the spheroidization reaction time was 1 minute 56 seconds, the spheroidization reaction was stable, no molten iron splash Sampling was performed 12 minutes after the end of the spheroidization reaction, and the spheroidization level was 2 levels.

Claims

Claim 1. A smokeless spheroidizing treatment method for producing ductile iron, the first part of which is characterized by a spheroidizing agent: a rectangular or square steel tube (13) is used to open a pressure regulating through hole (17) or a middle portion of a side of one side thereof. Pressure seam (19), for rectangular steel pipe, a pressure-regulating through hole (17) or a pressure-regulating slit (19) should be opened in the middle of a small end face, and the melted Mg 20%, Si-containing 65% and RE-containing 3% of the rare earth magnesium silicate spheroidizing agent alloy liquid is injected into the rectangular or square steel pipe 03) with the pressure regulating through hole (17) or the pressure regulating slit (19), and is solidified and cooled in the spheroidizing alloy liquid. A cooling iron is added between the rectangular or square steel pipes arranged in combination; the second part of the feature is a spheroidizing device: a pressing bar rotating with a shaft and a third bolt and a nut GZ on the positioning scale (6) as a rotating shaft (4) The first bolt (8) of the upper steering shaft (2) is coupled to the strut head (1) in such a manner that the strut head (1) is movable and can be fixed at a desired position, and the strut head is fixed (1) The bottom surface of the indenter is a flat surface, and the refractory part of the strut indenter (1) is a skeleton welded by a rebar or a wire; the column and the positioning The column and the positioning ruler in the ruler (6) are integrally connected, the upper and lower movement positioning (3) is arranged at the end of the positioning ruler, and the balance iron (5) is suspended at the other end of the pressure bar (4);  The spheroidization process is as follows:  a. Put the whole rare earth magnesium silicate spheroidizing agent (18) with a rectangular or square steel pipe lined into the spheroidizing treatment package (7) to reach the predetermined position, and press the movable struts (1) And fixed on it;  b. Putting a ferrosilicon inoculant in the spheroidizing package (7);  c, molten iron into the spheroidizing package (7) for spheroidization reaction;  d. After the spheroidization reaction is finished, the rod indenter U) leaves the spheroidizing package (7)  2. The spheroidizing treatment method according to claim 1, wherein the rare earth magnesium silicate spheroidizing agent alloy produced by one-step production of ferrosilicon alloy smelted by a submerged arc furnace or secondary remelting by electric furnace is poured into a rectangle or Square steel pipe 03).  3. The spheroidizing treatment method according to claim 1, characterized in that the outer-lining rectangular or square steel pipe (13) is made of cast iron material and is manufactured by a casting method.  4. The spheroidizing treatment method according to claim 1, characterized in that, when the length of the outer-lining rectangular or square steel pipe (13) is greater than 25 cm, a pressure-regulating through hole (17) is formed on the outer-lining rectangular or square steel pipe (13). The diameter of the pressure regulating through hole (17) is 8 to 14 mm.  5. The spheroidizing method according to claim 1, wherein when the length of the outer-lining rectangular or square steel pipe (13) is greater than 25 cm, a pressure-regulating slit (19) is opened on the outer-lining rectangular or square steel pipe (13). The gap width of the pressure regulating slit (19) is 2~4 6. The spheroidizing method according to claim 1, characterized in that the hook head (16) of the motor-driven lifting device is used to suspend the strut head (1) having the counterweight iron (15). With the column and positioning scale (6) h, the third bolt and the nut (13 is the first bolt (8) of the steering shaft (2) on the rotating shaft (4) of the rotating shaft, and the supporting head (1) is connected. Spheroidizing treatment. 7. The spheroidizing method according to claim 1, wherein after the spheroidizing treatment, the spheroidizing agent is added, and the third bolt and the nut (12) on the column and the positioning scale (6) are used. The rotating shaft of the rotating shaft (4) h the steering shaft (2) of the first bolt (8) is coupled with the strut indenter (1) in a manner that will add the required outer lining rectangular or square steel tube to the overall thinness I: Magnesium silicate spheroidizing agent (18) or an overall thinning magnesium ferrosilicon alloy (21) with a thin element content of a rectangular or square steel tube lined with iron and iron bonded to the bottom of the struts of the struts U) The hot metal 屮, complements the effective element hinge and thin: the content of h element. 8. The spheroidizing treatment method according to claim 6, characterized in that the hook head of the motor-driven lifting device is used when the spheroidizing agent needs to be added after the spheroidizing treatment (1© suspension has a weight iron (1) The ram of the ram (1), the required amount of the outer lining of the rectangular or square steel tube of the whole rare earth magnesium silicate spheroidizing agent (18) or the outer lining of rectangular or square steel tube with a rare earth element content of 33% The whole thin magnesium ferrosilicon alloy (21) is iron and iron bonded to the bottom surface of the strut head (1), which is pressed into the molten iron to supplement the required effective elemental magnesium and rare earth elements.  9. The spheroidizing method according to claim 1, characterized in that the struts of the struts (23) are connected by using a spheroidal package (7) on the outer upper end of the welding positioning shaft sleeve (25). The thread of the part is matched with the nut (24) welded on the positioning shaft sleeve (25), and the threaded portion of the end of the positioning handle (23) is passed through the positioning shaft sleeve (25) to fasten the rod indenter (1). The positioning handle (23) is used to adjust the position of the strut indenter (1) in the spheroidizing bag (7); the strut indenter (1) can be moved and fixed in the required position, the strut indenter ( 1) Fixing the whole rare earth magnesium silicate spheroidizing agent (18) with a rectangular or square steel tube lining underneath; the bottom surface of the ram of the struts (1) is a plane, and the ram of the struts (1) The lining refractory part is a skeleton welded by round steel and steel and iron wire.  10. The spheroidizing treatment method according to claim 1, 6 or 9, characterized in that the whole magnesium ferrosilicon spheroidizing agent (3⁄4) is provided with an outer lining rectangular or square steel tube having a rare earth element content of 33%. Rare earth magnesium ferrosilicon alloy (21), integral magnesium ferrosilicon spheroidizing agent (GO) lined with rectangular or square steel tube and integral rare earth magnesium ferrosilicon alloy (21) with external rare earth element content of 33%, the alloy is exposed The direction of the crucible is the same, and the composite of the whole rare earth magnesium ferrosilicon alloy (21) with the rare earth element content of 33% of the rectangular or square steel tube and the composite outer layer of the magnesia iron spheroidizing agent (20) is welded or squared. When the steel pipe (22) is joined, the molten molten magnesium spheroidizing agent (20) alloy liquid is injected into the composite outer lining rectangular or square steel pipe (22) to be solidified and cooled, and is rushed into the spheroidizing alloy liquid. Additional cooling iron is added between the rectangular or square steel tubes; the molten iron is flushed into the spheroidizing package, and after the spheroidization is started, the rare earth element content of the outer-lined rectangular or square steel tube is less than 50% of the reaction time in the last spheroidization reaction process. 33% overall The rare earth magnesium ferrosilicon alloy (21) begins to participate in the spheroidization reaction to effectively supplement the required rare earth halogen content.