Steelcasting nozzles of calcined dunite

Conclusions Dunite steelcasting nozzles were subjected to testing with melts of the entire range of steel grades produced by the Nizhne-Tagil Metallurgical Combine.The nozzles gave normal casting and no difference was noted in the behavior and wear of unfired dunite and magnesite nozzles with channel diameters of 30 and 70 mm. The quality of rail steel in terms of surface flaws was the same for both nozzle types.In casting wheel and tire steels the experimental nozzles proved to be superior. Dunite nozzles are less susceptible to channel constriction but more susceptible to burn-through by oxygen.Channel encrustation was more prevalent in fired than in unfired dunite nozzles but less prevalent than in unfired magnesite nozzles, in addition to which wear was more rapid in the case of the latter.Translated from Ogneupory, No. 4, pp. 3–7, April, 1975.     

多级液柱喷射塔喷嘴雾化特性的研究

对5mm和8mm直径的喷嘴进行了液柱喷射试验,利用膜片采集法对塔内雾化液滴的滴径分布进行了研究。当5mm喷嘴的测点与喷嘴的垂直距离为1m,径向距离为0.3m,8mm喷嘴的测点与喷嘴的垂直距离为1m,径向距离为0.35m,喷嘴压力均为0.03MPa时,用对数-正态分布函数对5mm和8mm机械雾化式直射喷嘴的液滴滴径分布密度函数进行了拟合。     

Methods of improving the thermal-shock resistance of zircon nozzles

Conclusions The thermal-shock resistance of zircon nozzles can be increased by increasing the concentration of coarse fractions (3-0.5 mm) of briquette in the batch composition, incorporating silicon carbide, and excluding the clay.The use of zircon nozzles with an increased thermal-shock resistance improves the casting conditions on continuous steel casting plant, and increases the quality of the ingot surface in connection with the reduction in the number of crusts on the nozzles and the lower wear.Translated from Ogneupory, No. 3, pp. 46–50, March, 1970.     

Magnesia nozzles for high-speed steelcasting produced by vibropressure molding

Conclusions The article describes the design development of steelcasting nozzles with a channel diameter of 120 mm and the development of the production technology for these nozzles. With these nozzles the stopper and batching device functions efficiently during the casting of rimmed and semikilled steel. The configuration and diameter of the nozzle channel undergo no changes in the process.The increase in the channel diameter from 100 to 120 mm results in the average linear speed at which the ingot mold is filled increasing from 3.8 to 5.2 m/min; in a decrease by 32% in the pouring time per melt (from 25 to 17 min) so that the work load on the cranes is reduced and the handling capacity of the casting bay is increased; in a 15% increase in the durability of the ladle lining which gives a saving of 100,000 rubles/yr as a result of lower refractories consumption; and in less spoilage of billets and strip steel.The end result is that the net cost of the rolled product decreases by 0.35 ruble/ton.Translated from Ogneupory, No. 3, pp. 6–13, March, 1978.     

Research on rotary nozzle structure and flow field of the spinneret for centrifugal spinning

High-speed centrifugal spinning is a novel method of fabricating nanofibers by use of centrifugal force field. The neoteric designs and proper structural parameters of spinning nozzle will change the outlet velocity and velocity distribution uniformity of spinning solution, which could affect the quality of nanofibers. Four different spinning nozzles that can be used for high-speed centrifugal spinning are proposed. The flow of spinning solution in the different rotary nozzles is simulated based on the theoretical analysis. It can be found that the curved-tube nozzle is better for high-speed centrifugal spinning comparing with the velocity distribution of spinning solution in the four different spinning nozzles. The influence degree of the structure parameters of the curved-tube nozzle on the solution outlet-velocity is explored by orthogonal test method. The result shows that the curved-tube nozzle with an inlet diameter of 10 mm, conical transition pipe length of 3 mm, nozzle outlet diameter of 0.8 mm, curvature radius of 4 mm, and central angle of curved tube of 30°, can effectively enhance the outlet velocity of spinning solution. Finally, it is proved by centrifugal spinning experiment that the curved-tube nozzle after optimization can improve the morphology and quality of nanofibers.     

Influence of electric field interference on double nozzles electrospinning

The low production rate of electrospinning process may limit the industrial use of single needle system. To meet high yield requirement and uniform fibers, a bottom‐up multiple jets electrospinning nozzle was designed, each nozzle can emit 6–18 jets. The influence of electric field interference on jet path, membrane shape, and fiber morphology were investigated. Experiment finds that electrical field strength in the closer part of two nozzles is weakened because of electric field interference when the distance between two nozzles is 30 mm, making the jet hard to emit in this section, and closer part of electrospun fiber webs has fewer fibers. The spinning in far side part of two nozzles is similar to that of single nozzle. While in middle part of one nozzle, the jet path is short, elongation of jets smaller, the formed fibers thicker, solvent evaporation less sufficient. When the distance of two nozzles is increased to 50 mm, influence of electric field interference is weaker, the electrospun fiber web and average diameter of fibers are almost the same as that of single nozzle electrospinning. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Calcium alginate bead manufacture: With and without immobilised yeast. Drop formation at a two-fluid nozzle

Two models were developed to predict the size of drops of aqueous sodium alginate solution formed at a two-fluid nozzle. Experimental results revealed that actual drop sizes lay between the sizes predicted by the two models. Drop size was closely predicted by the volume mean of the two models. Several nozzles were tested and the influence of operating conditions on drop diameter was examined, with gas velocity and nozzle outer diameter having the largest effect. Only two nozzles would be needed to produce drops with diameters in the range 1–6 mm. The addition of yeast in amounts of up to 10% (w/w) had no effect on operation of the nozzles.     

Vibromolded and cast zircon nozzles for the pony ladles in continuous steelcasting

Conclusions It was shown that vibromolding and slip-easting techniques can be used to produce nozzles with a more homogeneous structure and higher thermal strength and density than those of industrial nozzles. The durability in service of the experimental nozzles was better than that of the industrial nozzles.Translated from Ogneupory, No. 3, pp. 20–24, March, 1977.     

A Novel Granulation Technology for Producing Spherical Wax Particles

A novel granulation technology for producing spherical wax particles that makes use of the insolubility of wax and water is developed. The granulation is stably performed in a granulator with a water‐cooling tower. The granulation process is analyzed and the influences of key factors on the process are studied. Experiments are carried out with 58^# semi‐refined wax and 70^# crystallitic wax in an experimental granulator which has 118 nozzles (D_i = 0.96 mm, D_o = 1.28 mm). The process capacity and the corresponding particle diameter are 55–60 kg/h and 4–5 mm, respectively. Using the modified correlation of Scheele and Meister, suitable operation flow rates and the corresponding particle diameters for different nozzles can be predicted. This technology has the following advantages: good particle shape with excellent fluidity, high process capacity and heat‐transfer efficiency, and a small space for the granulator. It is also suitable for producing spherical particles of other materials, which have similar physical properties to wax.     

Service of zircon-containing nozzles for use in continuous steel casting plant

Summary During service in the casting of killed steel, zirconium containing nozzles took on a zonal structure. The least changed zone of the nozzles is scarcely distinguishable from the refractories before service. The working zones during service are saturated with oxides of iron, manganese, aluminum, silicon and titanium, and their amount is strictly related to the compositon and quantity of deoxidant.Highly refractory nozzles of ZrO₂ and made of a mixture of ZrO₂ and zircon, possessing a higher apparent porosity, acquire a larger working zone than nozzles made of zircon with clay additions.The dense working zone is more rapidly formed in nozzles made of zircon and clay. The oxides adsorbed in the pores of the refractory contribute to the tightening up of the aperture of the nozzles.Zircon nozzles with clay additions used at the Donets Steel Mill proved to have excellent wear resistance and the lowest tendency to closing up when casting low-carbon killed steels and can be recommended for permanent use in continuous steel casting plants.     

喷雾流化床进行强吸水剂后处理的初步实验研究

用于妇女卫生巾、尿布等的高分子强吸水剂（合成树脂吸水剂）,要求有高的吸水倍率、高的吸水速率和低毒。为此,要求芯材和壁材除了一般团聚、包衣工序之外。还要进行化学后反应,而且不能发生显著的团聚现象。以下端直径1000mm、上端直径1400mm的间歇流化床为实验设备,设置三个底喷雾头（气流喷嘴,没有设置上喷嘴）,对该高分子吸水剂进行了工业试验,效果较为理想。     

Physicochemical processes during the contact of steel with casting nozzles

Conclusions The results of physicochemical processes taking place in casting nozzles depend on the content of the steel of chemically active components and the composition of the refractory. An examination of the phase diagram of the systems forming contact zones in the nozzles enabled us to obtain a nomogram for determining the degree of erosion or tightening up of the nozzles in the intermediate ladles as a function of the composition of the refractory material and the content of aluminum in the steel being cast.In order to explain the stable feed of metal from the intermediate ladels in continuous steel casting plant in the crystallizer we recommend the casting of rimmed steel through magnesite nozzles, killed steel with a content of less than 0.01% aluminum through zircon nozzles, and containing more than 0.01% aluminum through fireclay (35–40% Al₂O₃).Translated from Ogneupory, No. 6, pp. 33–38, June, 1973.     

文丘里引射反应器的喷嘴优化及压降分析

为解决黄磷脱砷系统中搅拌反应器反应不充分的问题,根据其工艺需求,研制出一种新型反应器--文丘里引射反应器,并将其用于贵州某黄磷厂的中试实验中.利用CFD数值模拟软件FLUENT的Realizable k-ε湍流模型和欧拉两相流模型,在经验公式范围内,对4种不同喷嘴出口直径(分别为6、8、10和12 mm)条件下的压降变化进行了研究和考察.结果显示,利用中试装置得到的相关实验数据与数值模拟结果基本吻合,说明数值模拟的结果是可靠的;随着喷嘴出口直径的增大,面积比减小,反应器所形成的压力比越大,驱动能力越强,同时工作效率也越高;喷嘴直径越小,产生的压力降越大,局部能量损失也越大,分散混合效果越好.根据模拟结果,为黄磷脱砷系统中文丘里引射反应器的工业放大设计提供了参考依据.     

Double-layer nonswirl nozzles for continuous casting machine pony ladles

Conclusions A method for chamotte nozzles with protection of the bore with a zirconia concentratebase layer has been developed. The life of the nozzles with the protective layer is at least as good as the zirconia-graphite ones. It is desirable to use the double-layer nozzles in place of zirconia and zirconia-graphite nozzles in teeming of various types of steel.The consumption of zirconia concentrate per unit of product is reduced by 10–12 times, which opens prospects of a significant increase in the volume of production of this new form of parts.Translated from Ogneupory, No. 1, pp. 54–56, January, 1986.     

Direct Ground Injection of livestock waste slurry to avoid ammonia emission

The aim of the project was to improve the slurry injection techniques for injecting animal waste slurries into the soil under Norwegian conditions. A new slurry application technique for grassland was therefore developed, by adapting well known methods of injecting a fluid into a solid or porous material. The injection nozzles had a diameter of 13 mm, and the liquid pressure in the nozzles was between five and eight bar, which was sufficient for the slurry to be injected 5 to 10 cm into the ground. The depth of the injection depended on the soil type and on the slurry pressure. Ammonia emission was reduced as compared with application through ordinary broadcasting, and with band spreading. The emission was also reduced if water was added to the slurry, or if the slurry solids were separated from the liquid before application.     

Wear behavior of ceramic nozzles in sand blasting treatments

Sand blasting nozzle is the most critical part in the sand blasting equipment. Ceramics being with high wear resistance have great potentials as the sand blasting nozzle materials. In this paper, monolithic B₄C and Al₂O₃/(W,Ti)C ceramic composite were developed to be used as nozzle materials. The wear behavior of nozzles made from these ceramic materials was compared by determining the cumulative mass loss and the erosion rates. Effect of the factors that influence the nozzle wear was investigated. Results showed that the hardness of the nozzles plays an important role with respect to its erosion wear in sand blasting processes. The monolithic B₄C nozzles being with high hardness exhibited lower erosion rates, while the Al₂O₃/(W,Ti)C nozzles with relative low hardness showed higher erosion rates under the same test conditions. Studies of the worn surface of the ceramic nozzles demonstrated that monolithic B₄C nozzles exhibited a brittle fracture induced removal process, while Al₂O₃/(W,Ti)C nozzles showed mainly a plowing type of material removal mode.     

甲醇制丙烯反应器喷嘴雾化性能的研究

雾化喷嘴系甲醇制丙烯（MTP）反应器内的关键反应物料分配构件,其雾化性能的优劣直接影响着对应催化床层覆盖区域内的传质和传热,从而影响到床层出口反应产物的分布。以反应器六级床层对应的雾化喷嘴为研究对象,分别以氮气（N₂）和水（H₂O）作为气相和液相模拟介质,通过“冷模”实验,考察了喷嘴气（液）流量与入口压力之间的关系,研究了喷嘴在不同气液比（G/L）下雾化粒径、雾化角度及雾化覆盖直径的变化规律。实验结果表明,喷嘴液相质量流量随着入口压力增大而逐渐增加,气相质量流量随着入口压力增加而迅速增加;当保持液相进料量为43.54 kg/h时,喷嘴由一次雾化变为二次雾化后,雾化角度由96.1°降至15.6°;当气液质量比G/L达到12.19时,雾化覆盖直径达到720mm,且雾滴的索泰尔平均粒径为16.3μm。     

The service of refractories in stream treatment of metal with continuous casting of the steel

Conclusions The service of monoblock stoppers, controlling nozzles, and submerged nozzles with stream blowing of the metal with gas was studied. The desirability of use of a monoblock stopper with a hole in the lower portion and a thread in the upper for treatment of the metal with gas in the intermediate ladle was concluded.The service of straight-through submerged nozzles under conditions of blowing was studied and means of increasing their life were noted.Translated from Ogneupory, No. 2, pp. 47–50, February, 1984.     

Improved quality zircon nozzles for continuous steelcasting

Conclusions An incorrect drying schedule is the main source of internal cracks in zircon nozzles. Cracking can be prevented either by drying the nozzles by an extended schedule (8 days at 30°C, 2 days at 50°C, and 1 or 2 days at 110°C) or by using ACPB instead of s. s.l. and drying the nozzles by a shorter schedule.Translated from Ogneupory, No. 5, pp. 15–19, May, 1977.