CN205241736U - RH refining device - Google Patents

Abstract

The utility model discloses a RH refining device, the device is including ladle (1) and vacuum tank (2), through parallel ascending dip pipe (3) and decline dip pipe (4) intercommunication between ladle (1) and vacuum tank (2), the cross section of ascending dip pipe (3) and decline dip pipe (4) is the ellipse. The equivalent diameter of the device through changing dip pipe cross sectional shape improvement RH dip pipe, fundamentally solves the problem that the molten steel circulation is difficult to obtain the improvement.

Description

A kind of RH purifier

Technical field

The utility model belongs to RH refining production field, and particularly, the utility model relates to RH purifier.

Background technology

RH refinery practice is to develop the earliest two German company Ruhstahl of this technique and the name of Heraeus lifeName, it is a kind of steel secondary refining technique for the production of high-quality steel. Whole molten steel metallurgical reaction is to have refractory lining at blockVacuum tank in carry out. The bottom of vacuum tank is two dip pipes with refractory lining, and hot-bending pipe is equipped with on top, and gas is by hot bendingPipe, watercooling elbow through gas cooler to vacuum pump system. Before steel treatment, first dip pipe is immersed to pending ladle molten steelIn. In the time that vacuum tank vacuumizes, the pressure reduction in atmospheric pressure and the vacuum tank of molten steel surface forces molten steel to flow in dip pipe. WithTwo dip pipes that vacuum tank is communicated with, one is tedge, one is down-comer. Because tedge is constantly blown into argon gas to molten steelOr nitrogen, be blown into that when gases are heated, they expand, thereby drive molten steel constantly to rise, argon gas, the hydrogen, one of flowing through in vacuum tank molten steelThe gases such as carbonoxide are pumped under vacuum state. Degassed molten steel is because the relation of gravity flows into ladle through down-comer again, justThis constantly circulates repeatedly. Meanwhile, enter the molten steel of vacuum tank under environment under low pressure state, also carry out a series of metallurgical reaction,Such as reaction between carbon and oxygen. For meeting steel grade requirement, accurately controlling molten steel composition, conventionally, RH also needs to carry out Alloying Treatment in processing.Ferroalloy materials, through high hopper, weighing bucket, belt feeder, vacuum charging system, alloy chute, passes through true under vacuum stateDead slot enters molten steel, completes alloying technology.

RH ladle trolley, being subject to bag position to receive the pending molten steel being come by traveling crane, is wrapped rear ladle trolley and is reached heat preserving agentDrop into position, add aluminium slag, or directly open to the processing position of vacuum tank below, by manually judging steel liquid level, subsequently jackingLadle is to predetermined altitude. Carry out thermometric, sampling, determine oxygen and survey the operations such as thickness of slag layer. Ladle is continued jacking by hydraulic cylinder, will be trueThe dip pipe of dead slot immerses molten steel and arrives the predetermined degree of depth. Meanwhile, rising dip pipe is blown into argon gas with the flow of being scheduled to. WithDip pipe and immerse molten steel completely, vacuum valve is opened, and vavuum pump starts. Vavuum pumps at different levels enter according to the predefined curve of bleedingRow work. Vacuum dehydrogenation processing: at the appointed time and under regulation low pressure condition, continue to carry out circulating degasification operation, to reach dehydrogenationDesired value. Vacuum decarburization processing (low-carbon (LC) or Ultra-low carbon grade molten steel): circulating degasification by certain time to reach decarburizationDesired value. In decarbonizing process, the carbon in molten steel and oxygen reaction form carbon monoxide and discharge by vavuum pump. As oxygen in steelContent is inadequate, can provide oxygen by top rifle oxygen blast. When decarburization finishes, molten steel carries out deoxidation by adding aluminium. After deoxidation of molten steel, closeGold material adds vacuum tank by vacuum charging system. Molten steel is carried out thermometric, determines oxygen and definite chemical analysis. Steel treatment is completeFinish, vacuum valve cuts out, and vacuum pump system is termination of pumping successively, and vacuum tank is pressed again simultaneously, and again in atmospheric pressure state, ladle drops toLadle trolley. Rising dip pipe switches to nitrogen flushing by Argon automatically. Ladle trolley is opened to adding heat preserving agent station, and Argon is fed silk and thrownEnter heat preserving agent. Ladle trolley reach molten steel accept across, driving ladle handling to continuous caster turret.

RH method is a kind of important secondary refining method, has that treatment cycle is short, production capacity is large, refining effect is good, holdsThe series of advantages such as easy to operate is applied widely in STEELMAKING PRODUCTION. Up to the present, RH is by original single taking offGas equipment changes that to comprise vacuum decarburization, oxygen decarburization, powder injection desulphurization, temperature-compensating, uniform temperature and composition etc. multi-functional intoExternal refining equipment. And along with the progress of technology and the expansion of refining function, aspect production ultra-low-carbon steel, showing and showingThe superiority of work is the outer treating apparatus of requisite stove in modernization steel mill.

Along with Chinese large-sized iron and steel enterprise is constantly from the advanced RH refining equipment of external introduction and technology, we find respectivelyThe difference of the RH main equipment of producer is very little, operating technology, and consumption indicators and last guarantee value are all more or less the same, moreConcern is how to bring into play on the capacity utilization of RH. At present, Iron and Steel Enterprises in China generally adopts high-efficient continuous casting technology equipment, continuous castingMachine pulling rate is more and more faster, has occurred the situation of continuous casting production link wait external refining link, has limited the production effect of conticasterRate. The development of smelting iron and steel clean steel is requiring to increase molten steel furnace external refining ability always. The RH of Baosteel steel-making at present processes than being53% left and right, the external surging RH of iron and steel enterprise processes ratio generally higher than 70%, and what have even reaches more than 90%. Visible, improveThe disposal ability of RH and process ratio, is the Iron and Steel Enterprises in China steel that produce choice goods, and replace imported maximizedly meets domestic marketNeed, realize Business Economic Benefit and maximize and the optimized effective way of social benefit. The disposal ability that improves RH is iron and steelA urgent job in metallurgy industry.

Utility model content

The purpose of this utility model is, a kind of RH purifier is provided, and this device is by changing dip pipe cross sectional shapeThe equivalent diameter that improves RH dip pipe, fundamentally solves the problem that molten steel circulation amount is difficult to be improved.

For achieving the above object, the utility model has adopted following technical scheme:

A kind of RH purifier, described device comprises ladle 1 and vacuum tank 2, between described ladle 1 and vacuum tank 2, passes throughParallel rising dip pipe 3 and decline dip pipe 4 are communicated with, it is characterized in that, described rising dip pipe 3 and decline dip pipe 4Cross section is ellipse.

Circular flow formula:

$Q=7.43\×{10}^3\×G^{1/3}\×D^{4/3}\×{\left(\ln \frac{P_1}{P_2}\right)}^{1/3};$

Q: circulation (kg/min), G: lift gas flow (mark (m³/min))

D: dip pipe diameter (cm), P1: atmospheric pressure (pa), P2: vacuum pressure (pa)

Decarbonization rate formula: $\frac{dc}{dt}=-K_c\×(C-C_{eq});$

$K_c=\frac{Q}{V}\×\frac{a_k}{Q+a_k};$

K_cFor decarburization coefficient (L/min), C_eqFor the equilibrium concentration (%) of carbon in molten steel, the cumulative volume (m that V is molten steel³)，QFor the cycle rate (m of molten steel³/min)，a_kFor decarburizing reaction volume transmission quality coefficient (m³/min)。

Be directly proportional to the equivalent diameter of dip pipe from the velocity of circulation of the known molten steel of above-mentioned circular flow formula, dip pipeLarger its velocity of circulation of equivalent diameter is just larger, and the flow of molten steel is just larger. Decarburization COEFFICIENT K_cBe directly proportional to molten steel circular flow,And decarbonization rate and decarburization COEFFICIENT K_cBe directly proportional, therefore adopt large diameter dip pipe to have very large side to improving RH refining effectHelp.

The utility model is by traditional circular cross-section being changed into ellipse cross section dip pipe, and the equivalent that improves dip pipe is straightFootpath, increases circular flow, improves decarburization efficiency and ensures for production Ultra-low carbon provides technique, shortens refining time, reduces in ladleDead band, improves refining effect. The utility model effectively improves circular flow by changing domestic existing RH dip pipe shape, fromImprove decarburization efficiency, reduce dead band in ladle, shorten the advantages such as processing time and reach.

Brief description of the drawings

Fig. 1 is the utility model RH purifier structural representation;

Fig. 2 is A-A sectional view in Fig. 1;

Fig. 3 is oval and the comparison of circular dip pipe velocity of circulation;

Fig. 4 is oval and the comparison of circular dip pipe decarbonization rate;

Reference numeral: 1, ladle; 2, vacuum tank; 3, rising dip pipe; 4, decline dip pipe.

Detailed description of the invention

With the drawings and specific embodiments, the utility model is described in further detail below.

Embodiment 1

As depicted in figs. 1 and 2, a kind of RH purifier, described device comprises ladle 1 and vacuum tank 2, described ladle 1 HeBetween vacuum tank 2, be communicated with by parallel rising dip pipe 3 and decline dip pipe 4, it is characterized in that, described rising dip pipe 3Be ellipse with the cross section of decline dip pipe 4.

Performance test

Test steel grade is IF steel, under identical process conditions, for different dip pipe equivalent diameters and different argon gas streamAmount is carried out lower test. RH adopts dark carbonization treatment mode, processes before measurement thickness of slag layer, and that dip pipe inserts molten steel face is following 450～500mm. If thermometric T≤1610 DEG C for the first time after ladle puts in place, should first chemical heating. [C] >=0.06% or [O] when ladle arrivesWhen≤300ppm, should first oxygen blast force decarburization, then transfer nature decarburization to. Dark decarburization is complete, adds aluminum shot final deoxidizing, and according toDesired value is adjusted aluminium content. Oval and circular dip pipe velocity of circulation and decarbonization rate are compared, and result is as Fig. 3 and TuShown in 4. The molten steel circular flow of circular dip pipe is far smaller than the molten steel circular flow of oval dip pipe as can be seen from Figure 3Amount, and in RH, decarburization COEFFICIENT K_cBe directly proportional to molten steel circular flow, and decarbonization rate and decarburization COEFFICIENT K_cBe directly proportional. Adopt ellipseAfter circle dip pipe, as shown in Figure 4, the decarbonization rate of oval dip pipe is higher than circle as can be seen from Figure 4 in the variation of RH decarbonization rateThe decarbonization rate of shape dip pipe. Along with its effect of increase of time is more obvious.

It should be noted last that, above embodiment is only unrestricted in order to the technical solution of the utility model to be described. To the greatest extentPipe has been described in detail the utility model with reference to embodiment, will be understood by those skilled in the art that, to this practicalityNovel technical scheme is modified or is equal to replacement, does not depart from the spirit and scope of technical solutions of the utility model, itsAll should be encompassed in the middle of claim scope of the present utility model.

Claims (1)

1. a RH purifier, described device comprises ladle (1) and vacuum tank (2), described ladle (1) and vacuum tank (2) itBetween be communicated with by parallel rising dip pipe (3) and decline dip pipe (4), it is characterized in that, described rising dip pipe (3) and underThe cross section that falls dip pipe (4) is ellipse.