DE2120799C - Process for regulating the lance spacing in the oxygen inflation process according to the sound intensity of the blown noise - Google Patents

Description

4. The method according to claim 1, characterized in that it can be optimally regulated.

that the reference value in the empty converter is preferably used during the

is measured. a ₅ state of sufficient slag foaming

5. The method according to any one of claims 1 to 4, the pre-batch measured. The one characterized in this slag that a desired state measured lowest or possibly moderate or stronger Sc! Back foaming due to the lere value of the sound intensity of the blowing noise, an additional propoitionality factor is taken into account to determine the proportionality factor which is taken into account. ₃ o following Schmölze used.

Another possibility is to use the reference value in the state of ignition or just before the

Measure ignition.

Another possibility is to use the reference 35 value to measure in the empty converter.

If less or more foam is desired, an additional

The invention relates to a method for regulating the; rather proportionality factor taken into account.
Lance spacing in the oxygen inflation process according to the measures according to the invention

Determination of the characteristic time-curve course, 40 the operational and process-related circumstances (reference variable) the sound intensity of the blowing noises, which leads to a change in the amplitude of the see. The noise level. These operational influences

The purpose of the present procedure is to provide a safe result for example through * the changing and simple automation of the oxygen inflation inner shape of the converter and the associated process, especially in connection with a 45 mcrelated resonance effect, which occurs with electronic computers, to reach. increasing wear of the refractory lining

There are already many preliminary results for achieving this goal.

beat has been made. An overview from the Another influence is the operational change

1964 comes from the Siemens magazine change of the mouth part of the converter, namely (Siemens-Zeitschrift, 1964, Issue 4, pp. 214 to 217). From 50 due to wear-related enlargement of the mouth end The regulation diameter and through the construction of a steel cinder block has a large number of measurable variables Lance spacing according to the sound intensity approach on the muzzle, the gap between always encouraged investigations (see mouth and exhaust hood or exhaust gas boiler verStahl and Eisen, 1968, pp. 613 to 621), although it changes.

In many melts it was possible to reduce the slag level according to the sound intensity under control to be named at the nozzle. After all, it can hold, these results cannot yet be satisfactory. approach are narrowed, which also affects the measured value

For a more precise automatic implementation of the sound intensity is of influence.
Fresh process has also been proposed, according to which the reference value is preferably measured fresh conditions by combined measurements of the exhaust gas temperature and the sound intensity in the state of sufficient slag foaming. This slag state depends on the blow molding (German Offenlegungsschrift 1 533 898). Like driving out of one and from the inner shape of the converter. more recent work emerges (control engineering pra- The degree of slag foaming, which at the beginning xis, 1969, p. 107 to 113, especially p. Ill and 113), 65 of a converter trip are described as sufficient, it is not possible with the current state of the art, is not the same that applies to a converter that is more heavily worn after the sound measurement alone. It is part of the knowledge about the relationships between the converter before the invention that these time-changing input

liquid in all ampl

effect curve equally, namely near / u obtained deepest value of the sound intensity

proportional. Therefore, their hmining, which is in the middle of the course of the soil I

Purpose read Regeins is necessary, reproduced on the proposed partial picture. The lower part shows

Genetic solution possible. _{5 den a (jf reason dep So} | _{,. Werle ün line} through the right

For a better understanding, the mode of action should be a controlled lane distance curve. From regcl-

and the advantages of the method according to the invention for technical reasons - protection of the electrical

an Han «-: the one in l · ι g. 1 reproduced schematic facilities - was the successor of the lance

Presentation explained below: the distance to the sound curve made in stages.

In I- 'S- I' St on the ordinate, the sound intensity _l0 was preferred in areas of higher lance

and on the abscissa - from the point of intersection - correspondingly higher sound curve distances -

the Av 'ι, en starting - to the left of the lance spacing cuts - larger steps and when reaching lower

and it .: II right? the blowing time. In the right halite of the lance spacing of smaller steps is given like this

Figure: ι the time curve course of the sound intensity particularly clearly on the basis of the central partial image

of i'i.-i successive batches schematically 15 of FIG. 2 in the period from the 7th to the 10th minute

dargL-! It. It shows the reference number I can be recognized. The order of the stages depends

versef.

rentl ^; r total bubble time of a melt. At the age of 3, zugmoiors is off. In this example, these could

the r irvenstück of the blowing time section is called. Levels are no longer reproduced in detail,

for.! ι ■ for the pre-batch (previous batch) 20 In the 11th and 16th minute, the actual-

the -land of sufficient slag foaming - lance spacing largely true to the graded target

reici α orden is, while '2 the course of the curve is the distance.

shows the melt following curve 1 (melt). According to a further preferred method,

The course of the melt on the basis of curve 1 shows the proportionality factor at the time of the igniter

that: h found the ignition in the blowing period from r ₀ to Z _{1 of} the 25 or shortly before ignition. This process

Ger. ^ ,, dipegel is above the control range, so rensweise can be used particularly advantageously

^daL: he must be set Lanz distance L _maz. if spontaneous freevents between pre-batches

In (i- time from t _x to r, the lance spacing will develop and batch make it impossible to use the lowest

spa: -iid the decrease in time of curve 1 from L _max value of the sound intensity from the precharge for the

on 'humiliated. Curve 1 then falls to I ₃ 30 to use the following scheme. Such spontaneous

because ·; from so that at I ₃ the lance distance L _mln er events are z. B. cleaning the sound measuring tube,

reici f will. The actual value measured at / _{a of} the sound - the removal of the steel slag approach from the

mtt: - ität corresponds exactly to that of the precharge, the readjustment of the sound curve screech ^:

haiknen lowest value of the sound curve 3. Furthermore, etc. One must take into account that the so

ren course of the curve 1 is at / the lowest value _like 35 reference value obtained for calculating the Proportiio-

the sound intensity is reached, which for the calculation of the nality factor does not match the expected low-

Pro ^ ortionality factor for the regulation of the lancetest value of the sound curve is identical, but a

absiandes is used in the next melt. A multiple of this. Through ongoing control

The lance distance remains between I ₃ and / ₅ despite the change from batch to batch - ideally by means of an electrical

further decrease of the sound curve unchanged to 40 tronic computers - this is the multiplication factor

LnKH, since the lower control range has been reached. Can only be easily determined from t _s. It is particularly worth mentioning

the lance will be in accordance with the rise of that in the case of the measurement of the noise just before

ScnaU curve raised to L _n. the ignition is expediently always the same

For the course of the lance run with the following lance spacing and a constant oxygen

the melt - according to sound curve 2 - the flow rate is then to be maintained. This can be

the proportionality factor corresponding to the low - particularly advantageous through the use of an electrical

Most value of curve 1 changed, as shown in the ruffled calculator on the left as part of an ignition program

Half of the fig. 1 using the dashed line.

is. Through this measure, the "characteristic state" for the reference variable

a number of other possibilities are conceivable,

placed, although the intensity of the blowing noise is similar to the recording of the blowing noise in the empty

(actual actual value of the reference variable) for den- verter or the application of another defined

has changed the same process state. th sound source that is also outside the converter

F i g. 2 shows a practical embodiment could be arranged.

a melt produced in the 110 t LD converter. There 55 The particular advantages of the invention exist

were 101.7 t Thomas pig iron with 3.8% coal in that both in a simple manner with the help of a

material, 0.33% silicon, 0.57% manganese, 1.83% electrical regulator between the sound indicator instrument

Phosphorus and 0.034% sulfur and 24 t scrap char- and lance train engine as well as more comfortable, through

greed. During the blowing process, 8.24 t of lump lime were removed using a modern computer, a fast and

600 kg of limestone and 1.8 t of ore were added. The majority of the industrial claims were made by Sauer

material consumption was 5640 Nm ³ with an incidentally insufficient regulation of the lance spacing

broke Bhr.czcil of 20.1 minutes, and the achieved base of a single measuring device - the high one

The final temperature was 165O ^U C. The analysis of the casting reliability shows - is possible. Thereby wcr-

A sample of the unquenched cast steel showed 0.17% of the time-variable, on the amplitude deflection

Carbon, 0, Λ>% manganese, 0.071% phosphorus and 65 acting influencing factors are properly taken into account, see above

0.026% sulfur. The course of the sound intensity that the method is reproducible.

The blowing noise is shown in the upper part of FIG. 2 Dar- Of course, in addition, upon request

placed. The one from an electronic calculator to a more dry or frothy one

Slag are driven. In this case, additional a corresponding proportionality factor is taken into account. This way v.lrd achieved that the lance dem The course of the sound curve follows tighter or more delayed.

It has been shown in practice that the proposed Regulation is fast enough to avoid spraying or ejection. These good results have been even with a non-stepless regulation of the lance spacing, such as B. in. Fig. 2, achieved.

1 sheet of drawings,

Claims (3)

Add lying slag to the lance at. As can be seen from the claims: concluding observations of this reference, the lance travel is regulated via the 1. Procedure for regulating the lance spacing No sound measurement in its current form Oxygen on blowing process according to the 5 bar. Time curve course (reference variable) of the sound The invention has set itself the task of a Verintensität the blowing noises, thereby indicating the danger at which the lance distance indicates that before the fresh start finally according to the sound intensity of the blower Batch the sound intensity of the blowing noise is regulated. in the case of a characteristic state (reference value) io. This object is measured according to the invention and the relationship is resolved from the fact that before the fresh start of each batch the measured value (reference value) for reference variable; Sound intensity of the blowing noises with a character Proportionality factor is measured when regulating the lanceolistic state (reference value) and that distance in accordance with the time curve relationship between the measured value (reference value) and (Reference variable) is included in the reference variable. 15 reference variable as proportionality «factor in re- 2. Vt ^"f Ahren according to claim 1, characterized marked rules of Lanzena'ustandes accordance with the Zeitzeichnei that the reference value during the Zustan- curve path (command) is received in the Führungsdes Schlackenschäumigkeit sufficient in size. The resulting action flow is measured in the pre-batch. The control loop is thus determined by the proportionality 3. The method according to claim 1, characterized in that _ao factor is determined which indicates the extent by which the reference value is to be corrected in the state of the ignition. After the dens or shortly before the ignition is measured. the corrected reference variable is then the lance