CN106345979A - Device and method for detecting and determining casting blank solidification end positions on basis of guide roller load - Google Patents
Device and method for detecting and determining casting blank solidification end positions on basis of guide roller load Download PDFInfo
- Publication number
- CN106345979A CN106345979A CN201610778769.5A CN201610778769A CN106345979A CN 106345979 A CN106345979 A CN 106345979A CN 201610778769 A CN201610778769 A CN 201610778769A CN 106345979 A CN106345979 A CN 106345979A
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- China
- Prior art keywords
- deflector roll
- solidification end
- casting blank
- end position
- load
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D2/00—Arrangement of indicating or measuring devices, e.g. for temperature or viscosity of the fused mass
Abstract
The invention discloses a device and a method for detecting and determining casting blank solidification end positions on the basis of guide roller load. According to the device and the method, multiple detection positions are set between frames for supporting guide rollers, each detection position is provided with a pressure testing element and a displacement element which are respectively connected with a processing unit, and the processing unit realizes comparison of changes of pressure and displacement sent from the different detection positions to determine the positions having the casting blank solidification ends. The detection elements are easy to set, data processing is simple and convenient, and the law of changes of pressure and displacement can be combined with casting blank solidification easily; further, online processing is achieved, the positions of the casting blank solidification ends, determined by the device and the method, are close to the reality, defects of the prior art are overcome, the positions can provide support for the pressing operation of a continuous casting machine, and problems about internal quality of the casting blanks can be solved.
Description
Technical field
The invention belongs to metallurgical process control technology field, it is related to one kind and casting blank solidification end is judged based on deflector roll load detecting
The device and method of end position.
Background technology
In continuous casting production process, high-temperature liquid state molten steel is formed with necessarily thick through crystallizer and two cold-zone continuous coo1ing
The strand of degree wick-containing, finally solidifies completely.Due to strand, in process of setting, molten steel there occurs solidification shrinkage, if solidification shrinkage
Cannot be completely supplementary, the internal flaws such as segregation, loose, shrinkage cavity and crackle can be formed in strand centre.In casting process
In, by several groups of frames, pressure is carried out to the strand with wick-containing before casting blank solidification end and compensate solidification shrinkage, and here
During, most crucial technology is how accurately to determine the solidification end position of strand.
Traditional method is to the solidification behavior founding mathematical models in casting process, according to steel grade performance parameter, pulling rate
Calculate the temperature field of strand with cooling parameter etc., thus predicting solidification end position.The shortcoming of this technology is due to solidifying wick-containing
Terminal position be Theoretical Calculation gained, the method for building up of its accuracy and model, steel grade parameter and boundary condition are closely related,
And lack direct detection foundation, it is difficult to checking in production.In continuous casting actual production process, answer because influence factor
Miscellaneous, the solidification end position of calculating is deviateed very greatly with actual, leads to pressure effect to fluctuate very big, does not reach production requirement.
Content of the invention
Present invention solves the problem in that providing a kind of dress judging casting blank solidification end position based on deflector roll load detecting
Put and method, provide for conticaster pressure and support, solve Inner Quality of Billet.
The present invention is to be achieved through the following technical solutions:
A kind of device being judged casting blank solidification end position based on deflector roll load detecting, the multiple frames supporting deflector roll are set
Put multiple detecting positions, load cell and displacement component, described load cell and displacement element are respectively provided with each detecting position
Part is connected with processing unit respectively, pressure that the more each detecting position of processing unit sends, change in displacement situation, judges to cast
The position of base solidification end.
Described detecting position is arranged at four corners of frame.
Described processing unit controls the deflector roll position of each frame always according to Displacement Feedback value, makes lower guide roll distance values
For strand natural cooling shrinkage value.
The depressing force value of feedback that described process unit sends according to load cell, obtains the regularity of distribution of deflector roll load,
Judge casting blank solidification end position: when casting speed stablizes constant, when mutation in the load of adjacent rack deflector roll, tentatively really
The position making existing mutation is solidification end position.
The Displacement Feedback value that described process unit sends according to displacement component, the strand of contrast different conditions passes through frame
When deflector roll load change, according to when deflector roll load slope further confirm that casting blank solidification end position.
A kind of method judging casting blank solidification end position based on deflector roll load detecting, sets between the frame of deflector roll supporting
Put multiple detecting positions, load cell and displacement component, described load cell and displacement element are respectively provided with each detecting position
Part is connected with processing unit respectively；
Process the depressing force value of feedback that unit sends according to load cell, obtain the regularity of distribution of deflector roll load, judge casting
Base solidification end position: when casting speed stablizes constant, when mutation in the load of adjacent rack deflector roll, primarily determine that appearance
The position of mutation is solidification end position；
The Displacement Feedback value that described process unit sends according to displacement component, the strand of contrast different conditions passes through frame
When deflector roll load change, according to when deflector roll load slope further confirm that casting blank solidification end position.
Described processing unit according to the judgement that load cell feeds back is:
When casting speed stablizes constant, when the deflector roll load of first frame loads very more than the deflector roll of second frame
When big, first frame is in casting blank solidification end position；When casting speed changes for speedup, when the deflector roll of certain frame is born
Carry from very little be changed into very big when, then this frame present position is casting blank solidification end position；When casting speed is to slow down change,
When certain frame deflector roll load from be changed into very little greatly very much when, then this frame present position be casting blank solidification end position.
Specifically it is judged as: when casting speed stablizes constant, when the deflector roll of first frame loads as second frame
Deflector roll load 2 times when, first frame is in casting blank solidification end position；When casting speed changes for speedup, when certain
When the deflector roll load of frame is increased to original 2 times, then this frame present position is casting blank solidification end position；Work as casting speed
When changing for slowing down, when the deflector roll load of certain frame is reduced to original 0.5 times, then this frame present position is coagulated for strand
Gu terminal position.
Described processing unit according to the judgement that load cell feeds back is:
Processing unit controls the deflector roll position of each frame by Displacement Feedback value, makes lower guide roll distance values for strand certainly
So cooling meat value；Progressively reduce deflector roll distance values, when deflector roll load is approximately slowly varying with quadratic linear, slope is by little change
Greatly, judge herein as casting blank solidification end position；Progressively reduce deflector roll distance values, deflector roll load is approximately quickly become with once linear
Change, slope is definite value, judge that strand solidifies completely.
Compared with prior art, the present invention has a following beneficial technique effect:
The device and method being judged casting blank solidification end position based on deflector roll load detecting that the present invention provides, is led in support
The frame setting load cell and displacement component of roller, by analyze pressure, change in displacement casting blank solidification Changing Pattern, according to
During casting blank solidification change, pressure, the corresponding suddenly change of displacement are thus tentatively being judged and determining whether to judge that strand coagulates
Gu the position of end: by record frame at strand from be changed into solidifying completely with wick-containing state when, deflector roll load change
Rule is primarily determining that casting blank solidification end position；Reduce roller space value by continuous, analysis deflector roll load change difference and
Reduction amount to confirm casting blank solidification end position with the relation of load change.
The device and method judging casting blank solidification end position based on deflector roll load detecting that the present invention provides, detecting element
Setting is simple, data processing easy it is easy to pressure, change in displacement rule can be combined with casting blank solidification, and can
Processed online, closing to reality, overcome defect of the prior art, can provide for conticaster pressure and support, solve casting
Base internal soundness.
Brief description
Fig. 1 is the load cell and displacement component scheme of installation in frame；
Fig. 2 is the load cell and displacement component schematic top plan view in frame；
The change schematic diagram of casting blank solidification end when Fig. 3 changes for casting speed；
Fig. 4 is deflector roll load variation diagram when casting speed is different；
Fig. 5 is the ratio change schematic diagram of deflector roll load and deflector roll distance values when strand does not solidify completely；
When Fig. 6 solidifies completely for strand, deflector roll load and the ratio value changes of deflector roll distance values are illustrated.
Wherein, 1 is deflector roll, and 2 is strand, and 3 is load cell, and 4 is displacement component, and 5 is support.
Specific embodiment
With reference to specific embodiment, the present invention is described in further detail, described be explanation of the invention and
It is not to limit.
Referring to Fig. 1, Fig. 2, a kind of device judging casting blank solidification end position based on deflector roll load detecting, supporting deflector roll
In 1 multiple frames, multiple detecting positions are set, load cell 3 and displacement component 4 are respectively provided with each detecting position, described
Load cell 3 is connected with processing unit respectively with displacement component 4, pressure that the more each detecting position of processing unit sends, position
Move situation of change, judge the position that casting blank solidification end exists.
Specifically, described detecting position is arranged at four different directions of frame, and each direction arranges a detecting position；?
Four positions of frame are respectively mounted load cell and displacement component, thus obtaining Displacement Feedback value and depressing force value of feedback；Logical
Cross the deflector roll position that Displacement Feedback value controls each frame, make lower guide roll distance values be strand natural cooling shrinkage value.
The depressing force value of feedback that described process unit sends according to load cell, obtains the regularity of distribution of deflector roll load,
Judge casting blank solidification end position: when casting speed stablizes constant, when mutation in the load of adjacent rack deflector roll, tentatively really
The position making existing mutation is solidification end position.
The Displacement Feedback value that described process unit sends according to displacement component, the strand of contrast different conditions passes through frame
When deflector roll load change, according to when deflector roll load slope further confirm that casting blank solidification end position.
A kind of method judging casting blank solidification end position based on deflector roll load detecting, operates including following:
It is respectively mounted load cell and displacement component in four positions of frame, thus obtaining Displacement Feedback value and depressing force
Value of feedback；
Control the deflector roll position of each frame by Displacement Feedback value, so that lower guide roll distance values is received for strand natural cooling
Contracting value；
Record frame load cell depressing force value of feedback, obtains the regularity of distribution of deflector roll load, tentatively judges casting blank solidification
Terminal position: when casting speed stablizes constant, analyze adjacent rack deflector roll loading condition, occur when adjacent rack deflector roll loads
During mutation, primarily determine that solidification end position.Concrete determination methods are: when the deflector roll load of first frame is more than second machine
When the deflector roll load of frame is very big (being such as, that the deflector roll of second frame loads 2 times), first frame is in casting blank solidification end
Position；When casting speed changes for speedup, when certain frame deflector roll load from little be changed into very big when (be increased to original 2
Times when), then this frame present position be casting blank solidification end position.When casting speed is to slow down change, when certain frame
Deflector roll load by very big change very little into when (when being reduced to original 0.5 times), then this frame present position be casting blank solidification end
Position.
Change the deflector roll position of each frame by displacement component value of feedback, when the strand of contrast different conditions passes through frame
The Changing Pattern of deflector roll load, the regularity of distribution difference of analysis deflector roll load, further confirm that casting blank solidification end position.Specifically
Method is: progressively reduces deflector roll distance values, when deflector roll load is approximately slowly varying with quadratic linear, slope changes from small to big, and can sentence
Fixed be casting blank solidification end position herein；Progressively reduce deflector roll distance values, deflector roll load is approximately quickly changed with once linear, tiltedly
Rate is almost definite value, can determine that strand solidifies completely.
With reference to Fig. 3, during casting speed change, change is also followed in solidification end position；When casting speed becomes hour, solidification end
End position shortens, and when casting speed becomes big, solidification end position is elongated.
With reference to Fig. 4, by when before solidifying to after solidification, deflector roll load being obviously reduced and subsequently substantially keeps shelf position occurs
Very little fluctuates, so when deflector roll load can preliminary judgement be strand by substantially diminishing greatly and subsequently substantially keeping very little to fluctuate herein
Solidifying terminal position.
With reference to Fig. 5, when deflector roll distance values taper into, because this region strand does not solidify completely, deflector roll load is near
Seemingly slowly varying with quadratic linear, slope changes from small to big, and can confirm as strand and coagulate terminal position on the basis of accompanying drawing 4.
With reference to Fig. 6, when deflector roll distance values taper into, because this region strand solidifies completely, coefficient of elasticity very big and
It is nearly a steady state value, deflector roll load is approximately quickly changed with once linear, and slope is almost definite value.
Example given above is to realize the present invention preferably example, the invention is not restricted to above-described embodiment.This area
Technical staff made according to the technical characteristic of technical solution of the present invention any nonessential interpolation, replacement, belong to this
The protection domain of invention.
Claims (9)
1. a kind of the device of casting blank solidification end position is judged it is characterised in that supporting deflector roll based on deflector roll load detecting
In multiple frames, detecting position is set, load cell and displacement component be respectively provided with each detecting position, described load cell
It is connected with processing unit respectively with displacement component, pressure that the more each detecting position of processing unit sends, change in displacement situation,
Judge the position that casting blank solidification end exists.
2. as claimed in claim 1 based on deflector roll load detecting judge casting blank solidification end position device it is characterised in that
Described detecting position is arranged at four different directions of frame, and each direction arranges a detecting position.
3. as claimed in claim 1 based on deflector roll load detecting judge casting blank solidification end position device it is characterised in that
Described processing unit controls the deflector roll position of each frame always according to Displacement Feedback value, makes lower guide roll distance values for strand certainly
So cooling meat value.
4. as claimed in claim 1 based on deflector roll load detecting judge casting blank solidification end position device it is characterised in that
The depressing force value of feedback that described process unit sends according to load cell, obtains the regularity of distribution of deflector roll load, judges strand
Solidification end position: when casting speed stablizes constant, when mutation in the load of adjacent rack deflector roll, primarily determine that appearance is prominent
The position becoming is solidification end position.
5. as claimed in claim 4 based on deflector roll load detecting judge casting blank solidification end position device it is characterised in that
The Displacement Feedback value that described process unit sends according to displacement component, the strand of contrast different conditions passes through deflector roll during frame and bears
The change carrying, further confirms that casting blank solidification end position according to when deflector roll load slope.
6. a kind of the method for casting blank solidification end position is judged it is characterised in that supporting deflector roll based on deflector roll load detecting
Multiple detecting positions are arranged on multiple frames, load cell and displacement component be respectively provided with each detecting position, described pressure measurement
Element is connected with processing unit respectively with displacement component；
Process the depressing force value of feedback that unit sends according to load cell, obtain the regularity of distribution of deflector roll load, judge that strand coagulates
Gu terminal position: when casting speed stablizes constant, when mutation in the load of adjacent rack deflector roll, primarily determine that appearance mutation
Position be solidification end position；
The Displacement Feedback value that described process unit sends according to displacement component, leads when the strand of contrast different conditions is by frame
The change of roller load, further confirms that casting blank solidification end position according to when deflector roll load slope.
7. as claimed in claim 6 based on deflector roll load detecting judge casting blank solidification end position method it is characterised in that
Described processing unit according to the judgement that load cell feeds back is:
When casting speed stablizes constant, when the deflector roll load of first frame is very big more than the deflector roll load of second frame
When, first frame is in casting blank solidification end position；When casting speed changes for speedup, when the deflector roll load of certain frame
From very little be changed into very big when, then this frame present position is casting blank solidification end position；When casting speed is to slow down change, when
From when being changed into very little greatly very much, then this frame present position is casting blank solidification end position for the deflector roll load of certain frame.
8. as claimed in claim 6 based on deflector roll load detecting judge casting blank solidification end position method it is characterised in that
Described when casting speed stablizes constant, when the deflector roll that the deflector roll of first frame loads as second frame loads 2 times, the
One frame is in casting blank solidification end position；When casting speed changes for speedup, when the deflector roll load of certain frame increases
During for original 2 times, then this frame present position is casting blank solidification end position；When casting speed is to slow down change, when certain
When the deflector roll load of individual frame is reduced to original 0.5 times, then this frame present position is casting blank solidification end position.
9. as claimed in claim 6 based on deflector roll load detecting judge casting blank solidification end position method it is characterised in that
Described processing unit according to the judgement that load cell feeds back is:
Processing unit controls the deflector roll position of each frame by Displacement Feedback value, makes lower guide roll distance values be that strand is naturally cold
But shrinkage value；Progressively reduce deflector roll distance values, when deflector roll load is approximately slowly varying with quadratic linear, slope changes from small to big, and sentences
Fixed be casting blank solidification end position herein；Progressively reduce deflector roll distance values, deflector roll load is approximately quickly changed with once linear, tiltedly
Rate is definite value, judges that strand solidifies completely.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610778769.5A CN106345979B (en) | 2016-08-30 | 2016-08-30 | A kind of device and method that casting blank solidification end position is judged based on deflector roll load detecting |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610778769.5A CN106345979B (en) | 2016-08-30 | 2016-08-30 | A kind of device and method that casting blank solidification end position is judged based on deflector roll load detecting |
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| CN106345979B CN106345979B (en) | 2018-05-11 |
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Cited By (1)
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| CN108380837A (en) * | 2018-01-31 | 2018-08-10 | 中冶连铸技术工程有限责任公司 | A kind of method of determining slab specific location solidification geomery |
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