Metal deforming – With use of control means energized in response to activator... – Metal deforming by use of roller or roller-like tool element
Patent
1994-06-10
1996-05-28
Crane, Daniel C.
Metal deforming
With use of control means energized in response to activator...
Metal deforming by use of roller or roller-like tool element
72 92, 72 103, 72 104, B21B 3710
Patent
active
055200370
DESCRIPTION:
BRIEF SUMMARY
This application is a 35 U.S.C. 371 of PCT/DE92/00989 filed Nov. 26, 1992.
BACKGROUND OF THE INVENTION
The invention relates to a roll stand adjusting method for adjusting the desired roll force and desired roll gap of a roll stand.
Such a method is known, for example, from the Siemens brochure "Ideas for the process automation of steel wide hot strip trains". Computing is performed according to this prior art via complex model equation systems, matching of model parameters being undertaken iteratively.
SUMMARY OF THE INVENTION
The present invention minimizes the expenditure on computing the desired roll force and desired roll gap.
Before rolling a strip of a prescribed quality from an expected material hardness and before a relative desired pass reduction given from a pass schedule, the desired roll force is computed taking account of stand-specific and/or material/specific roll force fitting terms and with simplification by means of a simple arithmetic combination, and then the desired roll gap is computed, with simplification by means of a simple arithmetic combination, from the desired delivered thickness given by the relative desired pass reduction, the stand modulus and the desired roll force, taking account of a zero-point correction, a temperature correction and, as the case may be, a roll gap fitting term, and the stand is subjected to the desired roll force and the desired roll gap.
To be specific, it has surprisingly become evident that despite the complexity of the rolling process the model equations can be linearized with sufficient accuracy. As a result, the model for computing the desired quantities becomes extremely simple, since the model equations feature only the four fundamental arithmetic operations of and no complicated functions such as, for example, logarithms or trigonometric functions.
In this case, the desired roll force and desired roll gap are advantageously computed by computing the desired roll force (F*) in accordance with the formula
The fitting terms of the model equations can be corrected automatically if during rolling the actual roll force, the actual roll gap and the actual rotational speed of the stand are measured, and the actual delivered thickness of the strip is determined from the actual rotational speed taking account of the forward slip, and the actual delivered thickness is compared with the actual delivered thickness expected on the basis of the model taking account of the actual roll force and the actual roll gap, and on the basis of this comparison a correction factor is computed for one of the stand-specific parameters, for example for the zero-point correction, or if during rolling the actual roll force is measured and the actual pass reduction is determined, and on the basis of these actual quantities a new stand-specific fitting term is determined and a correction factor is determined for the fitting term by means of the comparison of the newly calculated fitting term with the previously used fitting term. However, it is preferred to weight the correction factors with a confidence factor which takes account of the accuracy of the measured actual values, so that non-recurring measurement errors are not "perpetuated" in the fitting terms.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages and details emerge from the following description of an exemplary embodiment with the aid of the drawings.
FIG. 1 shows a diagrammatic roll stand with indication of the most important quantities of rolling technology, and
FIG. 2 shows the connection of the roll stand to the process control.
DETAILED DESCRIPTION
In accordance with FIG. 1, the aim is for a strip 1, which has a width B and is subjected on the input side to the tension ZE and on the output side to the tension ZA, to be rolled from the starting thickness HE to the desired delivered thickness HA*. For this purpose, the rolls 2, 2', whose radius is R, are subjected to the roll force F and the rotational speed n, it being the case, furthermore, that the roll gap S between the rolls 2, 2' is adjuste
REFERENCES:
patent: 4274273 (1981-06-01), Fapiano et al.
patent: 4576027 (1986-03-01), Yoshida et al.
patent: 4648256 (1987-03-01), Wakamiya
patent: 5047964 (1991-09-01), Lalli
Siemens: Process Automation of Hot-Strip Mills.
Crane Daniel C.
Siemens Aktiengesellschaft
Tolan Ed
LandOfFree
Roll stand adjusting method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Roll stand adjusting method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Roll stand adjusting method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-779428