AU2006284201A1 - Method for thickness regulation during a hot-rolling process - Google Patents

Method for thickness regulation during a hot-rolling process Download PDF

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Publication number
AU2006284201A1
AU2006284201A1 AU2006284201A AU2006284201A AU2006284201A1 AU 2006284201 A1 AU2006284201 A1 AU 2006284201A1 AU 2006284201 A AU2006284201 A AU 2006284201A AU 2006284201 A AU2006284201 A AU 2006284201A AU 2006284201 A1 AU2006284201 A1 AU 2006284201A1
Authority
AU
Australia
Prior art keywords
rolling
gage
automatic
accordance
strip
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
AU2006284201A
Other versions
AU2006284201A2 (en
Inventor
Olaf Norman Jepsen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SMS Siemag AG
Original Assignee
SMS Demag AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SMS Demag AG filed Critical SMS Demag AG
Publication of AU2006284201A1 publication Critical patent/AU2006284201A1/en
Publication of AU2006284201A2 publication Critical patent/AU2006284201A2/en
Abandoned legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B37/00Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/16Control of thickness, width, diameter or other transverse dimensions
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B1/00Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B1/24Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process
    • B21B1/26Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process by hot-rolling, e.g. Steckel hot mill
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B1/00Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B1/30Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a non-continuous process
    • B21B1/32Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a non-continuous process in reversing single stand mills, e.g. with intermediate storage reels for accumulating work
    • B21B1/34Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a non-continuous process in reversing single stand mills, e.g. with intermediate storage reels for accumulating work by hot-rolling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B2265/00Forming parameters
    • B21B2265/12Rolling load or rolling pressure; roll force
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B2271/00Mill stand parameters
    • B21B2271/02Roll gap, screw-down position, draft position
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B2271/00Mill stand parameters
    • B21B2271/06Mill spring
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B31/00Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
    • B21B31/16Adjusting or positioning rolls
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B31/00Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
    • B21B31/16Adjusting or positioning rolls
    • B21B31/20Adjusting or positioning rolls by moving rolls perpendicularly to roll axis
    • B21B31/32Adjusting or positioning rolls by moving rolls perpendicularly to roll axis by liquid pressure, e.g. hydromechanical adjusting
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B37/00Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/58Roll-force control; Roll-gap control
    • B21B37/62Roll-force control; Roll-gap control by control of a hydraulic adjusting device
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B37/00Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/58Roll-force control; Roll-gap control
    • B21B37/64Mill spring or roll spring compensation systems, e.g. control of prestressed mill stands
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B38/00Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B38/00Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
    • B21B38/08Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring roll-force

Description

VERIFICATION OF TRANSLATION RE: INTERNATIONAL APPLICATION NO. PCT/EP2006/007249 I, Paul J. Collins, c/o Frank C. Farnham Company, Inc., 210 W. Front St., Suite 5, Media, PA 19063-3101, am the translator of the specification of Patent Application No. PCT/EP2006/007249, as well as the replacement pages containing amendments made during the international phase, and I state that said translation is a true translation to the best of my knowledge and belief. Translator: _ _ _ _ _ _ Dated: _ _ _ __ _ TRANSLATION (HM-812PCT-original): WO 2007/022,841 Al PCT/EP2006/007,249 METHOD FOR THICKNESS REGULATION DURING A HOT-ROLLING PROCESS The invention concerns a method for automatic gage control during rolling, especially hot rolling, with at least one rolling stand, where factors that are considered include the present mean position of the adjustment cylinders of the rolling stand and their total rolling force. DE 20 20 402 discloses a method for calculating the gage G1 of a thin, hard workpiece after a reducing pass through a reducing mill train with opposing rolling surfaces and a measuring instrument for measuring the roll separating forces, which are produced during the passage of the workpiece through the opposing rolling surfaces during a reducing operation, in which (a) a signal that is a measure of the gage G5 is generated, which is determined by the point of intersection of an appropriate mill stretch curve and an appropriate workpiece deformation curve for the reducing operation, 1 (b) a signal that is a measure of a gage G3 is generated, which is determined by the point of intersection of the measured force curve and the mill stretch curve, (c) a signal that is a measure of a range of uncertainty is generated, which is determined by the difference between signals representing the gages G5 and G3, (d) a signal that is a measure of a calculated stretch error is generated by varying the signal that represents the range of uncertainty as a function of the draft predicted for the reducing pass, of the mill stretch predicted for the reducing pass, and of the relative probability of error in predicting both draft and mill stretch, and (e) a signal that is a measure of the calculated gage G1 is generated by adding the signal that represents the gage G3 to the calculated stretch error. DE 26 57 455 Al describes a method for compensating roll deformation in rolling stands with prestressing that can be automatically controlled, in which the strip thickness is automatically controlled by hydraulic actuators, and in which the contact force (Fa), which is the sum of the rolling force and the automatically controllable prestressing force according to the following equation: 2 Fa = (Fao + (Fr - Fro)) * Ca/(Ci + Ca), is varied by hydraulic prestressing cylinders in such a way that, to the base set value (Fao) of the contact force, a supplementary set value is added, which is formed from the difference between the actual value (Fr) of the prestressing force and the initial value (Fro) of the prestressing force and is evaluated with the ratio (ca/(ci + ca)) of the spring stiffness (ca) of the outer part of the stand to the sum of the spring stiffness (ci) of the inner part of the stand and the spring stiffness (Ca) of the outer part of the stand. DE 16 02 195 Al discloses a method for calculating the gage of thin, hard workpieces, in which -- a signal that is a measure of the gage G5 is generated, which is determined by the point of intersection of an appropriate mill stretch curve and an appropriate workpiece deformation curve for the reducing operation, -- a signal that is a measure of a gage G3 is generated, which is determined by the point of intersection of the measured force curve and the mill stretch curve, -- a signal that is a measure of a range of uncertainty is generated, which is determined by the difference between signals representing the gages G5 and G3, 3 -- a signal that is a measure of a calculated stretch error is generated by varying the signal that represents the range of uncertainty as a function of the mill stretch predicted for the reducing pass and of the relative probability of error in predicting both draft and mill stretch, and -- a signal that is a measure of the calculated gage G1 is generated by adding the signal that represents the gage G3 to the calculated stretch error. Until now, the so-called gage meter principle for determining the present strip gage has been used for automatic gage control during hot strip rolling. To this end, the measured SDS, Sos of the adjustment cylinders is corrected by the calculated mill stretch g (see also Figure 1). The mill stretch g is calculated with the use of the measured rolling force FDS, Fos and a mill stretch curve I/MG. The strip gage determined in this way is then compared with the gage set value and automatically controlled. Besides the measurements of position and rolling force, an exact mill model is needed for this method. In the rolling of hard materials and thin strip, small inaccuracies in the mill model lead to relatively large errors 4 in the strip gage and sometimes instability of the automatic gage control system. Therefore, the objective of the invention is to improve a method of the type described above in such a way that the disadvantages specified above are avoided. In accordance with the invention, this objective is achieved by minimizing the mill stretch component. This is accomplished by carrying out at least one additional position measurement by detecting position signals in the immediate vicinity of the roll gap of the rolling stands. In this connection, especially the position signals between the work rolls and/or the backup rolls and/or the work roll chocks and/or the backup roll chocks are to be considered/detected. The advantage of the method of the invention is that the position measurement contains a smaller mill stretch component. Thus, only the roll flattening and the roll bending are to be considered. Other components, such as the expansion of the columns and the crossheads, do not have to be considered. Specifically in the measurement of the separation of the work roll chocks, the suspension of the Morgoil bearings, the bending of the backup rolls, and backup roll eccentricities do not have to be taken into consideration. As 5 shown in Figure 2, the prior-art method for automatic gage control is still used in its entirety and is improved or expanded by the features described above. The method of the invention results in a more exact determination of the strip gage in the case of hard materials and, especially in the case of thin strip rolling, improves the dynamic behavior of the automatic gage control system. In a further development of the invention, the signals that are obtained can also be used for automatic position control and/or for automatic swivel control and/or for calculation of the strip gage and thus for automatic control of the strip gage. A specific embodiment of the invention is described in greater detail below with reference to the accompanying schematic drawings. -- Figure 1 shows a flowchart for automatic gage control in accordance with the prior art. -- Figure 2 shows a flowchart for automatic gage control in accordance with the invention. Figure 1 shows a flowchart of prior-art automatic gage control during rolling, especially hot rolling. A rolling stand consisting, for example, of a pair of work rolls AW and 6 a pair of backup rolls SW has an operating side OS and a drive side DS. A strip B is positioned between the pair of work rolls AW. In the previously known method for automatic gage control, the cylinder position of the operating side Sos and the cylinder position of the drive side SDS are determined, and the present mean cylinder position SACT is determined. In addition, the total rolling force FACT is determined by determining the rolling force on the operating side Fos and the rolling force on the drive side FDS. The mill stretch g is calculated with the use of the total rolling force FACT and a mill stretch curve 1/MG. The present strip gage hACT is determined by measurement of the present mean cylinder position SACT and the calculated mill stretch g. The present strip gage hACT is compared with the strip gage set value hREF and used for automatic gage control. The automatic gage controller outputs the position set value for the automatic cylinder position control system. In accordance with the invention, the prior-art automatic control system is improved as shown in the flowchart in Figure 2. To this end, for example, the separation of the work roll chocks on the operating side SROS and on the drive side SRDS is measured, and then the mean separation of the work roll chocks 7 SR is determined. The value for the present mean cylinder position SAy, which continues to be determined, as in the prior art, is directly compared with the cylinder position set value SREF. The values of the rolling force on the operating side Fos and the rolling force on the drive side FDS also continue to be determined and lead to the total rolling force FACT. These are combined, in accordance with the invention, with a mill modulus MR with respect to the work roll chocks, and then the mill stretch gR with respect to the work roll chocks is determined. In accordance with the invention, the mill modulus MR depends on the selected position measurement. The position signals of the position measurement that are to be taken into consideration for the method, with at least one position signal being required, are determined between the work rolls AW and/or the backup rolls SW and/or the work roll chocks and/or the backup roll chocks. The mill stretch to be taken into consideration in the method of the invention is to be coordinated with the given site of the position signal that is obtained. 8 The separation on the operating side SROS and the separation on the drive side SRDS lead to the mean separation of the work roll chocks SR, for example. The present strip gage hACT is determined from the separation of the work roll chocks SR and the mill stretch with respect to the work roll chocks gR and is then compared with the strip gage set value hREF and automatically controlled. 9 List of Reference Symbols AW work roll SW backup roll W rolling stand B strip DS drive side OS operating side FACT total rolling force Fos rolling force on the operating side FDS rolling force on the drive side SACT present mean cylinder position Sos cylinder position on the operating side SDS cylinder position on the drive side SREF cylinder position set value hACT present strip gage hREF strip gage set value SR mean separation of the work roll chocks SRos separation on the operating side SRDS separation on the drive side gR mill stretch with respect to the work roll chocks MR mill model with respect to the work roll chocks g mill stretch MG mill modulus 10

Claims (5)

1. A method for automatic gage control during rolling, especially hot rolling, with at least one rolling stand, where factors that are considered include the present mean position of the adjustment cylinders of the rolling stand and their total rolling force, wherein at least one additional position measurement is carried out by detecting position signals in the immediate vicinity of the roll gap of the rolling stands.
2. A method in accordance with Claim 1, wherein the position signals are detected between the work rolls and/or the backup rolls and/or the work roll chocks and/or the backup roll chocks.
3. A method in accordance with Claim 1 or Claim 2, wherein the position signals are used for automatic position control.
4. A method in accordance with any of Claims 1 to 3, wherein the position signals are used for automatic swivel control.
5. A method in accordance with any of Claims 1 to 4, wherein the position signals are used for calculating the strip gage. 11
AU2006284201A 2005-08-26 2006-07-24 Method for thickness regulation during a hot-rolling process Abandoned AU2006284201A1 (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE102005040690 2005-08-26
DE102005040690.4 2005-08-26
DE102005042837.1 2005-09-09
DE102005042837A DE102005042837A1 (en) 2005-08-26 2005-09-09 Method for thickness control during hot rolling
PCT/EP2006/007249 WO2007022841A1 (en) 2005-08-26 2006-07-24 Method for thickness regulation during a hot-rolling process

Publications (2)

Publication Number Publication Date
AU2006284201A1 true AU2006284201A1 (en) 2007-03-01
AU2006284201A2 AU2006284201A2 (en) 2008-05-01

Family

ID=37198982

Family Applications (1)

Application Number Title Priority Date Filing Date
AU2006284201A Abandoned AU2006284201A1 (en) 2005-08-26 2006-07-24 Method for thickness regulation during a hot-rolling process

Country Status (12)

Country Link
US (1) US20090031777A1 (en)
EP (1) EP1919638A1 (en)
JP (1) JP2009505835A (en)
KR (1) KR20080037010A (en)
AU (1) AU2006284201A1 (en)
BR (1) BRPI0615089A2 (en)
CA (1) CA2620000A1 (en)
DE (1) DE102005042837A1 (en)
MX (1) MX2008002631A (en)
RU (1) RU2008111505A (en)
TW (1) TW200709865A (en)
WO (1) WO2007022841A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103706644B (en) * 2013-12-20 2016-04-27 秦皇岛首秦金属材料有限公司 Based on the fixed value of roller slit self-adaptation control method of calibrator detect thickness
DE102021209714A1 (en) * 2020-09-22 2022-03-24 Sms Group Gmbh Device and method for rolling metal strip

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GB1145836A (en) * 1966-09-29 1969-03-19 British Iron Steel Research Improvements in or relating to the rolling of strip
US3574280A (en) * 1968-11-12 1971-04-13 Westinghouse Electric Corp Predictive gauge control method and apparatus with adaptive plasticity determination for metal rolling mills
FR2263044A1 (en) * 1974-03-05 1975-10-03 Westinghouse Electric Corp Automatic thickness control on a four-high rolling mill - using computer to control all the process variables
US4126027A (en) * 1977-06-03 1978-11-21 Westinghouse Electric Corp. Method and apparatus for eccentricity correction in a rolling mill
US4126026A (en) * 1977-09-26 1978-11-21 General Electric Company Method and apparatus for providing improved automatic gage control setup in a rolling mill
US4909060A (en) * 1988-01-26 1990-03-20 United Engineering, Inc. Oil compression compensation system
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JPH04100625A (en) * 1990-08-20 1992-04-02 Sumitomo Metal Ind Ltd Method for automatically controlling sheet thickness
DE59505484D1 (en) * 1994-07-08 1999-05-06 Siemens Ag Device for detecting the roll gap between two work rolls of a roll stand
DE69840192D1 (en) * 1998-02-27 2008-12-18 Nippon Steel Corp FLAT ROLLING AND BLECH ROLLING
JP2000288614A (en) * 1999-04-09 2000-10-17 Toshiba Corp Gage controller for rolling mill
FR2860738B1 (en) * 2003-10-13 2006-02-03 Vai Clecim METHOD OF INCREASING THE ACCURACY OF PRODUCT TRACK CONTROL IN AN IMBRIC ROLL PLANER MACHINE AND PLANTING INSTALLATION FOR CARRYING OUT THE PROCESS
DE102004005011B4 (en) * 2004-01-30 2008-10-02 Betriebsforschungsinstitut VDEh - Institut für angewandte Forschung GmbH Control method and controller for a rolling stand

Also Published As

Publication number Publication date
CA2620000A1 (en) 2007-03-01
DE102005042837A1 (en) 2007-03-08
RU2008111505A (en) 2009-10-10
AU2006284201A2 (en) 2008-05-01
WO2007022841A1 (en) 2007-03-01
KR20080037010A (en) 2008-04-29
MX2008002631A (en) 2008-03-14
TW200709865A (en) 2007-03-16
US20090031777A1 (en) 2009-02-05
JP2009505835A (en) 2009-02-12
BRPI0615089A2 (en) 2011-05-03
EP1919638A1 (en) 2008-05-14

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DA3 Amendments made section 104

Free format text: THE NATURE OF THE AMENDMENT IS AS SHOWN IN THE STATEMENT(S) FILED 11 APR 2008

MK1 Application lapsed section 142(2)(a) - no request for examination in relevant period