Patent classifications
B21B2271/02
Bearing flotation compensation for metal rolling applications
A process inferentially determines hydrodynamic bearing flotation in a metal rolling operation for a metal roller bearing. The process receives from a mill stand processing the metal roll a rolling load of the metal roll, a gap between a pair of rollers pressing the metal roll, and a speed of the metal roll through the pair of rollers. The process further receives from the mill stand a gauge of the metal roll after the metal roll has passed through the pair of rollers. The process determines the hydrodynamic bearing flotation using the rolling load of the metal roll, the gap between a pair of rollers pressing the metal roll, the speed of the metal roll through the pair of rollers, and the gauge of the metal roll after the metal roll has passed through the pair of rollers. The process then adjusts the gap between the pair of rollers based on the determined hydrodynamic bearing flotation.
Mass flow regulation in roller devices
A method for controlling a roller line, preferably a cold roller line, which has one or more roller stands each with two working rollers, which form a roller gap, through which a roller band is transportable. One or both working rollers can shift relative to the other, so that the roller gap is adjustable. The method includes making available a reference speed, which is a parameter for controlling the roller line, measurement of speed of the roller band before the inlet into the roller gap, measurement of the thickness of the roller band before the inlet into the roller gap, and adjustment of the roller gap of one or more roller frames in the roller line on the basis of measured speed and thickness before the inlet into the roller gap as well as the reference speed.
Robust band tension control
A metal band is first rolled in a front and then in a rear (downstream) roll stand of a multi-stand rolling train. A looper between the roll stands may detect a band tension in the metal band. The band tension is supplied to a first and a second tension controller to determine an application additional target value and a speed additional target value. The second tension controller may only determine a value less than or greater than 0, as the speed additional target value, if the band tension is above or below an upper or lower band tension limit. Otherwise, the speed additional target value may be 0. The first tension controller is also supplied with a target tension that falls between the band tension limits. The application additional target value may be used to act on the rear roll stand.
Method for producing hot-rolled seamless pipes having thickened ends
A method for producing hot-rolled, seamless pipes having at least one wall thickening which can be arranged at any positions over the length of the pipe, wherein by means of a multiple-stand mandrel bar rolling mill, the rolls roll a hollow shell on a mandrel bar as an inner tool to a required nominal wall thickness and produce at specified positions over the length of the pipe a required wall thickening on the outer side of the pipe by opening the rolls in the rolling stands. The thickened wall is produced and finish-rolled by two rolling stands that are consecutive as seen in the rolling direction, in which the deviations of the finished contour of the thickening from an ideal circular cross-section are minimised, wherein the rolling stands located upstream are likewise opened as to avoid any contact of the rolls of these rolling stands with the previously produced thickening.
Rolling method for boards with different longitudinal thicknesses
Disclosed is a rolling method for a board having various longitudinal thicknesses, comprising the following steps: 1) setting a number N of uniform-thickness segments of a sample, thicknesses h.sub.1, h.sub.2, . . . , h.sub.N of the uniform-thickness segments, lengths L.sub.1, L.sub.2, . . . , L.sub.N of the uniform-thickness segments, and lengths T.sub.1, T.sub.2, . . . , T.sub.N1 of transitional segments between the uniform-thickness segments, the N uniform-thickness segments having N1 transitional segments therebetween, and both the thickness and length having a unit of mm; 2) selecting a raw material; 3) setting a rolling force, a roll gap and a rolling period of time for each segment; 4) preparing rolling; 5) conducting rolling; 6) optimizing rolling parameters, measuring thicknesses and lengths of the uniform-thickness segments and lengths of the transitional segments after the rolling member is rolled; comparing the measured thicknesses of the uniform-thickness segments with the set thicknesses for the sample, so as to correct the rolling force P.sub.i and roll gap G.sub.i set for each segment in step 3); comparing the measured lengths with the positions marked in step 4), so as to correct the rolling period of time set for each segment in step 3); repeating steps 4) and 5) using raw materials of the same size, and making correction again, wherein a rolled member meeting the requirements of the sample can be made after 2-3 times of trial rolling. This method avoids preparation of a raw material in the form of a roll, avoids study on a complex controlling method for various-thickness rolling of the roll, and saves the raw material and test time.
Rolling mill for solid elongated products
A rolling mill for solid elongated products, defining a rolling axis, including first and second rolling stations. Each station includes a load-bearing structure, a removable roll-holder cartridge with three rolling rolls movable radially and rotating around spaced rotational axes, and a roll having a vertical rotational axis. A system synchronizes mechanical adjustment of the rolls. Three actuators mount on the load-bearing structure; three gear motor groups connect to the rolls by single extensions. The second station rolls are rotated 60? from the first stations. The rolls with a vertical axis of the first and second stations are arranged on opposite sides of the rolling axis. All rolling stations allow lateral extraction of roll-holder cartridges from the same side of the rolling mill. The stations on the extraction side have actuators movable relative to the load-bearing structure. The stations with vertical rolls arranged on the opposite side have fixed actuators.
Method for Cold Deformation of an Austenitic Steel
A method for partial hardening of an austenitic steel by utilizing during cold deformation the TWIP (Twinning Induced Plasticity), TWIP/TRIP or TRIP (Transformation Induced Plasticity) hardening effect. Cold deformation is carried out by cold rolling at least one surface of the steel with forming degree () of 560% in order to achieve in the steel at least two consecutive areas with different mechanical values in thickness, yield strength (R.sub.p0.2), tensile strength (Rm) and elongation, having a ratio (r) between the ultimate load ratio (F) and the thickness ratio (t) of 1.0>r>2.0, and in which the areas are mechanically connected to each other by a transition area having a thickness that is variable from the thickness of the first area in the deformation direction to the thickness of the second area in the deformation direction.
Method of controlling a roll gap in a rolling mill
A method of controlling a roll gap between first and second work rolls (102, 104) that includes defining a plurality of work surface locations spaced apart along the first work roll (102) in the longitudinal direction; obtaining a radius of the work surface (102a) of the first work roll (102) at each of the work surface locations; based on the radii of the work surface locations, obtaining a longitudinal profile of the work surface (102a); based on the longitudinal profile, tilting the first work roll (102) relative to the second work roll (104) in the common plane in order to reduce a difference in the average size of the gap either side of a centerline (CL), which bisects the longitudinal axes of the first and second work rolls (102, 104).
ROBUST BAND TENSION CONTROL
A metal band (1) is first rolled in a front (upstream) and then in a rear (downstream) roll stand (2a, 2b) of a multi-stand rolling train. A looper (3) applied on the metal band (1) between the roll stands (2a, 2b) detects a band tension (Z) present in the metal band (1). The band tension (Z) is supplied to a first and a second tension controller (8, 9), which determine an application additional target value (s*, F*) and a speed additional target value (v*). The second tension controller (9) only determines a value less than or greater than 0, as the speed additional target value (v*), if the band tension (Z) is above or below an upper or lower band tension limit (Z1, Z2). Otherwise, same returns the speed additional target value (v*) to the value 0. The first tension controller (8) is also supplied with a target tension (Z*) that falls between the band tension limits (Z1, Z2). The first tension controller (8) determines the application additional target value (s*, F*) using a determining standard based on the deviation of the band tension (Z) from the target tension (Z*). The determining standard also permits a value different to 0 as the application additional target value (s*, F*) if the band tension (Z) falls between the band tension limits (Z1, Z2). The application additional target value (s*, F*) acts on the rear roll stand (2b). The speed additional target value (v*) acts on the front roll stand (2a) with a positive indicator, or on the rear roll stand (2b) with a negative indicator.
ROLL STEERING CONTROL SYSTEMS AND METHODS FOR TANDEM MILLS
Systems and associated methods for controlling roll steering during rolling of a metal substrate may include a steering control actuator adapted to control an inclination of a work roll of a work stand of the rolling mill, a sensor configured to measure a parameter of a metal substrate upstream from the work stand, and a controller operably connected with the steering control actuator and the sensor. The controller may generate a model for the work stand and determine an adjustment value for the work stand, receive the measured parameter from the sensor, and determine an expected output parameter by adjusting the measured parameter by the adjustment value. The controller may also compare the expected output parameter with a target output parameter and actuate the steering control actuator such that the expected output parameter is within a predefined tolerance of the target parameter.