The caliber of the roll tube mill
(57) Abstract:The use of the invention relates to the caliber of the grooved roll tube mill, mostly round shape for reducing rolling mill with a three-roll mill, in particular for rolling thin-walled tubes with the relationship of wall thickness to diameter of more than 0.25. The inventive circuit caliber of each roll is in the area of the bottom of the gauge widening in diameter, which can be deformed area of the material, laminated in the ledge roll appropriate, previous in the direction of rolling, caliber. The invention can improve the contour of the caliber that prevents or makes it more flat unwanted sharpening on a contact surface between the rolled product and roller. 2 C.p. f-crystals, 2 Il. The invention relates to the caliber of the grooved roll, mostly round shape for reducing rolling mill with a three-roll mill, in particular for rolling thin-walled pipes with the ratio of wall thickness to diameter of more than 0.25.In the pressure reducing pipe rolling mill according to the prior art for walled pipes usually are not round, and EA. Long axis lies along the line of recoil rolls and is longer than the short axis of the previous caliber. Due to this, try to avoid output of rolled material in the rolling gap and printing rolling gap. Such forms caliber limited, however, by rolling technology, if rolled pipe with respect to the thicknesses higher than 0.1. That's when the so-called polygonization, i.e. the deviation of the inner contour of the pipe from the desired round shape. In the extreme case, this polygonization can lead to approximately hexagonal cross-section, which greatly limits the application of the pipe.If you want to laminate thin-walled pipe, it can hardly be done using the well-known oval calibration, in this case, you must use the calibration, which is close to a round shape. Using these calibrations, polygonization suppressed stronger; the relationship to that described in the journal "Archiv fuer das Eisenhuettenwesen", year 41, No. 11, November 1970, pages 1047 - 1053. The result, according to this prior art are invited to apply for pipe lines with a thin range of pipes, special calibration is atki, that is mainly round the calibration. This is possible because the thin-walled pipes are much less prone to the formation of the imprint of the rolling gap on the outer surface than the thin-walled tube. The choice of caliber holes should be carried out in such a way that the difference between the longest and shortest length of the contact surfaces is minimal, so the contact surface of the roller/tube of rectangular form.When applying the ideas according to the above publication, it was found that in the ranks of calibers with a small hole gauge between the pipe and the roller is not achieved uniform contact. Using conventional processing techniques calibers get the contact surface with 3 vertices, namely in the bottom of the gauge and the protrusions caliber. This is shown on page 1052, Fig. 11 the specified publication. Peaks at the contact surface between the roller and the rolled product produce pipes with a very thin wall with the ratio of wall thickness to diameter of more than 0.25 and again to the roundness of the pipe, and obviously affect the quality. Additionally, increased friction, which leads to more severe wear of the rolls.For solving the problem, according to the invention, it is proposed that the contour of each roll had in the area of the bottom of the gauge widening in diameter, which can be deformed area of material laminated to the tops of the roll corresponding to the previous in the direction of rolling, caliber.Targeted expansion of the diameter of the caliber in the area of the bottom of the gauge it is possible to reduce the contact length in the bottom of the gauge in such a way that results in an even contact surface. Thanks to this pipe in the area of the bottom of the gauge is no longer subjected to excessive stresses, as is clearly visible in the prior art tops flattened.Particularly favorable, if the extension in diameter from the diameter of the gauge is approximately 0,5-1% of the diameter of the caliber and occurs on both sides of the middle of the bottom of the gauge ring angle equal to approximately 10 - 15o. When these dimensions are obtained good results in the pipe, i.e. the contact surface between the rolls is m invention provides for expanding the diameter in the area of the protrusion gauge, in addition to expanding the diameter in the bottom of the gauge. This extension diameter can be achieved, for example, an increase of 3-5 mm radius transition at the edge of the swath. It was found that with these radii, which in the prior art are less than 3 mm, also achieved a significant improvement deformation ratios in the caliber and contact of taper can be significantly reduced and in the marginal zone of the caliber roll.In Fig. 1 shows a front view in partial section of a caliber roll, according to the invention, the incoming pipe; Fig. 2 - the projection on the horizontal contact area between the pipe and the caliber of the roller according to the invention.In Fig.1 position 1 indicated one of the three roll calibers, forming the entire caliber, according to the invention, rotating around the axis 2. Rolled pipe is shown schematically position 3. Mainly, round caliber 4 roll 1 is in the area of the bottom of the caliber of the extension 5 in diameter, that is, the recess in the bottom of the gauge. Other extensions under the digit 6 in diameter is provided in the area of top caliber, namely in the form of increased diameter at the edge of the roll caliber. In Fig.1 for a better understanding of the dashed line 7 shows the typical shape of the caliber. This normal form In the drawing shows the contact top 8 in the area of the bottom 9 of the caliber 1 roll and in the area of the protrusion 10 gauge on both edges of the roll 2. These peaks 8 and 10 are formed on the inlet side of the roll 1 and result in the described internal roundness of the finished pipe 3.If we consider the contact surface of the pipe on the roll according to the invention, carried out by the solid line in Fig. 2, we can see that the vertices 8 and 10 are greatly reduced, due to what turns out almost rectangular contact surface with a contact length of 10. These changes to the contact surface caused by the extensions 5 and 6 of a diameter in the bottom of the gauge and in the area of the top caliber. 1. The caliber of the roll, mostly round shape for reducing rolling mill with a three-roll mill, in particular for rolling thin-walled pipes with the ratio of wall thickness to diameter of more than 0.25, characterized in that the caliber of each roll (1) has a contour in the area of the bottom of the caliber of the expansion (5) in diameter, which can be deformed area of the material, laminated in the vertices of the corresponding roll, previous in the direction of rolling, caliber.2. Caliber under item 1, characterized in that the extension (5) the diameter is, if we assume the diameter of the caliber, about 0.5 - 1.0 of the diameter of the caliber and is located on both sides from the center of the bottom of the gauge with angle environment is about the diameter of the bottom (9) has the expansion (6) in diameter in the area of the top caliber.
FIELD: automation of rolled stock production.
SUBSTANCE: at controlling thickness of tube wall in multi-stand continuous stretch-reducing mill, thickness of tube wall is measured behind mill by means of wall thickness measuring devices. Measured values are processed in computing unit. Revolution numbers of drive engines of rolls are controlled by means of units for controlling revolution number. In order to minimize formation of inner multi-arc profile at passing tube, total elongation value is kept constant due to changing revolution number of drive engines of rolls under control of computing unit.
EFFECT: enhanced quality of products.
5 cl, 4 dwg
FIELD: manufacture of sheathing determined shape by cold reduction of hollow welded blank such as tube.
SUBSTANCE: method comprises steps of feeding and placing blank onto feed roller table; orienting and matching blank relative to rolling mill; deforming hollow welded blank between rolls of several successively arranged stands at simultaneously reducing blank along its perimeter and creating longitudinal tension drawing effort; finally working blank in multi-roll pass according to size of ready of product. Hollow welded blank is deformed while perimeter and thickness of its wall are hold constant during the whole manufacturing cycle beginning from guiding welded blank till discharge of ready product for several successive transitions. Strict order of said transitions is determined by creation of deformation zones at optimized stress-deformed state of metal and by deformation intensity between stands of rolling mill. Accuracy for keeping constant values of wall thickness and perimeter of initial welded tubular blank is controlled due to calibration of rolls in such a way that to act locally upon metal flowing in tube in critical points along perimeter. Reduction is realized due to preliminarily reducing tube along its contour for shaping ribs; further reducing blank for forming two basic surfaces of the most simple geometry and preliminarily forming two remaining basic complex-geometry surfaces. Then said two remained basic complex-geometry surfaces are finally reduced. Triangle bending portion is rolled and grooves are formed in vertical end strut and supporting platform. Triangle bending portion is additionally rolled and geometry parameters of shape that are important for operation are finally sized with possibility of compensation of errors of shape members with free dimensions. Then ready shape is straightened. Reduction is performed at similar angular velocity of rolls in all stands and slip is provided in zones of velocity error. Procedures of preliminary reduction of tube along its contour for forming ribs, further reduction of blank for forming two basic simple-geometry surfaces, preliminary forming of two remaining basic complex-geometry surfaces, further reduction for finally forming two complex-geometry basic surfaces, rolling triangle bending portion and forming grooves in vertical end strut and in supporting platform are performed in double-roll stands. Additional rolling of triangle bending portion, final calibration and straightening of ready shape are performed in multi-roll stands. Welded tubular blank is oriented in feed roller table in such a way that welded seam is in lower flange of shape that is parallel to supporting platform. The whole manufacturing process is realized in the same line. Invention provides possibility for acting upon stress-deformed state of metal in deformation zone for producing sheathing preset-contour shape from widely used in industry welded tube blank with diameter 114 mm and wall thickness 3 mm during optimized technological mode concerning metal state and deformation intensity.
EFFECT: enhanced accuracy of geometry size, lowered energy consumption for making shape.
5 cl, 5 dwg, 1 ex
FIELD: technological sizing tool for reduction tube rolling mill.
SUBSTANCE: sizing tool includes several successively arranged two-roll reducing shaping roll grooved passes and multi-roll passes for final sizing and straightening of ready product. Said shaping roll grooved passes are arranged according to strict order without angular shift of their parting planes. Profile of cross section of shaping rolls of each next pass is formed by recesses and protrusions with curvilinear and (or) rectilinear surfaces with possibility of proportional geometrical approach to shape of ready product. It is achieved due to satisfying condition of equal values of summed perimeter of grooved rolls of each stand and outer perimeter of initial blank. Profile of finish roll grooved passes is identical to outer contour of ready product and it is possible to adjust it in admissible range while using sixteen reduction shaping stands and four finish passes. According to invention it is possible to act upon stress- deformed state of metal in deformation zone for making preset-contour section of widely used in industry welded tube 114 x 3 mm in manufacturing mode optimal from view point of metal state, deformation intensity and comfortable condition of tool operation.
EFFECT: simplified design and manufacturing process of rolls, improved accuracy of products, lowered energy consumption.
2 cl, 5 dwg
FIELD: rolled tube production, namely manufacture of sheathing determined-contour section by cold reducing of hollow welded blank.
SUBSTANCE: reducing mill for cold reduction of sheathing determined section of hollow welded blank such as tube includes accumulator, inlet roller table, housing supporting successively arranged stands, technological sizing tool. Knocking out roller table, drive unit of mill and control panel. Technological sizing tool includes row of two-roll shaping roll grooved passes mounted in housing without shift of their parting planes and arranged one after another. It allows form by initial reduction in first stands shaping ribs of section; by further reducing simple-geometry basic surfaces, basic surfaces with more complex shape, rolling triangular bent portions and forming grooves on vertical end strut and on supporting site. Parting planes of all two-roll passes are arranged in the same plane. Summed (for two rolls of each stand) perimeter of cross sections of roll passes while taking into account protrusions, recesses with rectilinear and (or) curvilinear surfaces is equal to perimeter of initial hollow welded blank. Mill also includes sets of non-driven rollers whose rotation axes are normal to rotation axes of rolls. Said non-driven rollers are mounted between first shaping stands. Multi-roll roll grooved passes are used for finally sizing and straightening ready product with possibility of compensating admissible fluctuations of hollow welded blank. Drive unit is in the form of separate kinematic circuits with individual sources of torque for providing constant revolution number of rolls in all stands. Diameter of roll grooved passes are calculated according to condition of constant drawing speed of section through all stands and similar cross section areas of each intermediate section and initial blank. Invention provides possibility for acting upon stress-deformed state of metal in deformation zone for producing sheathing preset-contour section of widely used in industry welded tube 114 x 3 mm in manufacturing mode optimal from view point of metal state, deformation intensity and comfortable condition of tool operation.
EFFECT: simplified design and adjustment of mill, enhanced accuracy of products, lowered energy consumption.
FIELD: tube production, namely operation method of stretch-reducing mill for rolling finite-length tubes.
SUBSTANCE: rolling mill includes at least two rolling stands arranged one after another along tube feed direction. Each rolling stand includes at least two mutually engaged rolls. Each roll rolls tube along predetermined peripheral zone of tube. Rolls of two different stands are driven by means at least of two drive units for enhancing quality of successive processes. Method comprises steps of determining time moment when rear end (along feed direction) of tube leaves last outlet rolling stand; setting time interval of predetermined duration including time moment when rear end of tube leaves outlet rolling stand; controlling drive unit of outlet rolling stand in such a way that to lower at said time interval revolution number of rolls of outlet rolling stand and to provide tube discharging at stable speed. Invention provides uniform motion of tube for achieving desired accuracy of process.
EFFECT: elimination of acceleration of tube at outlet of last rolling stand.
11 cl, 5 dwg
FIELD: three-roll rolling stand, possibly finish stands of sizing and reducing mills where roll load is slightly less than in rough rolling stands, calibrating mills.
SUBSTANCE: three-roll working stand for lengthwise rolling with adjustable roll gap and with one inlet shaft includes housing where three roll units mutually joined through cone gear wheels not changing their position during roll gap adjustment are mounted. Simultaneous adjustment of all rolls is realized due to rotation of eccentric sleeves by means of their rotation drive mechanism. Each cone gear wheel is mounted in housing of stand in rolling bearing assemblies. Drive shafts of rolls are hollow ones and they are provided with internal teeth.
EFFECT: improved operational efficiency of stand, simplified adjustment of roll gap.
2 cl, 4 dwg
FIELD: technological processes.
SUBSTANCE: invention may be used for production of encasing steel profiles from welded tubular billets by method of cold sink drawing-down. Mill contains accumulator, supply roller bed, plate with cages installed in it one after another, roller bed-kicker, mill drive and control panel. Every cage is equipped with stands that are connected by means of ties and fixed at rolling mill plate. Every stand is equipped with vertical rectangular groove on front surface and T-shaped grooves at side ends. Mill is equipped with additional hinged vertical cages with molding rollers, one of which has the possibility of centre-to-centre distance regulation between them. Hinged cages are installed with the possibility of position regulation in respect to profiling axis in vertical and horizontal directions.
EFFECT: simplification of design and mill adjustment; expansion of mill technological resources at the account of additional elements application; higher article accuracy and reduction of power inputs.
2 cl, 5 dwg
FIELD: technological processes.
SUBSTANCE: invention may be used for production of encasing steel profiles from welded tubular billets by method of cold sink drawing-down. Method includes deformation of hollow billet in rollers of cages and creation of longitudinal pulling force at identical speeds of rollers' rotation in all cages until profile with required dimensions is obtained. Deforming is carried out by anti-crossbreaks with preservation of perimeter without account of billet thickness and further calibration of profile. Formation of sections that are hard-to-reach for technological tool is performed by their exposure to neighbouring active parts, which are subjected to rollers effect. Angles of bent end during deformation of profile elements are selected based on condition of equality of ratio of bent end angles values for smoothly deformed sections and for intensively deformed sections 3-5. Directions of deformations are selected so that centres of masses of sequentially produced profile during billet displacement from cage to cage are located along single straight line that matches rolled metal axis.
EFFECT: invention allows to expand technological resources of rolling mill; to increase quality of articles; to simplify design and reduce mill material intensity and power inputs.
2 cl, 4 dwg
SUBSTANCE: technological calibration tool includes series of several forming pinch passes and final calibration and trimming passes for finished product. Roll passes for final calibration are compound to enable relative rotation of working roll surfaces forming profile areas and removed from roll rotation axis at different distance. Just one element out of roll components is guiding, and guided elements of compound rolls feature bearings.
EFFECT: reduced power consumption of mill; improved article quality and precision and enhanced life time of tool.
2 cl, 1 dwg
SUBSTANCE: it is implemented delivery of blank to supply roller bed and its straining at several stages in rollers of several placed stands with keeping of perimetre and thickness of wall. Preliminarily it is cogged blank by contour for receiving of ribs, following reduction there are received two locating reference points in multirolled stands, it is finished by following reduction forming of two rest locating reference points of irregular shape. It is implemented rolling of flap of triangular shape and there are received grooving on vertical butt post and joggle. It is implemented final rolling of flap of triangular shape and final calibration of geometrics in stands with different angular velocity of calibrating elements of rollers with usage of rolling friction on effective area of rollers elements in places of maximal disparity of its angular velocities.
EFFECT: it is reduced rollers wear, increased its durability, and also increases accuracy of manufacturing of contour form profile from hollow welded blank of round shape.
4 cl, 5 dwg, 1 ex