Three-roll mill longitudinal rolling
(57) Abstract:The invention relates to rolling production and can be used in the reduction and sizing mills for the manufacture of pipes, as well as in mills for continuous rolling of rods and wire. The inventive three-roller mill includes a housing 1, the bores of which the bearing supports 2 posted by drive shaft 3 with the working roller 4 and bevel gears 5 and 6, and inclined thereto at equal angles two shafts 7 and 8 with the working rolls 4, having at least one bevel gear 9, 10. Bevel gears 5, 6, 9, and 10 were made with a circular shape of a tooth, the direction of the generatrix line of which coincides with the direction of rotation of the corresponding shaft. The invention allows to increase the load capacity of the gears, to provide a more smooth and transmit a higher torque. 4 Il. The invention relates to rolling production, and more precisely to the three-roll mill longitudinal rolling, and can be used when designing the pressure reducing and sizing mill for pipes and mills for continuous rolling of rods and wire.Known three-roll reducing mill (1), with aetsa by transferring torque from one drive roll is a bevel gear, located console on the supporting shafts of the other two rolls.A disadvantage of the known design of the cage is a low load capacity and durability due to low load capacity conical toothed gearings and bearings for rolls, placed in a confined space housing three-roll stands, and also due to the uneven distribution of radial and axial loads on the bearings of the rolls arising in the toothed gearings.From the known three-roll mill longitudinal rolling closest in technical essence is a three-roller working crate reducing mill (2), comprising a housing, the bores through which bearing is placed a shaft with a working roller and tapered gears, and inclined thereto at equal angles two shafts with work rolls having one bevel gear.A disadvantage of the known constructions of three-roller working stand reduction mill is a low load capacity and durability due to the low load capacity of the gears and bearings for work rolls, placed in a limited space of the shell made of a support shaft, emerging in the toothed gearings.The objective of the invention is to increase the load capacity of the gear bevel gearing and ensuring the transmission of higher torques.The proposed design run three-roll stands longitudinal rolling provides increase its load capacity and durability due to the fact that the circular shape of the tooth bevel gears provide smoother operation of the gearing and transmits higher torque, since the contact area in this case is increased, and the coincidence of the direction of their generatrix line with the direction of rotation of the corresponding shaft enables you to evenly distribute radial and axial loads on the bearings, resulting in toothed gearing in the transmission of torque.In Fig. 1 shows a kinematic diagram of the three-roll stands longitudinal rolling; Fig. 2 - the option of arranging the gears and bearing three-roll stands longitudinal rolling; Fig. 3 - scheme of radial and axial forces engaged the coincidence with the direction of the generatrix line of the inclination of the tooth with the direction of rotation of the shaft; Fig. 4 is a diagram of the radial INIA shaft.Three-roll mill longitudinal rolling consists of a casing 1, are placed in the bores through the bearing 2 shaft 3 with the working roller 4 and bevel gears 5 and 6, and inclined at equal angles to the shaft 3 of the two shafts 7 and 8 with the working rolls 4, each of which has a corresponding bevel gear 9, 10. Bevel gears 5, 6, 9, and 10 were made with the circular gear, the direction of the generatrix line of which coincides with the direction of rotation of the corresponding shaft (Fig. 1 and 2).The device operates as follows.Torque from the drive shaft 3 by means of bevel gears 5, 6, 9, 10 is transmitted to the shafts 7 and 8. In calibre, formed by the rollers 4, set the workpiece and is crimped to the desired diameter. This circular form of tooth bevel gears provide smooth quiet operation of the gearing and makes it possible to transmit higher torque, since the engagement with the circular shape of the tooth contact patch is larger and higher Flexural endurance compared to the mesh, where the form of the tooth straight.Efforts in the links as follows. If the angle of inclination of the generatrix line of the tooth coincides with napravlenieah P and axis Q of the effort is in engagement with forming a separating cone angle , more 90about( > 90about). The vectors FWand Ftolie on one line and their absolute values are equal (Fto)=(FW), as the force of action is equal to the reaction force from the conditions of equilibrium, with > 90aboutas force FWin the calculated cross section perpendicular to a generating line of the tooth. If the angle of inclination of the generatrix line of the tooth does not coincide with the direction of rotation of the shaft (Fig. 4) < 90about.For gearing, where the form of the straight tooth, = 90about. When = 90aboutradial components of PWand Ptoand axial components of QWand Qtofrom the efforts of the Ftoand FWrespectively, i.e., PW=Ptoand QW=QK.< / BR>With increasing angle , i.e., > 90about(Fig. 3) PW<Pand QW>Qtoaccordingly when the < 90about(Fig. 4) PW>Ptoand QW<Q. Due to the fact that on the shaft 3 mounted two gears 5 and 6, the radial load on the bearing support efforts in engagement will double PW=2PW. The axial load on the bearings of the shaft 3 is in this case equal to 0, since the axial forces on the gears 5 and 6 are directed in opposite directions and will mutually of Compline tooth coincides with the direction of rotation of the shafts, as for the bearing support of the shaft 3 acts total radial load forces PWsmaller absolute value of the radial load Ptoacting on the bearings of the shafts 7 and 8. In this regard, the bearing support shaft 3, 7 and 8 are more evenly loaded radial forces from the operation of the gearing compared to the condition when the direction of the generatrix line of the tooth does not coincide with the direction of rotation of the shafts (Fig. 4) and a bearing support shaft 3 acts radial force resulting from the sum of large forces PW(PWwhen <90 o>Pto).At > 90aboutlarge in absolute value the efforts of QWmutually compensated, and a bearing support shafts 7 and 8 are powers of Qtomuch smaller in absolute value than QW. When <90 oobviously the opposite: the smaller force QWmutually compensated, and on the bearings of the shafts 7, 8 are large axial load Qto. Therefore, when the coincidence of the generatrix line of the inclination of the tooth with the direction of rotation Valov their bearings will be more evenly loaded, which increases their load capacity and durability to stand the loading capacity and ensures transmission of higher torques. Three-roll MILL LONGITUDINAL ROLLING, comprising a housing, the bores through which bearing is placed a shaft with a working roller and tapered gears and inclined thereto at equal angles two shafts with work rolls having one bevel gear, wherein the bevel gear is made with a circular shape of a tooth, the direction of the generatrix line of which coincides with the direction of rotation of the corresponding shaft.
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