ES2243904T3 - PROCEDURE AND PLANT OF LAMINATION FOR THE OBTAINING OF WIRE, BARS OR TUBES WITHOUT SEWING. - Google Patents

Abstract

The invention relates to a method for producing rods, bar stock or seamless tubes on a rolling stand for rolling hot metal material. Said rolling stand optionally comprises, when seen in the direction of rolling, a piercing-crossrolling mill, a multiple-stand stretch-rolling mill as the main stretching stage (4), a drawing mill (6), a finishing mill (10) and a rod rolling block (15) and devices, mounted upstream, intermediately or downstream thereof, such as a preheating furnace and a reheating furnace (11), roller tables (14) and a cooling bed (13). According to the inventive method, in the main stretching stage (4), a three-roller continuous rolling mill (3) is used both for rolling tubes and for massive rolling for producing bar stock, rods or the like. For massive rolling, the mandrel bar used for tube milling is brought out of the operative position and the provided bar stock rolls calibrated for a larger diameter reduction than used for tube milling are replaced by rolls calibrated for tube milling. A rolling mill suitable for carrying out the inventive method has, in the main stretching stage (4), a multi-stand three-roller continuous rolling mill (3) adapted to receive bar stock rolls or tube rolls and a device for removing the mandrel bar.

Description

Procedure and rolling plant for Obtain seamless wire, bars or tubes.

The invention relates to a method and a rolling mill for obtaining wire, bars or tubes seamless in a rolling mill for gender rolling heated metal, in view of the sense of lamination optionally a drill train, a rolling mill Polystructural as the main stretching stage, a plant extractor lamination, a finishing rolling mill and a block wire laminator as well as arranged devices formerly, intermediate and posterior, such as an oven heater arranged previously and subsequently, paths of roller, separating devices and a cooling bed.

To enable better performance of the rolling mill and not to need pipes another lamination plant different from the one for obtaining wire, bars or the like generated from rolling, it has known, from DE 199 35 647 A1, how to carry out lamination of wire, bars or the like, as well as the lamination of tubes without sewing, in the same rolling plant in two lines of lamination, using a part of the aggregates of the plant well in the lamination of tubes (seamless tubes) as well as in the massive lamination (wire, bars or the like). Although it is reduced with it the number of aggregates needed in total, since it they can use, for example, furnaces, separation devices, the cooling bed and parts of existing roller paths in the rolling mill universally, they are necessary, immediately behind the oven that heats the laminate up to the lamination temperature, a positioned device subsequently for transverse transport and, side by side, a lamination line for wire or bars and one for pipes, is that is, parallel to each other next to two other rolling lines separately. They are grouped in the material flow or well in the direction of lamination just too far ahead of A common lamination line.

The object of the invention consists, by consequently, in creating a rolling process and a plant of lamination of the initially mentioned type, which allow a optimal performance with additional material expenditure reduced.

This task is solved with a process according to the invention by the fact that a "konti" 3-cylinder lamination plant is used in a main stretching stage and is used both for the lamination of tubes and also for the massive lamination in the Obtaining bars, wire or the like, carrying a godmother rod used for tube rolling, and exchanging bar rolling cylinders prepared with calibrated cylinders for a large diameter reduction against the cylinders with their calibrated cylinders for tube rolling. An expert understands by " konti laminating plant", sometimes also called " konti tube laminating plant", a laminating plant that consists of several structures one behind the other with an inner madrinadora bar, as it has been known, for example, by the DE-Z "Berg- und Hüttenmnnische Monatshefte 130 (1985) notebook 7, pages 205 to 211."

While in the known rolling mill is positioned the massive line separated from the lamination line of tubes, a single line can be used according to the invention for both purposes, so it is not just the investment costs essentially lower, but also the costs of maintenance. This forms the basis of exploitation consistent with 3-cylinder technology, as it has been recognized that a universal lamination is possible, despite the requirements contradictory - in the rolling of tubes it is usually changed little outside diameter to avoid technical inconvenience of procedure and the high stretch is formed by the central hole, while massive lamination has to guarantee a great diameter reduction, to achieve the necessary stretching -. Is also for that reason compared to perforated support laminators Traditional with 2-cylinder structures in the core area of materials tensile stresses cannot appear, but pressure tensions, which reduces the danger of the formation of internal defects considerably. The stress behavior in the lamination genre during lamination in laminators of 2 or 3 cylinder support is fully described by "Herstellung von Rohren", Verlag Stahleisen 1975, page 28 up to 31.

In the transition from one type of lamination to the other type of lamination according to the invention are provided, for lamination of tubes and massive lamination, different cylinders, in which the cross section is different because of the adapted calibration and different, whose external form is, however, the same, so that a simple exchange can be made. The specific number of the 3-cylinder arrangement or structures in the main stage goes in function of the desired degree of stretching, deflecting the decrease per step, or the reduction of the decrease in the number of bars in the lamination of tubes. The right measures are known in this case and pending for the used or hollow block and the respective material properties.

An advantageous procedure configuration according to the invention provides that it is also used for the train perforator previously arranged in the main stage of stretching, a 3-cylinder inclined rolling mill, whose cylinders perforated are exchanged for mass lamination with a bar decking godmother against steel bar cylinders, prepared with cylinders calibrated for a reduction of the diameter. He 3-cylinder inclined rolling mill in a drilling mill according to the invention then enables in the case of a deviated bar of godmother, massive lamination and obtaining different steel bar diameters in the sense of a previous reduction, that is, of a reduction of the aliquot cross section referred to the total reduction of all laminators. He too inclined perforator laminator fulfills this its function universal.

A rolling mill shows, for the realization of the method according to the invention in the step main stretch, a 3-cylinder rolling mill "konti" Polystructural and formed for the housing of rod cylinders Steel or tube cylinders and a device for disposal of perforated dome bar. The "konti" laminator or the main stretch stage welcomes in a good or other framework structures or sets of cylinders, consisting respectively in three cylinders. For the exchange can be prepared next to the laminator "konti" corresponding structures, which can get into operating position after removing previous frame structures. Alternatively, a cassette construction or also just changing the cylinders in the frameworks of structures, which remain in the frame. The bar godmother can be placed in an out of order position in the change of laminator "konti" of three cylinders to lamination massive in the simplest case, by means of the clamping device for the godmother bar. This also applies to the dome bar perforated inclined rolling mill previously arranged optional to the main stretch stage in the case of tube rolling, which is formed according to a configuration of the invention, as well as a usable 3-cylinder inclined rolling mill universally

A preferred configuration of the invention provides that it is assigned to the "konti" 3-cylinder laminator the main stretch stage, a number regulation of Revolutions In this case they can be advantageously carried out. different rolling speeds in tube rolling and bars.

If the extractor laminator positioned behind the main extender advantageously shows two units of structures positioned at a distance from each other with a scissor introducible ends provided between them, can be cut from Simple way in massive lamination before laminating additionally defective ends. In the rolling of tubes you can dispense, on the contrary, with the use of scissors.

After the extractor laminator follow advantageously an additional heating oven. From there then the heat treated steel bars arrive or, for for example, steel tubes alloyed or not alloyed to the rolling mill finish. This can comprise a custom laminator, a laminator reducer or a stretch reduction laminator.

If you have to roll a steel bar to produce a wire, is positioned according to the invention behind the cooling bed a roller path, which leads to a block of wire.

Other details of the invention result from the explanation and drawing, which shows in a unique figure in a a laminator according to the invention in a very schematic way horizontal.

The universal rolling mill represented in the scheme of the plant works in a line, that is, in deviation from the representation of the drawing connects the part of the plant shown in the lower half of the figure linearly, to the parts of the plant in the upper half of the drawing, which is indicated by the winding line, a pre-fed metal (block used used) well to give seamless tubes or bars, wire or Similar mass lamination genre.

The figure shows an oven 1 with a feeding device 2 for the previous laminating material, for example blocks, for example of bar casting material. In the oven the blocks are heated to a temperature of lamination. In the execution example, a block is sent there heated employee, to a slanted and shaped inclined rolling mill as a 3-cylinder inclined laminator 3, guiding the block in a feeding groove and deforming the block by rolling over a dome bar provided with a mandrel to give a hollow block as preparation for the next lamination to give a tube without sewing. One such inclined laminator 3 is known in construction of 3 cylinders to obtain tubes. If you don't have to laminate tubes, but bars or wire, takes place in the inclined laminator 3-cylinder with a removed mandrel drill bar, a massive block reduction and compression of the structure.

From the 3-cylinder inclined laminator it takes feed the hollow blocks or solid blocks to subsequent laminating devices. This includes a main stretch stage 4, which is configured in this case as a laminator "konti" of 3 cylinders 5 of 6 structures. Other numbers of structures are also possible. This is followed by extractor laminator 6, which shows in this case two units structural 6a, 6b positioned at a distance from each other. Both between the 3-cylinder "konti" laminator 5 of various structures and the extractor laminator 6 as well as between both units Structural 6a, 6b of the extractor laminator 6 are provided scissors for the introducible ends 8, 9.

In the manufacture of tubes stretches in a laminator is "konti" 5 of 3 cylinders of 6 structures a hollow block and after taking out the mandrel bar, which makes a chuck bar clamping device moving towards forward and backward, as reduced as a nodule in both units of structure 6a, 6b of the extractor laminator 6, while reducing in the massive lamination also the "konti" laminator 5 of 3 6-structure cylinders such as the extractor laminator 6 the bar steel by diameter reduction. Before the nodule is manufactured reduced or reduced steel bar in a custom laminator or Stretch reduction well 10 is just rolled to give a tube or a bar, and the genre is taken to laminate in an oven to further heat 11 to the necessary temperature.

A cutting saw 12 positioned on the side of custom laminator outlet, or stretch reduction, cut the finished tube or the finished steel bar to the desired lengths. The finished lengths are passed to continued on a cooling bed 13. If you have to laminate, on the contrary, the steel bar to give a wire, the steel bar is delivered through an extension of the roller path of cooling bed 14 to a block of wire 15.

The described universal rolling mill allows, by consequently, laminate seamless tubes as well as also bars or wires. In this case they are exchanged before, in the massive lamination in the 3-cylinder "konti" laminator 5 of 6 structures, the cylinders configured for lamination of the tubes with a calibration for them, against the cylinders calibrated for a massive laminate and the mandrel bar is placed in out of order position, for example it is put on the device for holding the mandrel bar in its starting position withdrawal.

Claims (9)

1. Procedure for obtaining seamless wires, bars or tubes in a rolling plant for the lamination of heated metallic sort, optionally comprising in view of the rolling direction a perforation laminator, a stretching laminator of various structures as a stage main stretch (4), a rolling mill (6), a finishing rolling mill (10) and a wire rolling block (15) as well as front, interposed and rear devices, such as an oven for pre-heating and additional heating (11) , roller paths and a cooling bed (13), characterized in that a 3-cylinder "konti" laminator is used in the main stretching stage (4) and is well used for rolling holes in obtaining pipes such as also for mass lamination in obtaining bars, wires and the like, whereby a mandrel bar used for laminating holes is carried in mass lamination in an out-of-service position and steel bar cylinders are exchanged with calibrated cylinders for further reduction of the usual diameter in the rolling of pipes against calibrated cylinders for rolling of pipes. 2. Method according to claim 1, characterized in that a 3-cylinder "konti" laminator (3) whose perforating cylinders for mass rolling with a bar is also used for a drill train previously arranged to the main stretching stage (4) of dome for deviated holes, they are exchanged against steel cylinders in bars prepared with cylinders with a usual diameter reduction in the rolling of steel cylinders in bars. 3. Laminating plant for the lamination of metal heated to give wire, bars or seamless pipes, comprising in view of the direction of lamination optionally a perforating train, a laminator of several structures as the main stretching stage, a laminator extractor, a finishing rolling mill and a wire rolling block as well as previous, intermediate or subsequent devices, such as a preheating and additional heating furnace, roller paths and a cooling bed, characterized in that the main stretching stage (4) shows a 3-cylinder "konti" laminator (5) of various structures formed for the housing of steel bar cylinders and tube cylinders and a device (7) for the removal of the mandrel bar. 4. Laminating plant according to claim 3, characterized in that the drill train (3) disposed before the main stretching stage (4) is configured as a 2-cylinder inclined laminator or 3-cylinder inclined laminator for the accommodation of bar cylinders of steel or perforating cylinders and is equipped with a device for the elimination of the mandrel bar. 5. Rolling plant according to claim 3 or 4, characterized in that a speed number regulation is assigned to the 3-cylinder "konti" laminator (5) of the main stretching stage, which regulates both the cylinder speed numbers common in tube cylinders as well as steel bar cylinders. 6. Lamination plant according to one of claims 3 to 5, characterized in that the extractor laminator (6) shows two structural units (6a, 6b) positioned at a distance from each other with a scissors for the ends (9) that can be inserted into each other. 7. Laminating plant according to one of claims 3 to 6, characterized by an additional heating furnace (11) following the extractor laminator (6). 8. Rolling plant according to one of claims 3 to 7, characterized by a custom laminator and / or stretching by reduction positioned behind the additional heating furnace (11) as a finishing mill (10) for tubes and bar steel . A rolling plant according to one of claims 3 to 8, characterized by an extension of the roll path (14), which leads to the wire block (15) positioned behind the cooling bed (13).