RU2310527C2 - Strip lengthwise rolling method and apparatus for performing the same - Google Patents

Abstract

FIELD: methods and apparatuses providing predetermined value of rolling effort.

SUBSTANCE: method comprises steps of mounting rolls between plates with permanent magnets having stationary and movable blocks arranged equidistantly relative to rolls surface. Rolling stand includes at least one pair of magnetic plates with permanent magnets arranged equidistantly relative to rolls surface at both sides of rolling plane. Said plates have stationary and movable blocks and mechanism for their mutual motion. It allows shunt or neutralize magnetic fluxes.

EFFECT: lowered size of rolling stand, reduced power losses at creating rolling effort, improved quick action.

4 cl, 3 dwg

Description

The present invention relates to rolling production and can be used in the shops for hot and cold rolling of non-ferrous and ferrous metals and alloys, as well as for rolling non-metallic materials.

A known rolling method, including the distribution along the roll barrels of the compensated rolling force using electromagnetic forces of attraction and / or repulsion between the rollers placed in an external magnetic field across the magnetic flux vector [1].

The disadvantage of this method is the passage of magnetic flux along the work rolls and magnetic circuits having a long length. At the same time, up to 80% of the energy supplied to the coils of the electromagnets is expended on the magnetic flux to create a given induction in the working gap "δ", which provides the necessary rolling force. In addition, the magnetic flux requires massive magnetic cores, as a result, the weight and dimensions of the cage grow.

There is also known a method of longitudinal rolling and a stand for its implementation [2], which includes passing electric current along the rolls and creating a rolling force by arranging the poles of electromagnets or magnets between the diametrical plane of the roll and the rolling plane, the magnetic field vector being directed along the diametrical plane of the rolls. The rolling mill for implementing the method is equipped with massive electromagnets and / or magnets with magnetic cores. The disadvantage of this method is the conduct of magnetic flux to the working gap "δ" along the magnetic circuits having a large length and size, which consumes most of the energy supplied to the excitation coils. The disadvantages of the known rolling stands include: large dimensions and weight due to the presence of massive magnetic cores and magnets, inertia when regulating the current in the excitation coils due to the large dimensions.

The objective of the present invention are: to reduce the size and weight of the stand, a sharp decrease in energy loss when creating a rolling force, ensuring the speed of an automatic control system for power and electromagnetic parameters of the stand. To achieve this goal, it is necessary that the magnetic fluxes supplied to the working gaps "δ" between the rollers and the poles of the electromagnets and / or magnets, have the smallest possible paths from the source of the magnetic field (electromagnet, permanent magnet) to the rollers.

This problem is achieved by the fact that the rolls are placed between multipolar plates with permanent magnets located equidistant to the surface of the roll with gaps "δ", and the rolling force is controlled by moving the movable and fixed blocks of the magnetic plate relative to each other.

A rolling stand containing a bed, rolls, sources of magnetic fields is equipped with at least one pair of plates with permanent magnets located equidistant to the surface of the rolls on both sides of the rolling plane, containing a movable and fixed blocks and a mechanism for their relative movement relative to each other.

In addition, the magnetic plates at one end are connected to the frame of the stand using a hinge located on the same axis with the horizontal axis of the roll, and the other end is connected to the rods of hydraulic cylinders resting on the frame of the stand, the mechanism for moving blocks of the magnetic plate is made in the form of a lever pivotally connected to device for turning it. Magnetic plates along the roll barrel can be single-section and multi-section, which allows you to smoothly change the magnetic induction along the roll barrel due to the partial or complete neutralization of the magnetic flux of individual sections.

The proposed method is characterized in that in order to create a force, the rolls are placed between plates with permanent magnets located equidistant to the surface of the rolls, and the rolling force is controlled by shunting, displacing the movable and fixed blocks of the magnetic plate relative to each other.

When the magnetic plate is turned on, magnetic fluxes appear on its surface, closing on the rolls through the gaps "δ" along the shortest path. Thus, there is no need for energy costs for conducting magnetic flux through magnetic circuits and rolls, which occurs when using II or III-shaped electromagnets with large excitation coils.

To implement the method proposed rolling mill, schematically shown in figure 1. Figure 2 shows a view And on a multi-section plate, figure 3 is a longitudinal section of the plate (node I). The cage consists of a bed 1, work rolls 2, pressure rolls 3 mounted for vertical movement, plates 4 with permanent magnets mounted equidistant to the surface of the rolls 3. One end of the plate 4 is connected by a hinge 5 to the bed 1 of the cage, the horizontal axis of the hinge 5 coincides with the horizontal axis of the roll 3. The other end of the plate 4 is pivotally connected to the rod 6 of the hydraulic cylinder 7, resting on the frame 1. The magnetic plate 4 has a movable 8 and a fixed 9 magnetic blocks, the movement of which relates flax each other is provided a lever mechanism, comprising, for example, rack and pinion device 10, driven by a lever 11 pivotally connected to the device 12 for its rotation. Control of plates, for example, with barium oxide magnets is carried out by the method of neutralizing magnetic flux F.

When the magnets 13 are in the movable 8 and stationary 9 blocks of the magnetic plate 4 in a position in which the magnetic flux Φ generated by the individual magnets 13 is closed through the gap "δ" on the roll 3, corresponds to the "on" position and provides the required attractive force Q of the roll 3 to the magnetic plate 4.

When moving the moving block 8 relative to the stationary 9 (for example, to the right) one step, the magnetic fluxes Φ will pass inside them without going outside, i.e. to the rolls. In this case, the magnetic plate is in the off position. By changing the polarity of the poles 14 inside the plate 4 by neutralizing (full and partial), you can change the rolling force R.

When using plates 4 with cast magnets to regulate the rolling force P, a bypass method is used [3].

The rolling method is as follows. Magnetic blocks by means of devices 12 (for example, hydraulic cylinders) and levers 11 connected to the rack device 10 are set to the “off” position, in which there are no fluxes Ф on the surface of the magnetic plates 4. Using the hydraulic cylinders 7, the magnetic plates 4 are rotated around the hinges 5 and an initial clearance "δ" is set between the rollers 3 and the plates 4. After setting the gap, the magnetic blocks are set to the "on" position, while magnetic fluxes Φ appear on the surface of the plates, penetrating the air gaps "δ" and the surface of the rolls 3 without spreading deeper into the roll 3 and without intersecting the work rolls 2, which greatly reduces their path .

The regulation of the rolling force P is carried out by partially (or completely) moving the movable block 8 relative to the stationary 9, neutralizing part or all of the fluxes Ф on the surface of the magnetic plates 4.

It should be noted a number of advantages of the proposed rolling method:

1. The weight of the magnetic plates is much less than the U-shaped electromagnets.

2. The operation of magnetic plates is completely safe.

3. Magnetic plates do not consume electricity from an external current source.

4. Magnetic fluxes are local, do not penetrate deep into the roll, do not cross the work rolls and practically do not magnetize them due to the absence of leakage flows in the space surrounding them.

5. Metal dust, scale, wear products of the rolls, as in traps, accumulate in the working gaps "δ", without falling into the deformation zone and onto the strip, periodically being washed out of them by cutting fluid.

6. During the rolling process, rolls 2, 3 constantly wear out and the air gap "δ" changes. In the proposed design, during the rolling process (and during transhipments), the gaps "δ" are maintained constant by moving (turning) the plates 4 with the help of hydraulic cylinders 7 around the hinges 5.

The proposed method of longitudinal rolling and the stand for its implementation can significantly reduce the energy costs of creating magnetic fields, reduce the weight and dimensions of the stand, simplify management, improve the operational characteristics of the stand, reliable in operation, and also improve the quality of the finished hire.

The application of the proposed stand design increases the efficiency magnetic system and technological capabilities of the stand.

Information sources

1. RF patent No. 2139153, bull. No. 28, 10/10/1999

2. RF patent No. 2146971, bull. No. 9, 03/27/2000

3. Konstantinov O.Ya. "Magnetic technological equipment." Leningrad. "Engineering". LO, 1974

Claims (4)

1. The method of longitudinal rolling, including the use of adjustable magnetic fluxes to create a rolling force by the rolls, characterized in that the rolls are placed between plates having movable and fixed blocks with permanent magnets that are equidistant to the surface of the rolls, and the rolling force is controlled by shunting or neutralizing magnetic flux displacement of the movable and fixed blocks relative to each other. 2. The method according to claim 1, characterized in that the magnetic induction along the roll barrel is changed by partially or completely neutralizing magnetic fluxes in individual sections of the plate. 3. A rolling stand, including a bed, rolls and sources of magnetic fields, characterized in that it is equipped with at least one pair of plates with permanent magnets located equidistant to the surface of the rolls on both sides of the rolling plane, containing movable and fixed blocks with permanent magnets and the mechanism of their mutual movement relative to each other, with the plates at one end connected to the frame of the stand using a hinge located on the same axis with the horizontal axis of the roll, and the other end connected to the rods hydraulic cylinders resting on the frame of the stand, and the mechanism for moving blocks is made in the form of a lever pivotally connected to the device for its rotation. 4. The rolling stand according to claim 3, characterized in that the plates are made single-section or multi-section and are equipped with autonomous mechanisms for moving the movable block relatively stationary in each section of the plate.

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