RU2254946C1 - Assembly for axially fixing chock in rolling roll journal - Google Patents

Abstract

FIELD: axial fixation of bearings and chocks in journals of rolling rolls of wide strip rolling mills.

SUBSTANCE: assembly includes chock supporting bearing unit, inner and outer lids provided with seals, mounted in journal of roll and secured to chock; spacing ring mounted in key of rolling roll, members for axially fixing chock mounted in annular turning of roll journal. Members for axially fixing chock are in the form of two cover plates with inner cylindrical ribs arranged diametrically opposite relative to vertical axis of chock in annular turning of roll journal. Cover plates are mounted with use of bolts with possibility of motion in outer end of spacing ring. Thickness of cover plates exceeds that of inner cylindrical ribs that is why stop cylindrical surfaces are formed. Said surfaces are joined at both sides of annular turning of roll journal with outer surface of journal. Inclined straight different-length slits are formed in cover plates symmetrically relative to vertical axis of chock. Said slits are inclined by different angles to horizontal axis of chock; lower slits are inclined by large angle and upper slits are inclined by small angle. Length values of chords in cover plates between crossing points of different radius circles passed from center arranged in roll axis with axes of slits along their whole length are the same and equal to distance between mounting bolts of cover plates in spacing ring. Countersunk recesses for bolt heads are formed in ends of slits in bolt mounting places on both planes of cover strip surface.

EFFECT: shortened duration of idle periods and of roll change periods, lowered consumption of rolls and bearings, enhanced quality of rolled strips, improved reliability of assembly for axially fixing bearing and efficiency of rolling mill.

6 dwg

Description

The invention relates to rolling production and can be used for axial fixation of pillows on the necks of the working rolls of rolling mills.

Known node axial fixation of the pillow on the neck of the roll roll (analogue), including a pillow with a bearing mounted in it, mounted on the neck of the roll and mounted on the pillow of the inner and outer covers with seals, a distance ring mounted on the key on the neck of the roll, and means of axial fixation pillows installed in an annular groove made on the neck of the roll (see A.A. Korolev. Mechanical equipment of rolling and pipe shops. M., Metallurgy, 1987, p. 70, Fig. II.14).

The axial fixation unit of the analogue includes two half-rings with an external thread installed in an annular groove on the neck of the roll, onto which an outer integral ring is wound, holding the pillow with bearing from axial displacement on the neck of the roll. The disadvantage of this analogue is the unwinding of the outer ring and the loss of threaded half rings from the groove on the roll neck, which leads to axial runouts and roll displacement relative to the bearing, destruction of the bearing and roll and severe accidents of the rolling mill associated with large production losses.

The closest technical solution (prototype) is an axial fixation unit for the pillow on the neck of the roll, including a pillow with a bearing installed in it, mounted on the neck of the roll and mounted on the pillow of the inner and outer covers with seals, a distance ring mounted on the key on the neck of the roll, and means of axial fixation of the pillow installed in an annular groove made on the neck of the roll (see AS USSR, No. 1772953 A1, M. Cl. V 21 V 31/02, 1990).

The axial fixation means of the prototype include a spacer nut screwed onto the spacer ring, a shaped key installed in the keyway on the roll neck and mounted externally on the spacer nut, and half rings mounted in the annular groove on the roll neck. A conical recess is made in the spacer nut, interacting with the outer surfaces of the half rings.

The disadvantage of the analogue is the unwinding or tightening of the spacer nut under the action of moments of inertia arising from acceleration, braking and other unsteady rolling modes. This leads either to a violation of the fixation of the pillow with the bearing on the neck of the roll, or to over-tightening of the bearing in the pillow. In the first case, half-rings may fall out of the annular groove on the neck of the roll, which causes the destruction of the bearing and breakage of the roll. In addition, the weakening of the mounting of the pillow on the roll causes its axial runout and the appearance of transverse shear defects on the surface of the rolled strips, reducing the quality of the strip.

In the second case, overtightening of the bearing also leads to its quick failure and emergency downtime of the rolling mill.

The aim of the present invention is to increase the reliability of the axial fixation unit of the pillow on the neck of the rolling roll, reducing emergency downtime, consumption of bearings and rolls, increasing the productivity of the rolling mill and the quality of the rolled strips.

This goal is achieved in that the means of axial fixation of the pillow are made in the form of two strips with inner cylindrical ribs located diametrically opposite to the vertical axis of the pillow in the annular groove on the neck of the roll, the strips are bolted, the thickness of the strips is thicker than the thickness inner cylindrical ribs, due to which persistent end cylindrical surfaces are formed on the planks, mating on both sides of the rings grooves on the neck of the roll with the outer surface of the neck, on the strips symmetrically with respect to the vertical axis of the pillow, inclined rectilinear slots of various lengths and with different angles of inclination to the horizontal axis of the pillow are made — large for the lower slots and smaller for the upper, the length of the chords on the bars between the points of intersection of circles different radius, drawn from the center located on the axis of the roll, with the axes of the slots along their entire length is the same and equal to the distance between the bolts securing the strips on the spacer ring, and countersink recesses for bolt heads are made on the ends of the slots in the places where the bolts were installed on both flat surfaces of the slats.

The invention is illustrated by drawings, which depict:

figure 1. The axial fixation unit of the pillow on the neck of the rolling roll is an axial section.

Figure 2. View along arrow A in figure 1.

Figure 3. The section along the line BB in figure 1.

figure 4. The section along the line BB in figure 2.

figure 5. Plan view (pos. 10).

6. The cross-section of the bar along the line GG in figure 5.

The axial fixation unit of the pillow on the neck of the roll roll includes a pillow 1 with a bearing 2 installed in it, mounted on the neck 3 of the roll. The inner 4 and outer 5 covers with seals are bolted to the pillow. A spacer ring 6 is mounted on the neck of the roll, fixed from turning by a key 7.

An annular groove 8 is made on the neck of the roll, in which two strips 9 and 10 are installed diametrically opposite to the vertical axis of the pillow. The strips are identical in design and interchangeable. On the planks, inner cylindrical ribs 11 are provided, located in the annular groove 8. A dowel 7 is located opposite one of the planks and is located in adjacent keyways on the inner cylindrical surface of the distance ring and the outer surface of the roll neck.

The thickness S _{p of the} strips is greater than the thickness S _{p of the} inner cylindrical ribs 11 (Fig.6). Due to this, persistent end cylindrical surfaces 12 of radius R _s are formed on the planks, mating on both sides of the annular groove 8 on the neck of the roll with the outer surface of the neck.

On the strips symmetrically relative to the vertical axis of the pillow, inclined rectilinear slots 13 and 14 (see FIGS. 2, 5) of various lengths l ₁ and l ₂ and with different angles of inclination α and β to the horizontal axis of the pillow are made — a large angle for the lower slots and a smaller angle - for the top.

The length of the chords on the planks between the points of intersection of circles of different radii drawn from the center 0 located on the axis of the roll with the axes of the slots within their lengths l ₁ and l _{2 is the} same.

Figure 5 shows the chords A ₁ A ₂ and B ₁ B _{2 of the} same length equal to 2a drawn through the points A ₁ A ₂ and B ₁ B _{2 of the} intersection of circles of radii R ₁ and R ₂ . The length l _{2 of the} slot 14 is greater than the length l _{1 of the} slot 13, and the angle α is greater than the angle β. Due to the constancy of the length of the chords between the points of intersection of the axes of the slots and circles of different radii R ₂ and R ₁ when the points A ₁ and A ₂ move to the points B ₁ and B _{2, the} bar is shifted to another position (shown by the dotted line) equidistant from the initial position and completely leaves an annular groove 8 on the neck of the roll along the entire length of the cylindrical rib 11, freeing the pillow from axial fixation and ensuring its free removal from the neck of the roll when replacing it with a new one.

The straps 10 are fixed with the ability to move on the outer end of the distance ring with bolts 15. When designing an axial fixation unit, the length of the chords of circles of radii R ₁ and R _{2 is} taken to be equal to the distance 2a between the bolts of the brackets. The bolts are located symmetrically relative to the horizontal axis of the pillow (see figure 2 and 5) at a distance from it "a" equal to half the length of the chord. In this case, the location of the strips and bolts is convenient for their maintenance.

The holes in the distance ring 6 for the bolts 15 for fastening the strips 9, 10 are located at the ends of the slots 13 and 14 of the strips on the circumference of a larger radius R ₁ (see figure 5). On both flat surfaces of the planks at the places of installation of the bolts 15, countersinks 16 are made under the head of the bolts by countersinking. This allows you to make the slats interchangeable, swapping them with a mirror image.

The axial fixation of the pillow on the neck of the roll is carried out by moving the strips 10 with grooves 13 and 14 relative to the bolts 15 and introducing them into the annular groove 8 on the neck of the roll. In the initial position, the slats are lowered by their own weight, and their ribs 11 are removed from the willow of the annular groove. The bolts 15 are partially unscrewed from the distance ring 6 so that their heads are withdrawn from the recesses 16 beyond the planes of the planks. The straps are in their lowest position and suspended from the spacer ring 6 by bolts 15. The open position of the strap is shown in FIGS. 4 and 5 by dashed-dotted lines. The hole in the ring 6 is free to put on the pillow 1 with covers 4, 5, bearing 2 and ring 6 on the neck of the roll.

After putting on the pillows, the bolts 15 are slightly tightened on the strips 10 and, by lightly tapping the strips from below, are inserted with their inner cylindrical ribs 11 into the annular groove 8 on the neck of the roll. To reduce the resistance to movement of the planks, the inclination angle β of the upper slots 14 is taken to be greater than the friction angle between the bolts and the slots. In this case, when the bolts 15 are loosened, the straps freely move away from the roll neck under the action of their own weight, and when connecting the straps to the roll neck, a very small manual force is required to move them.

The angle α is calculated based on the value of the accepted angle β in accordance with the principle of constant chord length on circles of different diameters between the axes of the slots 13 and 14. The angle α is greater than the angle β, therefore, the main resistance to the movement of the slats is created on the upper slots 14, which determines the accepted approach to the choice of angle β.

In the closed position, the straps 9 and 10 are connected by persistent end cylindrical surfaces 12 of radius R ₃ with the outer surface of the neck of the roll located on both sides of the annular groove 8, and the ribs 11 are located in the groove and hold the straps together with the spacer ring 6, bearing 2 and pillow 3 on the neck of the roll from axial displacement.

After closing the strips, the heads of the bolts 15 are over the recesses 16. The bolts are screwed until their heads stop in the bottom of the recesses, as shown in Fig. 4 in solid lines. As a result, the straps are securely held in the annular groove 8 and securely fix the pillow on the neck of the roll, since the heads of the bolts 15 located in the recesses 16, prevent the movement of the straps through the slots 13 and 14.

When removing the pillow from the neck, the roll is set so that the strips 9, 10 are located on the horizontal axis of the pillow (see figure 2). Unscrew the bolts 15 until their heads exit from the recesses 16 beyond the flat surfaces of the slats. Under the influence of their own weight, the slats lower, their cylindrical ribs come out of the annular groove 8 and release the pillow from fixing. When removing the pillow, set so that the key 7 is in the upper part of the neck, as shown in figures 1 and 3. When removing the pillow, the key remains freely in the keyway on the neck of the roll. In this case, the inner ring of the bearing 2 freely passes over the key.

When closing the strips, the key 7 is preliminarily shifted on the roll neck to the extreme position, freeing the annular groove 8 on the neck, and the strap 10 holds the key in the combined keyways of the neck 3 of the roll and the distance sleeve 8 during the work of the roll.

When the strips 9, 10 are moved, they deviate from the initial position by a certain angle γ (see Fig. 5). However, as already noted above, the movement of the annular ribs 11 occurs equidistantly relative to the bottom of the annular groove 8 on the neck of the roll, which guarantees the complete exit of the annular ribs 11 from the annular groove along their entire length and the full opening of the slats.

The proposed site axial fixation of the pillow on the neck of the roll is characterized by high reliability, simplicity of design, low cost and provides a significant reduction in the complexity of preparing the rolls for rolling. Violation of the axial fixation of the pillow during unsteady modes of rolling-acceleration, braking, reverse and others. The required clamping force of the roller bearing is maintained constant between the spacer ring 6 and the restrictive inner protrusion on the inner seating surface of the pillow under the outer bearing ring. This helps to increase the durability of the bearings and reduce their consumption, reduce emergency downtime of the rolling mill and increase its productivity. Axial runout of rolls is excluded, which reduces the number of breakdowns and consumption. Transverse shear defects on the surface of rolled strips are reduced and their quality is improved.

Thus, the application of the proposed technical solution allows to achieve the goal of the invention.

Claims (1)

An assembly of axial fixation of a pillow on the neck of a roll, including a pillow with a bearing installed in it, mounted on the roll neck and fixed on the pillow of the inner and outer covers with seals, a spacer ring mounted on a key on the neck of the roll, and means of axial fixation of the pillow installed in an annular groove made on the neck of the roll, characterized in that the means of axial fixation of the pillow are made in the form of two strips with inner cylindrical ribs located diametrically opposite relative to the vertical axis of the pillow in the annular groove on the neck of the roll, the strips are fixed with the possibility of movement on the outer end of the distance ring with bolts, the thickness of the strips is greater than the thickness of the inner cylindrical ribs, due to which the cylindrical thrust surfaces are formed, mating on both sides of the annular groove on the neck of the roll with the outer surface of the neck, on the strips symmetrically with respect to the vertical axis of the pillow, inclined rectilinear slots of various lengths and with different angles are made the inclination to the horizontal axis of the pillow - a large angle for the lower slots and less for the upper ones, the length of the chords on the strips between the points of intersection of circles of different radii drawn from the center located on the axis of the roll with the axes of the slots along their entire length is the same and equal to the distance between the bolts fastening the strips on the spacer ring, and countersink recesses for the bolt heads are made on the ends of the slots in the places where the bolts were installed on both planes of the surface of the strips.

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