US2653497A - Rolling mill turn-up guide - Google Patents

Description

Patented Sept. 29, 1953 ROLLING MILL TURN-UP GUIDE Walter A. Ebert, Dormont, and Regis A. Connelly,

Bethel Township, Allegheny County, Pa., assignors to .l ones & Laughlin Steel Corporation,- Pittsburgh, Pa., a corporation of Pennsylvania Application June 8, 1950, Serial No. 166,909

2 Claims.

This invention relates to turn-up guides used in the hot rolling of steel and other metals and is more particularly concerned with turn-up guides used to turn bars of elongated cross-section into proper position for rolling into prismatic shapes.

The rolling of bars of prisrnatic shapes is usually accomplished in a succession of passes which produce alternately an oval or diamond section and a prismatic section as the metal is rolled into final shape. These oval or diamond sections will be referred to hereafter as elongated sections, as their precise 4contour is not important to our invention. The bar emerges from an elongated pass with the long axis of its cross-section more or less parallel to the axes of the rolls, which are usually horizontal, and must be turned or twisted through 90 so that it will be introduced into the next pair of rolls with the long axis of its cross-section perpendicular to the axes of the rolls. After the bar of elongated section is introduced into the following pass, it must also be prevented from turning over. It is therefore necessary to provide mills for rolling bars of this type with means between successive stands for the two purposes of twisting the bar into proper position for rolling, and holding the bar in this position as it passes through the re ducing rolls.

Guides which accept a bar of elongated section ,f

with the long axis of its cross-section horizontal and twist such a bar through 96 are well known. However, a bar leaving a pass which has reduced it to an elongated cross-section does not always reach the guide with the long axis of its crossy section in the same plane in which it left the preceding stand. This is particularly true in a mill which is provided with a run-out table between groups of stands, or a mill in which the semi-nished bars are moved across a transfer table from one group of stands to another, which may be parallel to but are not aligned with the first group of stands. When a bar of elongated cross-section has left an intermediate pass and lies upon a runout table or transfer table as above mentioned, its position is not subject to the degree of control which exists While some portion of it is between the rolls of a pass. This is most noticeably true of a transfer table Where bars are moved laterally by means such as dogs attached to continuous belts or chains. The transferring means tend to turn the bars over and may very easily bend or kink the hot bars, so that the ends of the bars which must enter the next pass may well be twisted to a consider- 2 able degree. Such a bar, if suiiiciently twisted or warped, may not enter a guide having an elongated entry opening with its long axis parallel to the axes of the rolls of the preceding stand.

If the hot bar will not enter the guide, it buckles or cobbles, which of course necessitates a shutdown of the mill. It is an object, therefore, of this invention to provide a turn-up guide which will accept an incoming bar of elongated crosssection regardless of the twist or warp of such bar, turn it into the proper position for the next pass, and hold the bar in this position for further reduction. It is another object to provide a turn-up guide which will accommodate bars of slightly diiierent cross-sections, such as diamonds and ovals. It is another object to provide a turn-up guide which will accommodate a range of sizes of bars of the cross-sections above mentioned. Other objects will appear in the course of the description of our invention.

Our turn-up guide comprises an elongated metallic housing provided with a longitudinal bore. The housing may be made in two parts, split along a longitudinal plane, or may be formed integrally. The material for the housing may be cast iron, or steel, carbon or alloy, although we do not limit ourselves to any particular material.

Reference is now made to the attached ngures, which illustrate a present preferred embodiment of our invention:

Figure 1 is an elevation in section of our turnup guide taken on the plane I-I of Figure 2;

Figure 2 is a plan view of one-half of our turnup guide, which for convenience is made in two sections of opposite hand but otherwise identical;

Figure 3 is an end elevation of our turn-up guide taken at the entry end; and

Figures 4, 5 and 6 are cross-sections taken on the planes IV, V and VI of Figure l.

It will be observed from` Figures 1, 2 and 3 that the entry end I of our turn-up guide tapers or tunnels to a circular bore 2, the diameter of which is greater than the long dimension of the bar of elongated cross-section 3. A tapered pro jecting rib l of triangular cross-section is formed in one side of our turn-up guide beginning at approximately the entrance to the circular bore 2 or shortly therebehind. The height of this rib 4 increases gradually until the diametral distance from its vertex to the opposite side of the guide is less than the major axis of the bar to be turned, which occurs at the point 5 on Fig ure 2. From this point on, the top of the projecting rib l remains parallel to the walls of our 3 guide. The angle included between the sloping sides or" our rib, however, increases gradually and uniformly from the beginning of the rib Until the remaining opening in the guide roughly approximates that of the cross-section of the bar. This is reached at or near the exit end of our guide, such as the point 6 in Figure 2. The successive cross-sections shown in Figures a, 5 and 6 illustrate the formation of our guide. In Figure 4 the projecting rib formed by the two inclined faces l-l is small, and includes only a small angle A between these faces. The remainder of the cross-section is almost a complete circle 8. In Figure 5 the projection formed by the inclined faces 9--9 has reached its maximum height, and the angle B included between these faces is much greater than in Figure 4. The remainder of the cross-section IS is somewhat greater than a semi-circle. In Figure 6 the angle C included between the inclined faces Il-II is much greater than 180, and these faces now form a trough. The arc I2, which forms the remainder of the cross-section, is only slightly greater than a quadrant. The exit opening bounded by the intersecting lines I I-II and the arc of a circle I2 is seen to follow roughly the cross-section contour of the bar 3 and prevents this bar from turning over in the succeeding pass.

YOur turn-up guide, as has been mentioned, is located at the end of a run-out or transfer table or other location where partly rolled bars have left one group of stands and have not entered the next following group. Its operation may be understood by reference to the above-mentioned drawings. A bar 3 rolled to a diamond shaped cross-section enters the turn-up guide at its entry end I, which, as has been described, tapers or funnels to a bore 2 of circular section. Since this bore 2 at the entry end of the guide is circular, it will accept a bar regardless of the relative inclination of the bar cross-section. .In Figure 3 the bar 3 is shown as entering with its long axis tilted slightly clockwise from the horizontal, but our guide will accept an entering bar with its long axis .in any position When the bar reaches .a position just beyond the entry end of our guide at which the tapering triangular rib 4 begins to arise, an edge of the bar will be engaged by this rib and deflected either above or below the rib,

dependent upon the original inclination of the I bar cross-section. In Figure 4 the bar 3 is shown as deflected below the triangular rib formed by the plane sides 1 1. As the bar progresses through the guide, the gradual constriction of the bore caused by the gradually increasing angle included between the plane sides of the rib forces the bar toward an upright position. In .Figure 5 .the bar 3 is seen to have been 'rotated ina counterclockwise direction .from 4its position in Figure 4. If the bar 3 in Figure 4 .had entered so that its edge lay on top ofthe triangular rib formed by the plane sides I-l., it would have been rotated in a clockwise ldirection as it continued through the guide. -As has been mentioned previousli, the triangular rib vgradually increases in height until the distance from its vertex to the :opposite side of the guide is less than the length 'of the major axis of the bar. When the bar reaches the exit end or" the `guide, the bore or the latter has gradually contracted to the section shown in Figure 6, which holds the bar 3 `upright regardless of whether its rotation has been clockwise or counterclockwise. In most cases, therefore, our turn-up guide rotates the entire bar about its longitudinal axis as the bar passes through and does not twist any one portion of the bar relative to the remainder of the bar. In some cases, however, such as very hot bars of relatively small cross-section and moving rather rapidly, our guide may in fact twist the bar as it passes through.

The turn-up guide of our invention may be used either with or without a conventional bar guide to maintain the bar in proper position as it passes through the following rolls. If the turn-up guide is to be used alone, the contour of its exit end must nt the contour of the bar quite closely. If a separate bar guide is used following the turn-up guide, the contour of the exit end of the latter is much less critical. Since our turn-up guide is considerably larger and heavier than conventional bar guides, and therefore more cumbersome to change as bars of various sections are rolled, we find it more practical to use separate, easily changed bar guides for each size or shape of bar to be rolled, and design our turn-up guide'to accommodate a range of bar sizes. It is most desirable, of course, to design the turn-up guide to accommodate the same range of sizes as may be rolled with a given set of mill rolls. In this way the turn-up guide and rolls are changed together.

The embodiment of our turn-up guide which we have illustrated and described was designed particularly for a bar of diamond shaped section. This guide will also operate successfully with bars of oval or similarly elongated cross-section of approximately the same areas, but somewhat better results may be obtained if the guide construction is modified slightly to adapt it to the particular section being rolled. In a guide for an oval section, for example, the sides of the trough near the exit end, indicated by lines I I--II in Figure 6, could be concave rather than plane. Furthermore, the arc I2 of the bore circle could be contoured to a more oval form so that the exit open- .ing of the guide would approximate more closely the shape of the bar cross-section. Modications of this sort will readily suggest themselves to those skilled in the art.

Although we have described and illustrated the present preferred embodiment of our invention, it will be understood that the invention is not limited thereto but may be otherwise embodied or practiced within the scope of our claims.

We claim:

,1. VA rolling mill turn-up guide for a bar having unequal major and minor cross-sectional diameters comprising a housing provided with a longitudinal bore of circular cross-section at its entry end, the periphery of each successive bore cross-section being formed by an arc of a circle and two equal lines intersecting on a diameter of the circle, the lengths of these lines increasing gradually vfrom entry to exit end of the guide, the vertex angle included between the lines increasing from an acute angle at the entry end to an angle greater than .180 at the exit end.

2. A rolling mill turn-up guide for a bar having unequal major and minor cross-sectional diameters comprising a housing provided with a longitudinal bore of circular cross-section at its entry end, the periphery of each successive bore :cross-section being formed by an arc or" a circle :and two equal lines intersecting on a diameter `of the circle, the lengths of these lines increasing gradually from entry to exit end of the guide, the diametral distance from this point of inter- -section to said arc Adecreasing gradually from the entry end of the guide to a point intermediate its ends and remaining substantially constant from this point to the exit end of the guide, the vertex angle included between the lines increasing from an acute angle at the entry end to an angle greater than 180 at the exit end. WALTER A. EBERT. REGIS A. CONNELLY.

References Cited in the flle of this patent /Number FOREIGN PATENTS

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