Device and method for cooling a cross-cutting shear in hot strip mills

Abstract

A device (100) and a method for cooling a knife-bearing element (102.1, 102.2) of a cross-cutting shear (103), which is in particular installed in a hot rolling mill, are described. When the knife-bearing element (102.1, 102.2) is at standstill, at least one guard device (105) is positioned in a cooling position (K) between the knife-bearing element (102.1, 102.2) and a roll strip (101) running continually through the roller mill, such that a side of the knife-bearing element (102.1, 102.2) opposite the roll strip is shielded by the guard device (105).

Claims

1.-19. (canceled)

20. A device (100) for cooling at least one knife-bearing element (102.1, 102.2) of a cross-cutting shear (103) installed in a rolling mill, in particular in a hot rolling mill, comprising: a guard device (105); and a guide device (106) on which the guard device (105) is movably guided and can thus be moved between a cooling position (K) and a cutting position (S), wherein the guard device (105) is positioned in the cooling position (K) between a knife-bearing element (102.1, 102.2) and a roll strip (101) which continuously runs through the rolling mill, such that a side of the knife-bearing element (102.1, 102.2) opposite the roll strip (101) is shielded by the guard device (105), wherein the guard device (105) in the cutting position (S) is spaced apart from a field of movement (MK) of the knife-bearing element (102.1, 102.2), such that the guard device (105) is not touched by such knife-bearing element (102.1, 102.2) during movement of the knife-bearing element (102.1, 102.2) or during cutting of the roll strip (101), wherein the guide device (106) is designed in form of sliding guides (108.1-108.4), which are arranged on both sides of the roll strip (101), wherein the guard device (105) is movably guided with its two end faces on the sliding guides (108.1-108.4), wherein the sliding guides (108.1-108.4) are attached to inner sides of lateral stand frames (104) of the cross-cutting shear (103), wherein a first arc-shaped guide track (109.1) and a second arc-shaped guide track (109.2) are respectively formed in each of the sliding guides (108.1-108.4), wherein a path curve, which is defined by the arc-shaped guide tracks (109.1, 109.2), points convexly outwards with respect to an adjacent knife drum (102.1, 102.2), and wherein the guide tracks (109.1, 109.2) are arranged in a sliding guide (108.1-108.4) in a partially overlapping manner.

21. The device (100) according to claim 20, wherein a width of the guard device (105) transverse to a transport direction (T) of the roll strip (101) corresponds at least to a width of the knife-bearing element (102.1, 102.2).

22. The device (100) according to claim 20, wherein a width of the guard device (105) transverse to a transport direction (T) of the roll strip (101) is greater than a width of the knife-bearing element (102.1, 102.2).

23. The device (100) according to claim 20, wherein a drive device is in operative connection with the guard device (105), in order to move the guard device (105) along the guide device (106) into the cooling position (K) or into the cutting position (S).

24. The device (100) according to claim 23, wherein the drive device comprises an electric motor or a hydraulic cylinder that is in operative connection with the guard device (105), in order to move the guard device (105) along the guide device (106) into the cooling position (K) or into the cutting position (S).

25. The device according to claim 23, wherein the drive device comprises a four-jointed or multiple-jointed mechanism, through which the drive device is coupled to the guard device (105).

26. The device (100) according to claim 20, wherein the guard device (105) is formed in two parts and comprises two shielding elements (110) that—viewed from an inlet side of the roll strip (101) and from an outlet side of the roll strip (101) into or from the cross-cutting shear (103)—are movable for transfer into the cooling position (K) in mirror image in the inlet side or outlet side in such a manner that the shielding elements (110) are positioned adjacent to one another in the cooling position (K) and thereby shield a side of the knife-bearing element (102.1, 102.2) opposite the roll strip (101) from the roll strip (101).

27. The device (100) according to claim 26, wherein each of the two shielding elements (110) has a trough area (111) and a wall area (112), wherein the wall area (112) is arranged at an angle relative to the trough area (111) in cross-section along a width of the roll strip (101).

28. The device (100) according to claim 27, wherein lateral guide pins (113) are attached to side edges (115) of a shielding element (110) both adjacent to the trough area (111) and adjacent to the wall area (112), which guide pins are in engagement with the arc-shaped guide tracks (109.1, 109.2).

29. The device (100) according to claim 26, wherein the guard device (105) is positioned in the cooling position (K) between an upper knife-bearing element (102.1) of the cross-cutting shear (103) and the roll strip (101) which runs continuously through the rolling mill, such that a lower side of the upper knife-bearing element (102.1) is shielded from the roll strip (101) by the guard device (105).

30. The device (100) according to claim 29, further comprising a coolant supply device (114), by means of which a coolant can be introduced from above into trough areas (111) of the shielding elements (110).

31. The device (100) according to claim 30, wherein at least one outflow opening (116) is formed on a side edge of the trough area (111) of a shielding element (110), through which outflow opening the coolant can emerge downwards in a targeted manner.

32. The device according to claim 20, wherein the cross-cutting shear (103) is a drum shear, and wherein a knife-bearing element is formed as a knife drum of the drum shear.

33. The device according to claim 20, wherein the cross-cutting shear (103) is a gate shear.

34. The device according to claim 20, wherein the cross-cutting shear (103) is a crank shear.

35. A method for cooling a knife-bearing element (102.1, 102.2) of a cross-cutting shear (103) installed in a rolling mill, in particular in a hot rolling mill, comprising: arranging, when the cross-cutting shear (103) is at a standstill, at least one guard device (105) in a cooling position (K) between a knife-bearing element (102.1, 102.2) of the cross-cutting shear (103) and a roll strip (101) which continuously runs through the rolling mill, such that a side of the knife-bearing element (102.1, 102.2) opposite the roll strip (101) is shielded by the guard device (105), wherein the guard device (105) is formed in two parts and comprises two shielding elements (110) that are brought in mirror image from an inlet side of the roll strip (101) and from an outlet side of the roll strip (101) into the cooling position (K), in which the shielding elements (110) are positioned adjacent to each other and thereby shield a lower side of the knife-bearing element (102.1) from the roll strip (101), wherein the shielding elements (110) each have a trough area (111); continuously introducing cooling water into the trough areas (111) while the shielding elements (110) are in the cooling position (K); and allowing the cooling water to overflows side edges (115) of the trough areas (111) and flow laterally past the roll strip (101) in a downward direction when the trough areas (111) are fully flooded with cooling water.

36. The method according to claim 35, wherein the guard device (105) is positioned between an upper knife-bearing element (102.1) of the cross-cutting shear (103) and the roll strip (101) which continuously runs through the rolling mill.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 is a perspective view of a device for cooling at least one knife-bearing element of a cross-cutting shear installed in a rolling mill.

[0027] FIG. 2 is a front view of the device of FIG. 1.

[0028] FIG. 3 is a partial perspective view of the device of FIG. 1, along the sectional view along line A-A of FIG. 2, in a cooling position.

[0029] FIG. 4 is a partial perspective view of the device of FIG. 1, along the sectional view along line A-A of FIG. 2, in a cutting position.

[0030] FIG. 5 is a perspective view of a sliding guide that is part of the device of FIG. 1.

[0031] FIG. 6 is a perspective view of a trough-shaped cover that is a part of the device of FIG. 1.

[0032] FIG. 7 is a perspective view of parts of the device of FIG. 1, comprising each of four sliding guides as shown in FIG. 5, and two trough-shaped covers as shown in FIG. 6 arranged between them.

[0033] FIGS. 8-10 are end face views of the device of FIG. 1 along line A-A of FIG. 2, each in different operating positions.

[0034] FIG. 11 is a front view of a drum shear in accordance with the prior art.

DETAILED DESCRIPTION

[0035] With reference to FIGS. 1 to 10, a preferred embodiment of a device 100 and its components, which serves to cool at least one knife drum of a drum shear 103, is explained below. At this point, it should be noted that identical features in the drawing are each provided with identical reference signs. The drawing is merely simplified and shown without scale in particular.

[0036] FIG. 1 shows a drum shear 103 in a perspective view, wherein such drum shear 103 is shown in FIG. 2 in a front view. A roll strip 101 runs through drum shear 103 between an upper knife drum, which serves as the knife-bearing element 102.1, and a lower knife drum, which serves as the knife-bearing element 102.2. In a known manner, such knife drums 102.1, 102.2 are at a standstill if the drum shear 103 is not being used to cut through the roll strip 101.

[0037] The drum shear 103 of FIG. 1 can be equipped with a device 100 in accordance with the invention, with which in particular the upper knife drum 102.1 of the drum shear 103 is cooled if the drum shear 103 is at a standstill. This device 100 will now be explained in detail with regard to its mode of operation and the associated components.

[0038] The device comprises at least one guard device 105 (see FIG. 2), which extends at least over the entire width of the roll strip 101 (see FIG. 1) and is movably guided between the lateral stand frames 104 of the drum shear 103 by means of a guide device 106. In detail, the guide device 106 comprises four sliding guides 108.1-108.4 (see FIG. 7), each of which is attached to an inner side of the stand frames 104. The perspective view of FIG. 5 illustrates that, in one surface of a sliding guide 108.1-108.4, a first arc-shaped guide track 109.1 and a second arc-shaped guide track 109.2 are formed, wherein such guide tracks 109.1, 109.2 partially overlap.

[0039] The guard device 105 is designed in two parts and comprises two shielding elements 110, one of which is shown in perspective in FIG. 6. A shielding element 110 comprises a trough area 111 and a wall area 112. In a cross-section along the width of the roll strip 101, the wall area 112 is arranged at an angle relative to the trough area 111. The significance of such angled arrangement of the wall area 112 relative to the trough area 111 is explained separately below.

[0040] Guide pins 113 adjacent to both the trough area 111 and the wall area 112 are attached on the side edges 115 of the shielding element 110. When a shielding element 110 is mounted on two guide tracks arranged opposite one another, such guide pins 113 are brought into engagement with the aforementioned guide tracks 109.1, 109.2, which are formed in a respective sliding guide 108.1-108.4. Accordingly, a shielding element 110 can be swiveled along these guide tracks 109.1, 109.2, which is explained below.

[0041] FIG. 7 shows the device 100 with its essential functional elements in perspective, for simplification without the drum shear 103. A shielding element 110 is arranged between the opposite sliding guides 108.1, 108.2—on the left in the picture area—wherein the lateral guide pins 113 of the shielding element 110 are in engagement with the guide tracks 109.1, 109.2 of the respective sliding guides 108.1, 108.2. In combination with the drum shear of FIG. 1, the sliding guides 108.1 and 108.2 are each provided in the inlet area of the drum shear 103, that is, in the picture area of FIG. 1, each to the left of the upper knife drum 102.1. In the same manner, between the opposite sliding guides 108.3, 108.4—in the picture area of FIG. 7 and FIG. 1, each on the right—an additional shielding element 110 is arranged, the lateral guide pins 113 of which also engage in the guide tracks 109.1, 109.2 of the sliding guides 108.3, 108.4.

[0042] FIG. 7 illustrates the modular design of the device 100 in accordance with the invention. On the basis of this, it is possible to retrofit an existing drum shear 103, as shown for example in FIGS. 1 and 11, with the device 100 in accordance with the invention, wherein the knife drums 102.1, 102.2 do not require any modification. With regard to the sliding guides 108.1-108.4, it should be noted that these can be suitably attached to the inner sides of the stand frames 104 of the drum shear 103, if applicable also by means of retrofitting.

[0043] A combination of FIG. 7 with FIG. 1 (for example) makes it clear that the guard device 105 or its shielding elements 110 is/are wider than the roll strip 101.

[0044] The invention now functions as follows:

[0045] If the drum shear 103 is at a standstill and correspondingly its knife drums 102.1, 102.2. do not rotate, the shielding elements 110 are swiveled along the guide tracks 109.1, 109.2 of the respective sliding guides 108.1-108.4 into a cooling position. This corresponds to the illustration of the shielding elements 110 in FIG. 7, and also to the end face view of FIG. 8, which shows a sectional view along the line A-A of FIG. 2. Corresponding to this cooling position, the display of FIG. 8 is labeled “[K]”. For the further illustration of this cooling position, reference is also made to the perspective view in FIG. 3, which also shows a sectional view along line A-A of FIG. 2.

[0046] With regard to the cooling position [K], it should be understood that the shielding elements 110 are positioned between the upper knife drum 102.1 and the roll strip 101. Thus, the lower side of the upper knife drum 102.1 is shielded from the roll strip 101 by the two shielding elements 110, such that heat radiation from the roll strip 101 cannot directly affect the lower side of the upper knife drum 102.1.

[0047] The device 100 also includes a coolant supply device 114 in the form of spray bars arranged between the stand frames 104 of the drum shear 103 (see FIG. 1). From such spray bars 114, if the shielding elements 110 are swiveled into the cooling position, cooling water is sprayed against the inner surfaces of the wall areas 112, wherein the cooling water then arrives in the trough areas 111 of the shielding elements 110 at a reduced flow rate. In this respect, the wall areas 112 each act as a “baffle plate” in order to introduce the cooling water sprayed by the spray bars 114 with a calmed flow into the trough areas 111 of the shielding elements 110. For this purpose, the wall areas 112 are also arranged at an angle relative to the trough areas 111, as has already been explained in connection with FIG. 7.

[0048] The trough areas 111 can—in accordance with their designation—hold a certain volume of cooling water. Thus, the two shielding elements 110 are cooled and heat up less due to the heat radiation emitted by the roll strip 101. Indirectly, this also means that the upper knife drum 102.1 heats up less when the drum shear 103 is at a standstill.

[0049] As shown by the illustration of FIG. 6, on the side edges 115 of the shielding elements 110, adjacent to the trough area 111, outflow openings 116 are formed in each case, for example in the form of depressions on the edge of the trough area. In addition and/or as an alternative to this, it may be provided that the trough area 111 is penetrated by bores adjacent to the side edges 115. In any event, the effect of such outflow openings 116 or bores is that—after the trough area 111 has been completely “flooded” with cooling water—the cooling water can then escape from the side of the trough areas 111 and fall down past the side of the roll strip 101 and is disposed of in a suitable manner, for example through a scrap chute (not shown). Accordingly, if the shielding elements 110 are in the cooling position, cooling water is introduced or fed in a permanent or circulating manner into the trough areas 111 of the shielding elements 110 by means of a discharge through the spray bars 114, and then flows away downwards through the outflow openings 116, specifically laterally past the roll strip 101. This flow or falling down of the cooling water laterally past the roll strip 101 is ensured by the fact that the shielding elements 110 are each wider than the roll strip 101.

[0050] Before the drum shear 103 is set “in action” to cut through the roll strip 101, the shielding elements 110 are transferred from the cooling position [K] (see, for example, FIG. 8) to a so-called “cutting position,” which is shown, for example, in the illustration in FIG. 10, and is accordingly labeled [S]. When moving from the cooling position [K] to the cutting position [S], the shielding elements 110 with their guide pins 113 are moved or swiveled along a path curve that is defined by the arc-shaped guide tracks 109.1, 109.2 of the respective sliding guides 108.1-108.4. The course of such a swiveling from the cooling position [K] to the cutting position [S], or vice versa, is shown in the illustration in FIG. 9, which is accordingly labeled “[K-S]”.

[0051] The swiveling of the guard device 105 and its shielding elements 110 between the cooling position [K] and the cutting position [S] is achieved by suitable drive means, for example by hydraulic cylinders (not shown) that are arranged on the inlet side and on the outlet side of the drum shear 103 and that are each in operative connection with the shielding elements 110. In conjunction with such hydraulic cylinders, multiple jointed mechanisms can also be used to control the shielding elements 110. The actuation of such hydraulic cylinders, and also the supply of cooling water to the spray bars 114, can be controlled by a control device 117, which is simplified in FIG. 1 by a rectangle “117”.

[0052] Given the fact that the path curve defined by the respective arc-shaped guide track 109.1, 109.2 on the inlet side and outlet side of the drum shear 103 points convexly outwards, that is, away from the upper knife drum 102.1, in relation to the adjacent upper knife drum 102.1 (see FIG. 5), it is ensured that, when the shielding elements 110 are swiveled in the direction of the cutting position [S], the knife circle MK (see FIG. 8-10) of the upper knife drum 102.1 is not touched, and that there is no contact between the shielding elements 110 and the upper knife drum 102.1. It follows from this that at no time will there be a collision or contact between the shielding elements 110 and the upper knife drum 102.1 adjacent to them. A constantly sufficient distance between the shielding elements 110 during a move/swivel between the cooling position [K] and the cutting position [S] is also ensured by the angled arrangement of the wall area 112 relative to the trough area 111. The field of movement of the knife drum is not affected during cutting.

[0053] As soon as the shielding elements 110 have reached the cutting position, as shown in FIG. 10 and also in the perspective view of FIG. 4 (=sectional view line A-A of FIG. 2), the knife drums 102.1, 102.2 of the drum shear 103 can be set in rotation in order to cut the roll strip 101. In this respect, it is additionally pointed out that the shielding elements 110 have a sufficient distance from the roll strip 101 in the cutting position and are thus protected from any pieces of the cut roll strip 101 flying around in an uncontrolled manner.

[0054] It is understood that the supply of cooling water, which in the cooling position is spread by the spray bars 114 (as explained) and fed into the trough areas 111 of the shielding elements 110, is stopped before the shielding elements 110 are swiveled from the cooling position [K] to the cutting position [S]. The shielding elements 110 are only swiveled out of the cooling position [K] and moved away from each other after all the cooling water from the trough areas 111 has been discharged downwards through the outflow openings 116, laterally past the roll strip 101. This prevents cooling water from arriving in the roll strip 101 when the shielding elements 110 are swiveled to the cutting position [S].

[0055] After completion of a cutting operation, if the rolling process for the roll strip 101 is continued in the usual manner and the drum shear 103 is brought to a standstill again, the shielding elements 110 are swiveled from the cutting position [S] back to the cooling position [K], in accordance with a sequence of FIG. 10, FIG. 9 and FIG. 8. After the shielding elements 110 have reached the cooling position [K], cooling water is again sprayed through the spray bars 114, such that the cooling water arrives in the trough areas 111.

[0056] The device described above is particularly suitable for cooling the upper knife drum 102.1 of a drum shear 103, if a total of three knives M (see FIG. 8-FIG. 10) are attached to it.

[0057] As already explained elsewhere, optional cooling or shielding of the lower knife drum 102.2 is also possible by inserting an additional (not shown) guard device into the space between the roll strip 101 and the lower knife drum 102.2 when the drum shear 103 is at a standstill. Such an additional guard device for shielding the lower knife drum 102.2 can also be designed in the form of two separate shielding elements, which are movably guided along the guide tracks formed in a respective sliding guide (see lower area of FIG. 5: indicated there by the arrow “U”) and thus—in the same manner as the shielding elements 110 for the upper knife drum 102.1—can be swiveled on a path curve between the cooling position and the cutting position.

[0058] In addition to the design shown in the drawing, it is also possible to use the device 100 in accordance with the invention with a drum shear that is only equipped with two knives per knife drum.

[0059] Similarly, the invention can also be applied to other cross-cutting shears, for example gate shears, crank shears, etc.

LIST OF REFERENCE SIGNS

[0060] 100 Device [0061] 101 Roll strip [0062] 102.1/102.2 Upper/lower knife drum as knife-bearing element [0063] 103 Drum shear [0064] 104 Stand frame (of the drum shear 103) [0065] 105 Guard device [0066] 106 Guide device [0067] 108.1-108.4 Sliding guide(s) [0068] 109.1 First arched guide track [0069] 109.2 Second arc-shaped guide track [0070] 110 Shielding element(s) [0071] 111 Trough area (of a shielding element 110) [0072] 112 Wall area (of a shielding element 110) [0073] 113 Guide pin [0074] 114 Coolant supply device/spray bar [0075] 115 Side edge (of a shielding element 110) [0076] 116 Outlet opening (on or in a trough area 111) [0077] 117 Control device [0078] [K] Cooling position [0079] [K-S] Transition from cooling position to cutting position, and vice versa [0080] M Knife [0081] MK Field of movement/knife circle (of a knife drum 102.1, 102.2), [0082] [S] Cut position [0083] T Transport direction of the roll strip 101/direction of strip travel