Mold
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- CUNOVA GMBH
- Filing Date
- 2026-01-09
- Publication Date
- 2026-07-30
Smart Images
Figure DE2026100012_30072026_PF_FP_ABST
Abstract
Description
[0001] 09.01.2026 XG / East
[0002] Our reference number: KME520WO
[0003] cunova GmbH
[0004] Klosterstraße 29, D-49074 Osnabrück
[0005] mold
[0006] The invention relates to a mold with the features of claim 1.
[0007] DE 10 2023 112 607 B3 discloses a mold for continuous casting of metals. A mold plate is attached to a support structure via screw bolts, with a T-nut being inserted into an undercut area of a coolant channel in the mold body to be screwed to the bolt. With the T-nut in place, a cooling gap is present in the undercut area of the coolant channel, which improves the cooling of the mold plate even below the fastener. The thermal stress in this area is reduced.
[0008] US 5513691 A discloses a T-nut with a groove intended to increase the cooling gap; however, the depth of the groove is limited because the T-nut must accommodate the bolt. DE 23 24 481 A1 discloses another design of a continuous casting mold with support plates, wherein bolts extend through the support plates, and nuts are screwed onto the bolts on the outside of the support plates.
[0009] The invention is based on the objective of improving the cooling in the area of the mounting points of a mold for continuous casting of metals.
[0010] This problem is solved in a mold with the features of claim 1.
[0011] The dependent claims relate to advantageous further developments of the invention.
[0012] The mold according to the invention for continuous casting of metals has a mold body in the form of a mold tube or mold plate made of copper or a copper alloy. The mold body is attached to a support structure via connecting elements. Screw connections are used, each comprising a screw and a nut. The screw has a shank and a head that is wider than the shank. According to the invention, the head is inserted into an undercut area of a cooling water channel in the mold body with an insertion direction that is parallel to the cooling water channel, i.e., runs longitudinally along the cooling water channel and not transversely to it. The shank protrudes from the undercut area and extends towards the support structure. The nut is screwed onto the shank to connect the mold body to the support structure.
[0013] A cooling water gap remains between the upper surface of the head, facing away from the shaft, and the mold body. At least one groove extending towards the cooling water channel is arranged in the upper surface of the head. The embodiment according to the invention therefore no longer provides for a T-nut being inserted into the undercut area of the mold body, but rather the head of a screw. Due to its widened head, it can also be referred to as a T-nut screw. Its cross-section is optimized to enlarge the remaining cooling water gap and improve flow characteristics. The reverse arrangement, which is not according to the invention and involves screwing a bolt into the T-nut, requires that a minimum screw-in depth is not undercut. The T-nut must have a sufficient thread length to ensure the necessary load-bearing capacity of the connection.The head must be thick enough. Furthermore, the shank must be screwed deeply enough into the head. The optimization potential in the area of T-nuts with threaded receptacles is therefore limited. The invention solves this problem by using screws designed as T-nut screws instead of T-nuts. The threaded connection is no longer located in the undercut area, but outside of it. This allows the head to be smaller and flatter, and in particular, to have at least one groove running towards the cooling water channel. The groove, in the sense of a channel-shaped, concave depression or groove, increases the cross-section through which cooling water can flow between the top of the head and the mold body.
[0014] The invention achieves more uniform and improved cooling of the mold and the metal strand produced by continuous casting because hotspots are significantly less pronounced or avoided altogether, thus reducing the risk of uneven cooling of the solidifying metal strand. The danger of uneven cooling and the resulting stresses, deformations, and cracks in the strand shell is mitigated. Product quality is improved. The mold's service life is extended because the risk of metal damage due to overheating and diffusion of copper-damaging trace elements is reduced.
[0015] The head has edge surfaces. In particular, the head has a rectangular cross-section with steps. With this head shape, the screw cannot rotate in its installed position. At least the edge surfaces of the head oriented perpendicular to the direction of the cooling water channel have chamfers to direct cooling water to the top and into at least one groove. The chamfers reduce the dynamic pressure and have a positive effect on the flow velocity in the head area. This flow-optimized edge modification allows the cooling water to enter the cooling water gap more easily. The edge modification is particularly easy to manufacture if the chamfer is designed as a flat inclined surface. The chamfer also fulfills the flow optimization requirements if it is wholly or partially rounded, especially convexly curved. In particular, a transition area between the chamfer and the top surface can be rounded.
[0016] The chamfers are not merely small bevels or radii, but are distinctly pronounced. Each chamfer reduces the edge or top surface by 2 to 8 mm. The angle of the chamfer is preferably in the range of 20 to 60 degrees, particularly 25 to 45°, and is preferably 30°. The reference plane for the angle measurement is the top surface of the head. For non-planar chamfers, especially those that are wholly or partially rounded, the angle is measured between the top surface and the mean slope of the chamfer. The mean slope is a secant line between the starting point and an end point of the chamfer. For wholly or partially rounded chamfers, the maximum or minimum slope can deviate significantly from the mean slope (0 to 90°).
[0017] The head can have chamfers all around, i.e., on all edges. For a rectangular head, this means that even the edges oriented essentially parallel to the direction of the cooling water channel have chamfers. The angles, dimensions, and shapes of the chamfers on the longitudinally and transversely oriented edges can differ because they serve different functions. "All around" can also mean that chamfers are arranged in the transition area between adjacent edges. The entire geometry of the head is optimized to avoid hotspots in the area of the joints, to maximize the cross-sectional areas through which cooling water can flow freely, and to improve the flow. The chamfers should therefore be large enough that the edges of the head are, if necessary, completely chamfered or formed by chamfers. This applies particularly to the edges facing the coolant flow.
[0018] The undercut area of the cooling water channel is bounded by undercut clamping ribs. These clamping ribs are necessary to enable the head to exert the required clamping force on the mold body. The chamfers on the edge of the head preferably extend at least to the plane in which the undercut clamping ribs lie and, in particular, project beyond this plane in the direction of the shaft. This applies especially in the area of the at least one groove. That is, the chamfers can extend at least in the area of the groove to the undercut clamping ribs and, adjacent to the groove, only approximately to the undercut clamping ribs. From a manufacturing perspective, it is advantageous to provide geometrically uniform chamfers with the same angle of inclination around the transition area between the edge surfaces and the top surface.Since at least one groove has a certain depth, the chamfers in the area of the deepest part of the groove can extend to the undercut clamping ribs, while the chamfers outside the deepest part of the groove end before that.
[0019] In an advantageous embodiment of the invention, the head has a thickness, measured in the direction of the shank, between its upper surface and its contact surface, which surrounds the shank and rests against the mold body or the undercut clamping ribs. The at least one groove preferably has a depth of 30 to 60% of the thickness of the head. Preferably, the depth is in the range of 35 to 50%. The contact surface is located against the clamping ribs in the mounting position. The plane in which the contact surfaces are located is simultaneously the plane to which the chamfers in the region of the deepest part of the groove ideally extend at least [amount missing in original text].
[0020] The geometry of the groove and / or head is designed to withstand the mechanical loads required to secure the mold plate and is also optimized for the cooling effect of the mold plate. A groove with the largest possible cross-section is desired to achieve optimal cooling in this area. However, the width and depth of the groove are mechanically limited because the head must reliably transfer the axial force of the screw to the clamping ribs. The head has a width measured perpendicular to the cooling water channel, with the groove width of at least one groove, or the sum of the groove widths of several grooves, ranging from 40% to 70%, and specifically from 45% to 55%, of the head width. This applies particularly to a single groove. While multiple grooves would increase the surface area of the top surface and thus potentially...The cooling effect on the head is improved; however, the invention focuses not on cooling the head itself, but rather on cooling the mold body. This cooling effect is significantly improved by increasing the cross-sectional area through which the flow passes below the head. In an advantageous embodiment of the invention, a single groove is arranged centrally in the upper surface. Centrally located means extending in the longitudinal direction of the cooling channel and intersecting the longitudinal axis of the shaft perpendicularly. The cross-sectional area of the groove should be as large as possible and minimize the cross-sectional area of the end faces of the head oriented transversely to the direction of the cooling water channel. Preferably, the cross-sectional area of the groove is 15 to 30% of the cross-sectional area of the end faces oriented transversely to the direction of the cooling water. In the area of the chamfers, the ratio of the cross-sectional areas is greater.
[0021] The cross-sectional area of the groove, i.e., the groove profile, can be essentially rectangular or circular segment-shaped. It can also be a rectangular area with rounded corners for stress optimization. The groove width can be, in particular, 70 to 90% of the shaft width.
[0022] The invention is explained in more detail below with reference to the exemplary embodiments shown schematically in Figures 1 to 7. Figures 1 to 7 show:
[0023] Figure 1 shows a cross-section through the mounting area of a mold;
[0024] Figure 2 shows a longitudinal section through the attachment point of Figure 1;
[0025] Figure 3 shows a perspective view of a screw for fastening a mold plate;
[0026] Figure 4 shows the screw of Figure 3 in a side view with a detail magnification;
[0027] Figure 5 shows the screw of Figure 3 in a second side view;
[0028] Figure 6 shows the screw of Figure 3 in a longitudinal view of the screw shaft and Figure 7 shows a perspective view of a screw for fastening a mold plate in a second embodiment.
[0029] Figure 1 shows a section of a mold 1 for continuous casting of metals with a mold body 2, for example in the form of a mold tube or a mold plate, for attaching a support structure 3 via screw connections 4.
[0030] The supporting structure 3 can be made of a steel material or of a CuAl bronze with similar physical material properties to steel. The mold body 2 is made of a copper material.
[0031] The screw connection 4 comprises a screw 5 and a nut 6. The screw 5 has a shank 7 and a head 8 that is wider than the shank 7. The shank 7 passes through a spacer sleeve 9 with a radially outwardly projecting collar 10. Two locking elements 11, arranged one above the other, follow the collar 10 to prevent the nut 6 resting on it from rotating. The nut 6 exerts a clamping force on the collar 10 via the locking elements 11, thereby clamping the spacer sleeve 9 to the mold body 2. The end of the spacer sleeve 9 facing away from the collar 10 rests on clamping ribs 17, 18 on the mold body 2, while the collar 10 engages behind the support structure 3 on the side facing away from the mold body 2.
[0032] The head 8 is also supported on the mold body 2 on the side of the clamping ribs 17, 18 opposite the spacer sleeve 9. The head 8 engages in an undercut area 12 of a cooling water channel 13. It was inserted into the undercut area 12 in an insertion direction P (Figure 2) in the longitudinal direction of the cooling water channel 13 in order to engage behind the clamping ribs 17, 18.
[0033] Several cooling water channels 13, 14, 15 are formed in a rear surface 16 of the mold body 2. Cooling water is conveyed through the cooling water channels 13, 14, 15 at high flow velocity to cool the mold body 2. The head 8 in the cooling water channel 13 is also cooled. In this embodiment, the screw 5 is designed as a T-slot nut screw, with the head 8 having a special shape intended to improve the cooling effect in the area of the head 8.
[0034] Figure 3 shows an enlarged view of the screw 5 with the shaft 7 and the head 8. The head 8 is essentially rectangular. Its opposite end faces 24, 26 (Figure 6), which are oriented longitudinally along the cooling water channel 13 in the installed position, each have stepped widths adapted to clamping lugs 17, 18 (Figure 1). These lugs are engaged by the wider sections of the head 8 in the installed position. In Figure 3, the head 8 has a top surface 19 facing away from the viewer, located at the bottom of the image plane. Opposite the top surface 19, the head has contact surfaces 20 arranged on both sides and along its length, which engage the clamping lugs 17, 18. The clamping lugs 17, 18 are, in effect, clamped between the contact surfaces 20 and the spacer sleeve 9.The length of the spacer sleeve 9 allows for a certain amount of play, on the order of a few tenths of a millimeter, between the mold body 2 and the support structure 3 to compensate for thermal expansion. This also allows the mold body to shift slightly parallel to the support structure. According to the invention, the head 8 is the section of the screw 5 that engages the clamping lugs 17, 18. All other sections belong to the shank 7. The shank 7 has sections with different functions. It has a threaded section for connection to the nut 6. Optionally (Figures 1 and 2), a conically widened transition section and a cylindrical section adjoin the threaded section. The conical transition section and the cylindrical section are located in the spacer sleeve 9 when installed.The cylindrical section is followed by a section 29, located between the clamping ribs 17, 18 and extending to the mounting sides 20. This rectangular section 29 has side walls 30, 31 that run parallel to the clamping ribs 17, 18. Viewed in the flow direction S, the rectangular section 29 is exactly as long as the head 8 and has a width that is less than the distance between the clamping ribs 17, 18. The head 8 has a groove 21 in its upper surface 19. The groove 21 runs longitudinally along the head 8, i.e., in the flow direction S (Figure 2), in the cooling water channel 13. In the illustration of Figure 2, the flow is shown only through the groove 21. Of course, the other sections of the cooling water channel 13, and in particular a cooling water gap under the upper surface 19 of the head 8, are also permeated by cooling water.A bypass flow of cooling water is directed through pockets in the area of the support structure, cooling the shaft of the spacer sleeve 9 located in the pockets. In addition, the clamping webs 17, 18 are cooled from all sides, except in the contact area with the screw 5 and the spacer sleeve 9.
[0035] Another feature is the chamfers 22 on the head 8, as shown in detail in Figure 4. The chamfers 22 are inclined surfaces with an angle W1 of 30° relative to the top surface 19. The chamfers are not merely chamfers for breaking the edges, but are specifically designed to direct cooling water to the top surface 19 of the head 8. They are guide surfaces for the cooling water.
[0036] The chamfers 22 are located at the edge of the head 8 in the entire inflow area and especially in the area of the centrally arranged groove 21. Due to the large dimensions of the chamfers 22, they extend to a plane in which the contact surfaces 20 abutting the mold body are located, i.e., vertically up to the clamping ribs 17, 18 (Figures 1 to 3) or up to the rectangular area 29 of the shaft 7. The advantage is that the inflowing cooling water is directed in a controlled and funnel-shaped manner into the groove 21 and under the top of the head 8. The funnel shape results from the chamfers 22 in conjunction with the cross-section of the coolant channel 13.
[0037] Figures 3 to 6 show that all edge faces 23 to 26 have the aforementioned chamfers at the transition to the common upper surface 19 with the groove 21. For the sake of simplicity, reference numeral 22 is used for all chamfers. The angle W1 of the chamfer is 30° to the upper surface 19 in all cases. The head 8, and thus the screw 5, can be rotated by 180° because the inflow and outflow ends of the head 5 are identical. The central groove 21 is relatively large. Its lateral flanks are rounded with a radius R. The groove 21 therefore has a substantially rectangular cross-section with a flat groove base and completely rounded side walls. The head 8 has a width B1 perpendicular to the orientation of the groove 21, with a width B2 of the groove 21 being between 40 and 50% of the width B1 of the head 8.
[0038] The depth T of the groove 21, measured in the longitudinal direction of the shaft 7, is approximately 40% of the thickness D of the head 8. The thickness D of the head 8 is measured between its contact sides 20 and its upper surface 19 adjacent to the groove 21.
[0039] Figure 5 shows that the cross-sectional area through which the groove 21 flows occupies a significant proportion of the area of the edge 23 exposed to the flow. The cross-sectional area through which the groove flows can comprise 15 to 30% of the cross-sectional area of the edge 23 up to the height of the mounting side 20. In this embodiment, the angle W3 of the chamfer between the top surface 19 and the edge 24, which runs parallel to the flow direction S, is also 30°.
[0040] Figure 6 also shows that the corner regions 32 between adjacent edge faces 23-26 are also provided with chamfers 27 to direct cooling water laterally past the head 8, with the aim of improving the cooling effect on the head 8 and the mold body 2. The angle W2 of the chamfer can also be 30° here. The chamfers themselves can begin at a distance of, for example, 2 to 5 mm from the corner region and are therefore of a considerable size. The chamfers 22 in the region of the groove 21, i.e., in the transition to the upper surface 19, can be somewhat larger than the chamfers 27 in the corner region, since the flow is to be directed mainly towards the groove 21.
[0041] Figure 7 shows another embodiment of a screw 5. The reference numerals already introduced are used. The difference from the screw 5 of the first embodiment is that the chamfer 22 is rounded at the transition to the upper surface 19. The chamfer 22 transitions tangentially into the upper surface 19 or into the groove 21. The radius of curvature is chosen to be so large that the chamfer 22 is completely rounded, so that the curvature begins at the edge 23 and is entirely convex. The beginning of the curvature in the area of the groove 21 is even located in the direction of the shaft 7 above the bearing surfaces 20 in the widened area 29. The other chamfers of this design, which are not specified in detail, correspond to those of the first embodiment, so that rounded chamfers are combined with flat chamfers. Reference numerals:
[0042] 1 - Mold
[0043] 2 - Mold body
[0044] 3 - Supporting structure
[0045] 4 - Screw connection
[0046] 5 - screw of 4
[0047] 6 - Nut of 4 7 - Shaft of 5
[0048] 8 - Head of 5
[0049] 9 - Spacer sleeve
[0050] 10 - Collar of 9
[0051] 11 - Safety element
[0052] 12 - undercut area 13 - cooling water channel
[0053] 14 - Cooling water channel
[0054] 15 - Cooling water channel
[0055] 16 - Back of 2
[0056] 17 - Clamping bridge
[0057] 18 - Clamping bridge
[0058] 19 - Top of 8
[0059] 20 - Investment page of 8
[0060] 21 - groove in 19
[0061] 22 - Bevel
[0062] 23 - Edge of 8
[0063] 24 - Edge of 8
[0064] 25 - Edge of 8
[0065] 26 - Edge of 8
[0066] 27 - Bevel
[0067] 28 - Cooling water gap below 19 29 - rectangular area 30 - side wall of 29
[0068] 31 - Side wall of 2932 - Corner area
[0069] B1 - Width of 8
[0070] B2 - Width of 21
[0071] D - Thickness of 8
[0072] P - insertion direction from 5 R - radius at 21
[0073] S - Flow direction
[0074] T - Depth of 21
[0075] W1 - Angle
[0076] W2 - Angle
[0077] W3 angle
Claims
Patent claims 1. Mold (1) for continuous casting of metals with a mold body (2) in the form of a mold tube or a mold plate for attachment to a support structure (3) via screw connections (4), wherein the screw connections (4) each have a screw (5) and a screw nut (6), wherein the screw (5) has a shank (7) and a head (8) wider than the shank (7), characterized in that the head (8) is inserted into an undercut area (12) of a cooling water channel (13) of the mold body (2), with an insertion direction (P) parallel to the cooling water channel (13), wherein the shank (7) projects out of the undercut area (12) and extends to the screw nut (6) on the support structure (3), wherein a cooling water gap (28) is formed between a top surface (19) of the head (8) facing away from the shank (7) and the mold body (2). cooling water channel (13) remains,wherein at least one groove (21) extending in the direction of the cooling water channel (13) is arranged in the upper surface (19) of the head (8).
2. Mold (1) according to claim 1, characterized in that the head (8) has edge sides (23-26) wherein chamfers (22) are arranged on the edge sides (23, 25) oriented at least transversely to the direction of the cooling water channel (13) in order to direct cooling water to the top (19) and into the at least one groove (21).
3. Mold (1) according to claim 2, characterized in that the head (8) has chamfers (22) between its upper surface (19) and all edge sides (23-26).
4. Mold (1) according to any one of claims 1 to 3, characterized in that the head (8) has a thickness (D) measured in the direction of the shaft (7) between its upper surface (19) and its contact surface (20) abutting the mold body (2), wherein the at least one groove (21) has a depth (T) that is 30 to 60% of the thickness (D) of the head (8).
5. Mold (1) according to any one of claims 2 to 4, characterized in that the undercut area (12) is bounded by undercut clamping ribs (17, 18), wherein the chamfers (22) on the edge side of the head (8) in the area of the at least one groove (21) extend at least to a plane in which the contact surfaces (20) abutting the mold body are located.
6. Mold (1) according to one of claims 1 to 5, characterized in that the head (8) has a width (B1) measured transversely to the cooling water channel (13), wherein the groove width (B2) of the at least one groove (21) or the sum of the groove widths of several grooves is in a range of 40 to 70% of the width (B1) of the head (8).
7. Mold (1) according to one of claims 1 to 6, characterized in that a single central groove (21) is arranged in the top surface (19), wherein a cross-sectional area of the groove (21) is 15 to 30% of the cross-sectional area of the edge sides (23, 25) oriented transversely to the direction of the cooling water channel (13).
8. Mold (1) according to one of claims 1 to 7, characterized in that the shaft (7) passes through a spacer sleeve (9) with a radially outwardly projecting collar (10), wherein the screw nut (6) exerts a clamping force on the collar (10) and clamps the spacer sleeve (9) to the mold body (2).
9. Mold (1) according to one of claims 2 to 8, characterized in that corner areas (32) of the head (8) between adjacent edge sides (23-26) are provided with chamfers (27).