Continuous casting machine crystallizer and continuous casting machine

Abstract

The invention provides a continuous casting machine crystallizer and a continuous casting machine. The continuous casting machine crystallizer comprises a copper pipe and a water jacket, the water jacket is connected to the periphery of the copper pipe in a sleeved mode, a plurality of grooves longitudinally extending along the copper pipe are formed in the outer wall of the copper pipe, the water jacket is composed of a base body layer and a soft layer, the soft layer is tightly connected with the inner wall of the base body layer, the soft layer is made of flexible materials, and the material hardness of the soft layer is smaller than that of the copper pipe. The problem that components such as the copper pipe are damaged during assembly can be avoided, preferably, no gap exists between the inner wall of the soft layer and the outer wall of the copper pipe, the cooling efficiency and the cooling uniformity can be improved, and the assembly difficulty and the assembly cost are reduced.

Description

Technical Field

[0001] The invention belongs to the fields of mechanical technology and iron and steel metallurgy technology, and in particular relates to a continuous casting machine crystallizer and a continuous casting machine. Background Art

[0002] In the metal solidification production of polygonal cross-section ingots such as round, square and rectangular, the liquid metal is poured into the crystallizer and cooled once in the crystallizer, or after once cooling, it is cooled twice out of the crystallizer to form a metal ingot. The tubular crystallizer is usually composed of a tubular body, a water jacket and a cylinder. The tubular body is usually made of copper or copper alloy, generally referred to as a "copper tube". The molten metal is poured into the copper tube of the crystallizer, and the outside of the copper tube of the crystallizer is cooled by a cooling medium (such as water), so that the molten metal in the inner cavity of the copper tube crystallizes and solidifies along the inner wall of the copper tube to form a quenching layer, and then a primary ingot shell with a certain safety thickness is formed before the metal ingot with a liquid core leaves the copper tube of the crystallizer.

[0003] The efficient continuous casting process requires uniform and efficient cooling of the crystallizer and uniform growth of the primary shell. At present, the more common cooling method is to process multiple longitudinal grooves on the outer wall of the copper tube, and set a water jacket outside the copper tube. The water jacket and the grooves form a channel of a certain width for the cooling medium to pass through. In order to obtain a uniform primary shell, the first task is to ensure that the cooling medium passes through these channels, so the gap between the inner wall of the water jacket and the outer wall of the copper tube should be as small as possible, and the ideal state is to be close together. If the gap is too large, the cooling water will flow through the gap, which will inevitably affect the amount of cooling water flowing through the channel, thereby reducing the cooling efficiency; and if the gap is too large, it is difficult to ensure uniform gaps around the crystallizer during assembly. It is easy for the gap to shift to one side, forming a situation where one side is close and the other side is doubled, so that the amount of cooling water around the outer wall of the copper tube is quite different, resulting in uneven cooling, affecting the uniformity of shell solidification, and ultimately leading to quality accidents. Especially when the flow rate and pressure of the cooling medium of the crystallizer for efficient continuous casting are high, for example, the efficient continuous casting of 165mm×165mm square billet requires the crystallizer cooling water supply pressure to be 1.0MPa-1.2MPa and the water volume to be 180m 3 -200m 3 (More than 50% more than conventional continuous casting). Under such conditions, the gap between the outer wall of the copper tube and the inner wall of the water jacket is too large or uneven, which makes it easier to cause uneven cooling and heat transfer around the copper tube, thus seriously affecting the stability of continuous casting production.

[0004] However, on the other hand, in order to facilitate assembly, there needs to be a certain gap between the outer diameter of the copper tube and the inner diameter of the water jacket. This is because in actual production, there is often a design tolerance between the outer diameter of the copper tube and the inner diameter of the water jacket. For example, in a traditional water jacket crystallizer, the design tolerance requirement for the outer wall of the copper tube and the inner wall of the water jacket is ±0.2mm, and due to production process reasons, this tolerance requirement is often difficult to achieve. Therefore, in order to avoid the copper tube from not being able to fit into the water jacket, the gap between the outer diameter of the copper tube and the inner diameter of the water jacket is at least 0.5mm. Therefore, it is difficult to achieve the ideal state of the inner wall of the water jacket and the outer wall of the copper tube being close together. Therefore, when the copper tube, water jacket and other components are replaced (the copper tube is a consumable part in the continuous casting crystallizer and needs to be frequently disassembled and replaced), it is often necessary to adjust the gap to be evenly distributed around. This will inevitably require the disassembly of other components in the crystallizer for gap adjustment operations. In severe cases, it is even necessary to disassemble the water jacket and the copper tube for pre-assembly, resulting in assembly difficulties and a large workload. In addition, during the assembly process, the copper tube is prone to collision with the water jacket. If the water jacket is made of hard materials, there are risks such as wear of the steel tube. Summary of the invention

[0005] In view of the above technical status, the present invention provides a continuous casting machine crystallizer, wherein the copper tubes are easy to assemble and can reduce damage to the copper tubes during assembly.

[0006] The technical solution of the present invention is: a continuous casting machine crystallizer, including a copper tube and a water jacket, the water jacket is sleeved on the outer periphery of the copper tube, and the outer wall of the copper tube is provided with a plurality of grooves extending along the longitudinal direction of the copper tube; the water jacket is composed of a base layer and a soft layer, and the soft layer is tightly connected to the inner wall of the base layer; the material of the soft layer is flexible, and the material hardness of the soft layer is less than the material hardness of the copper tube.

[0007] In the present invention, the copper tube is a tubular structure with two ends open. In the tubular structure, the extension direction of the axis of the hollow inner cavity is the longitudinal direction of the copper tube, and the section perpendicular to the axial direction of the hollow inner cavity is the cross section.

[0008] The soft layer is made of any material, including glass fiber, plastic, rubber and composite materials thereof. The soft layer contacts the copper tube, and heat is transferred to the soft layer during the heat exchange process. Preferably, the soft layer is made of a material with high temperature resistance, and preferably, the heat resistance temperature is greater than or equal to 200°C. Preferably, the soft layer is made of a material with high temperature resistance, including glass fiber, plastic, rubber and composite materials thereof.

[0009] In order to make the water jacket rigid enough to withstand the pressure difference of the cooling medium and the pressure transmitted by the deformation of the copper tube under the static pressure of the molten steel, it is preferred that the material of the base layer is a rigid material with a hardness greater than that of the soft layer. The material of the base layer includes but is not limited to rigid metal materials, such as stainless steel, carbon steel, copper and other metals.

[0010] The soft layer is on the periphery of the copper tube. In order to minimize the gap between the inner wall of the soft layer and the outer wall of the copper tube, thereby improving the cooling efficiency and cooling uniformity, preferably, in each cross section of the copper tube and the water jacket, the gap between the inner diameter of the soft layer and the outer diameter of the copper tube is not greater than 0.5 mm, and further preferably not greater than 0.2 mm. More preferably, there is no gap between the inner diameter of the soft layer and the outer diameter of the copper tube. At this time, when the copper tube is sleeved in the water jacket, the flexibility of the soft layer can guide the copper tube, and the grooves between the inner wall of the soft layer and the outer wall of the copper tube are closed to form a cooling channel along the longitudinal direction of the copper tube.

[0011] The connection method between the soft layer and the inner wall of the base layer is not limited. The soft layer can be tightly connected to the base layer by bonding, or the soft layer can be formed on the inner wall of the base layer by a high-temperature die-casting process, for example, by high-temperature one or more die-casting precision molding, or it can be roughly cast and then processed to obtain the precise inner cavity size. In order to enhance the bonding force between the base layer and the soft layer, a number of base layer pits and / or base layer protrusions can be set on the inner wall of the base layer, and a number of soft layer protrusions matching the base layer pits and soft layer pits matching the base layer protrusions can be set on the outer wall of the soft layer, that is, the base layer pits and the soft layer protrusions form a tight bond, and the base layer protrusions and the soft layer pits form a tight bond. Preferably, the height of the base layer protrusion does not exceed 2 / 3 of the thickness of the soft layer, and more preferably does not exceed 1 / 3 of the thickness of the soft layer.

[0012] The thickness of the base layer is not limited and can be adjusted according to actual needs. Preferably, the thickness of the base layer is 10 mm-20 mm.

[0013] The thickness of the soft layer is not limited and can be adjusted according to actual needs. Preferably, the thickness of the soft layer is 3 mm-6 mm.

[0014] The depth, width, spacing or number of the grooves are not limited and are designed according to actual heat transfer requirements. Preferably, one or more of the depth, width, spacing and number of the grooves are designed to form a uniform cooling effect on the outer wall of the copper tube.

[0015] The structure of the water jacket is not limited, and can be an integral structure or a split structure, for example, a split structure consisting of two parts split along the longitudinal direction, and the two parts of the water jacket are connected on the outer wall of the base, for example, by a connecting plate.

[0016] The cross-sectional shape of the copper tube is not limited and can be rectangular, circular or other shapes.

[0017] Compared with the prior art, the present invention designs the water jacket as a two-layer structure consisting of a base layer and a soft layer, and the soft layer is tightly connected to the inner wall of the base layer, which has the following beneficial effects:

[0018] (1) Due to the setting of the soft layer, the problem of damage and wear of copper tubes and other parts caused by collision and friction during assembly is avoided. When the inner diameter of the soft layer is equal to the outer diameter of the copper tube, it can guide the copper tube without scratching it. In particular, when the inner diameter of the soft layer is equal to or slightly smaller than the outer diameter of the copper tube due to manufacturing tolerance of the copper tube, making it difficult to install the copper tube, the soft layer is flexible, so it can be assembled by pressing, knocking, etc. without damaging the copper tube.

[0019] (2) The present invention preferably has no gap between the inner wall of the soft layer and the outer wall of the copper tube. On the one hand, the grooves of the inner wall of the soft layer and the outer wall of the copper tube are sealed to form a cooling channel along the longitudinal direction of the copper tube. During the cooling process, the cooling medium can be basically completely transmitted through these cooling channels, avoiding the cooling medium flowing through the gap formed between the inner wall of the water jacket and the outer wall of the copper tube and reducing the amount of cooling water flowing through the channel, thereby improving the cooling efficiency, achieving efficient cooling, and providing guarantee for uniform cooling of the outer wall of the copper tube. When the channel formed by the groove of the outer wall of the copper tube and the inner wall of the soft layer can provide a uniform cooling effect, since there is no gap between the inner wall of the soft layer and the outer wall of the copper tube, the cooling effect of each channel is guaranteed to be consistent; on the other hand, when there is a gap between the inner wall of the water jacket and the outer wall of the copper tube, the need for position alignment and other steps during installation is avoided, thereby reducing the difficulty and cost of assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the crystallizer structure in Example 1.

[0021] Figure 2 yes Figure 1 AA section view of the water jacket and copper tube.

[0022] Figure 3 yes Figure 1 Schematic diagram of the longitudinal section of the water jacket.

[0023] Figure 4 yes Figure 3 AA cross-section diagram.

[0024] Figure 1-4 The reference numerals in the drawings are:

[0025] 1-water jacket, 2-copper tube, 3-cylinder, 11-flange, 12-base layer, 13-soft layer, 21-cooling channel, 22-gap between the inner wall of the soft layer and the outer wall of the copper tube, 31-lower water cavity, 32-upper water cavity. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with embodiments.

[0027] like Figure 1As shown, the crystallizer includes a copper tube 2, a water jacket 1 and a cylinder 3, and the copper tube 2 and the water jacket 1 are arranged in the cylinder 3 ( Figure 1 Only the positional relationship between the cylinder 3 and the copper tube 2 and the water jacket 1 in the cross section is shown. In order to clearly show the copper tube and the water jacket, the longitudinal direction of the cylinder is not shown).

[0028] The water jacket 1 is sleeved on the outer periphery of the copper tube 2. Figure 2 As shown, in this embodiment, the cross section of the copper tube is a rectangle with arc chamfers, and a plurality of grooves are arranged on the outer wall of the copper tube, and there is a certain interval between each groove.

[0029] like Figure 1 , 3 As shown, in this embodiment, the water jacket 1 is composed of a flange 11, a base layer 12 and a soft layer 13. The soft layer 13 is tightly connected to the inner wall of the base layer 12. The soft layer is on the periphery of the copper tube. The flange 11 is located on the periphery of the base layer and is connected to the base layer by welding, and divides the crystallizer water chamber into an upper water chamber 32 and a lower water chamber 31.

[0030] In this embodiment, the soft layer 13 is made of high temperature resistant rubber, and the base layer 12 and the flange 11 are made of stainless steel with high rigidity and hardness.

[0031] In this embodiment, the thickness of the base layer is 10 mm-20 mm, and the thickness of the soft layer is about 3 mm-6 mm.

[0032] In this embodiment, the soft layer 13 is formed on the inner wall of the base layer 12 by one or more high-temperature die-casting precision molding processes. In some embodiments, high-temperature rough casting can be used and then processed to obtain the precise inner cavity size of the soft layer. In some embodiments, a plurality of base layer pits and / or base layer protrusions can be set on the inner wall of the base layer, and a plurality of soft layer protrusions matching the base layer pits can be set on the outer wall of the soft layer, and the two form a tight combination, and soft layer pits matching the base layer protrusions can be set, and the two form a tight combination, and the height of the base layer protrusions does not exceed 2 / 3 of the thickness of the soft layer.

[0033] In this embodiment, in the continuous casting process, liquid metal is poured into the copper tube 2 of the crystallizer, and the solidification heat exchange in the copper tube 2 is achieved by cooling the outer wall of the copper tube by cooling water. Figure 1 As shown, after the cooling water enters the lower water chamber 31 of the crystallizer, it enters the cooling channel 21 from the lower end of the copper tube, cools the outer wall of the copper tube during the bottom-up flow process, and after the cooling water temperature rises, it returns to the upper water chamber 32 of the crystallizer from the upper end of the copper tube and returns to the cooling water system.

[0034] In this embodiment, the gap 22 between the inner wall of the soft layer and the outer wall of the copper tube is substantially zero, that is, there is substantially no gap between the inner wall of the soft layer and the outer wall of the copper tube, forming a close fit, and the grooves of the inner wall of the soft layer and the outer wall of the copper tube are closed to form a cooling channel 21 along the longitudinal direction of the copper tube, and the upper and lower ends of these cooling channels 21 are open and communicated with the upper and lower water chambers of the crystallizer, and the cooling water can be completely transmitted through these cooling channels, achieving efficient cooling. In addition, in this embodiment, the depth, width, spacing, and number of the grooves on the outer wall of the copper tube 2 are designed according to the results of heat transfer calculations, and are closed with the inner wall of the soft layer to form a cooling channel 21 along the longitudinal direction of the copper tube, forming a uniform cooling effect on the liquid metal in the copper tube in the continuous casting process. In some embodiments, in each cross section of the copper tube and the water jacket, the gap between the inner diameter of the soft layer and the outer diameter of the copper tube is 0.2mm-0.5mm.

[0035] In this embodiment, when replacing the crystallizer copper tube 2, it is only necessary to remove the upper flange gland of the crystallizer cylinder 3, remove the old copper tube, replace it with a new copper tube, and then assemble the upper flange gland. Since the inner diameter of the soft layer 13 of the water jacket 1 is substantially equivalent to the outer diameter of the copper tube 2, when the copper tube 2 is inserted, the soft layer 13 guides the copper tube 2 without scratching it, and the gap between the two is extremely small, which will not cause uneven peripheral gaps between the two. At the same time, due to the use of a soft contact structure, when the copper tube is difficult to insert due to the manufacturing tolerance of the copper tube, a soft hammer can be used to knock it for auxiliary assembly without damaging the copper tube.

[0036] Finally, it should be noted that the specific embodiments described in this article are merely examples of the spirit of the present invention, and are not intended to limit the implementation methods of the present invention. Those skilled in the art of the present invention may make various modifications or supplements to the specific embodiments described, or replace them in a similar manner. It is not necessary and impossible to provide all examples of all implementation methods here. However, these obvious changes or modifications derived from the essential spirit of the present invention still fall within the scope of protection of the present invention, and interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. A continuous casting machine crystallizer, comprising a copper tube and a water jacket, wherein the water jacket is sleeved on the outer periphery of the copper tube, and the outer wall of the copper tube is provided with a plurality of grooves extending along the longitudinal direction of the copper tube; wherein: The water jacket is composed of a base layer and a soft layer, and the soft layer is tightly connected to the inner wall of the base layer; the material of the soft layer is flexible, and the hardness of the material of the soft layer is less than that of the copper tube.

2. The continuous casting machine crystallizer according to claim 1, characterized in that: The soft layer is made of glass fiber, plastic, rubber and composite materials thereof; Preferably, the constituent material of the soft layer has high temperature resistance; Preferably, the heat-resistant temperature of the constituent material of the soft layer is greater than or equal to 200°C; Preferably, the soft layer is made of high temperature resistant glass fiber, plastic, rubber and composite materials thereof.

3. The continuous casting machine crystallizer according to claim 1, characterized in that: The material of the base layer is a rigid material; Preferably, the material hardness of the base layer is greater than the material hardness of the soft layer; Preferably, the material of the base layer is a metal material; Preferably, the material of the base layer is stainless steel, carbon steel or copper.

4. The continuous casting machine crystallizer according to claim 1, characterized in that: In each cross section of the copper tube and the water jacket, the gap between the inner diameter of the soft layer and the outer diameter of the copper tube is no greater than 0.5 mm, preferably no greater than 0.2 mm.

5. The continuous casting machine crystallizer according to claim 4, characterized in that: There is no gap between the inner diameter of the soft layer and the outer diameter of the copper tube.

6. The continuous casting machine crystallizer according to claim 1, characterized in that: The soft layer is tightly connected to the base layer by bonding, or the soft layer is formed on the inner wall of the base layer by a high-temperature die-casting process.

7. The continuous casting machine crystallizer according to claim 1, characterized in that: A plurality of base layer pits and / or base layer protrusions are arranged on the inner wall of the base layer, a plurality of soft layer protrusions matching the base layer pits and soft layer pits matching the base layer protrusions are arranged on the outer wall of the soft layer, the base layer pits are tightly combined with the soft layer protrusions, and the base layer protrusions are tightly combined with the soft layer pits; Preferably, the height of the protrusions of the base layer does not exceed 2 / 3 of the thickness of the soft layer, and more preferably does not exceed 1 / 3 of the thickness of the soft layer.

8. The continuous casting machine crystallizer according to claim 1, characterized in that: The depth, width, spacing, and number of the grooves may be designed to achieve uniform cooling according to actual heat transfer requirements.

9. The continuous casting machine crystallizer according to claim 1, characterized in that: The thickness of the substrate layer is 10mm-20mm; Preferably, the soft layer has a thickness of 3 mm to 6 mm.

10. The continuous casting machine crystallizer according to claim 1, characterized in that: The water jacket is an integral structure or a split structure; Preferably, the water jacket is a split structure, consisting of two parts split along the longitudinal direction, and the two parts of the water jacket are connected at the outer wall of the base.

11. A continuous casting machine, characterized in that: A crystallizer comprising the crystallizer according to any one of claims 1 to 10.

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