Composite cushion for steel sheet stacking and steel sheet stacking method

Abstract

This invention discloses a composite pad for stacking steel plates, comprising an upper pad, a lower pad, and middle pads; both the upper and lower pads are made of copper; multiple middle pads are fixed at intervals between the upper and lower pads; adjacent middle pads, the upper pad, and the lower pad together form an air channel; stacked steel plates are placed on the upper pad. This invention also discloses a method for stacking steel plates. The beneficial effects of this invention are: This invention uses relatively soft copper material as the upper and lower pads, and uses heat-insulating and refractory material to make the middle pads. The upper surface of this composite structure is copper, allowing high-temperature steel plates to be placed directly. High-temperature steel plates after heat treatment do not need to be cooled on roller conveyors before being directly stacked. There are no restrictions on the stacking temperature of the steel plates, ensuring that the same stack of steel plates undergoes the same temperature history, resulting in more stable steel plate quality.

Description

Technical Field

[0001] This invention belongs to the field of steel cooling uniformity control technology, specifically relating to a composite pad for steel plate stacking and a steel plate stacking method, used to prevent local deformation, warping and performance instability caused by uneven cooling during the cooling process of stacked steel plates after furnace exit. Background Technology

[0002] In China, high-strength steel plates are typically delivered using controlled rolling processes or in a normalized state. For medium and heavy plates with less stringent quality requirements, a stacking cooling process is often employed to cool the steel plates. However, the proper use of stacking technology can significantly improve the ductility and impact toughness of the steel plates.

[0003] Currently, after steel plates exit the heat treatment furnace, in order to reduce the cooling rate and control the performance of the steel plates, they are usually cooled naturally by stacking. To prevent uneven heat dissipation caused by too many stacked steel plates, wooden or steel sleepers are usually used to separate the steel plates. However, both of these sleepers have problems.

[0004] When using wooden sleepers, the low ignition point of wood means that the high-temperature steel plates can easily ignite the sleepers, causing a fire. The low ignition point of the wood also limits the steel plates' cooling temperature. Therefore, when steel plates undergo high-temperature heat treatment, they must remain on the roller conveyor for a period after exiting the furnace. Only after the steel plates have cooled to a certain temperature can they be lifted off the conveyor for stacking and cooling. This results in excessively long time intervals between the steel plates leaving the production line, with stacked steel plates being mixed in hot and cold states. The heat dissipation processes affect each other, and differences in temperature history between the upper and lower layers of each stack can easily lead to differences in the steel plate's microstructure and properties, thus affecting the stability of the steel plate's quality. Furthermore, when using wooden sleepers, the low thermal conductivity of wood means that the parts of the steel plate in contact with the sleepers are in an adiabatic state, resulting in extremely slow cooling. Meanwhile, the parts not in contact with the sleepers are affected by ambient air convection, leading to faster heat dissipation. This creates vastly different heat dissipation conditions between the contact and non-contact areas, causing uneven cooling, thermal stress, and ultimately, steel plate warping.

[0005] When steel sleepers are used, the thermal conductivity of the parts where the steel plates contact the sleepers is high. The higher-temperature steel plates on top and the lower-temperature steel plates below form thermal bridges at the sleepers. The lower-temperature steel plates in contact with the sleepers are affected by the heat conduction from the top, and their cooling rate is much slower than that of other non-contact parts. This results in uneven cooling of the steel plates in certain areas, causing deformation of the steel plates. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing a composite pad for steel plate stacking and a steel plate stacking method, aiming to improve the cooling uniformity of stacked steel plates.

[0007] The technical solution adopted in this invention is: a composite pad for stacking steel plates, comprising an upper pad, a lower pad, and a middle pad block;

[0008] Both the upper and lower pads are made of copper.

[0009] The middle pad block consists of multiple blocks, which are fixed at intervals between the upper pad plate and the lower pad plate;

[0010] The two adjacent middle pads, the upper pad, and the lower pad together enclose and form an air channel;

[0011] The stacked steel plates are placed on the upper pad.

[0012] According to the above scheme, the middle pads are arranged at intervals along the horizontal and vertical directions. Among them, two adjacent middle pads in the horizontal direction form a horizontal air channel together with the upper pad and the lower pad, and two adjacent middle pads in the vertical direction form a vertical air channel together with the upper pad and the lower pad.

[0013] According to the above scheme, the centerlines of the lateral air passage and the longitudinal air passage intersect perpendicularly.

[0014] According to the above scheme, the intermediate pad block is a heat-insulating refractory brick.

[0015] According to the above scheme, the thermal conductivity of the intermediate pad is <3W / (m·℃).

[0016] According to the above scheme, the thickness of the upper pad and the lower pad is 5~10mm.

[0017] According to the above scheme, the outer side of the end pad is connected to the upper pad or the lower pad through the first fixing plate.

[0018] According to the above scheme, the inner side of the end pad and both sides of the middle pad are connected to the upper pad or the lower pad through the L-shaped second fixing plate, respectively.

[0019] The present invention also provides a method for stacking steel plates, the method being:

[0020] Prefabricate multiple composite pillows as described above;

[0021] Based on the length of the stacked steel plates, place the first layer of composite pads at intervals on the ground. The first layer of composite pads shall have at least 3 pads, with one pad at each end.

[0022] After the steel plates come off the heat treatment furnace, they are directly stacked on the first layer of composite pads.

[0023] After the steel plates on the first layer of composite pads reach the design requirements, the second layer of composite pads is placed on top of the first bundle of steel plates, with the position of the second layer of composite pads corresponding to the position of the first layer of composite pads.

[0024] The steel plates for the heat treatment furnace are stacked sequentially on the second layer of composite pads until the stack thickness of the second bundle of steel plates reaches the design requirements; the composite pads are set up and the steel plates are stacked in the same way until the overall stack height reaches the design requirements.

[0025] According to the above plan, three composite cushions are set in each layer.

[0026] The beneficial effects of this invention are as follows:

[0027] (1) The present invention uses a soft copper material as the upper pad and the lower end plate, and uses heat-insulating and fire-resistant material to make the middle pad. The upper surface of this composite structure is a copper surface, and high-temperature steel plates can be placed directly. The high-temperature steel plates after leaving the heat treatment furnace do not need to be cooled on the roller conveyor and can be directly stacked off the line. There is no limit to the stacking temperature of the steel plates, which ensures that the same stack of steel plates undergoes the same temperature experience, and the quality of the steel plates is more stable. At the same time, due to the increase in the temperature of the steel plates off the line, the temperature of the stacking area can be increased, which reduces the cooling rate of the steel plates and makes the performance of the steel plates more stable.

[0028] (2) The present invention uses a fire-resistant heat insulation material with low thermal conductivity between the upper pad and the lower pad to avoid thermal short circuit between steel plates caused by the use of steel sleepers. The steel plates of the whole block can be in the same cooling state, which can avoid the deformation and warping of the steel plates caused by excessively fast or slow local cooling caused by other methods.

[0029] (3) In this invention, several middle pads made of heat-insulating refractory bricks with low thermal conductivity are set between the upper pad and the lower pad, and the contact surface between the upper and lower steel plates is small. Since longitudinal and transverse air channels that communicate with the environment are added between the upper and lower steel plates, air can flow freely in the channels between the upper and lower steel plates, ensuring the cooling speed and cooling uniformity of the steel plates, and reducing quality defects such as bending and deformation of the steel plates. Attached Figure Description

[0030] Figure 1 This is a structural schematic diagram of a specific embodiment of the present invention.

[0031] Figure 2 for Figure 1 BB section view in the middle.

[0032] Figure 3 for Figure 1 CC section view in the image.

[0033] Figure 4 This is a schematic diagram of the working state of this embodiment.

[0034] Wherein: 1-Upper pad; 2-Lower pad; 3-Middle pad; 4-First fixing plate; 5-Second fixing plate; 6-Fixing bolt; 7-Transverse air channel; 8-Longitudinal air channel; 9-Composite pad; 10-Steel plate. Detailed Implementation

[0035] To better understand the present invention, it will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] like Figures 1-3 A composite pad 9 for stacking steel plates is shown, comprising an upper pad 1, a lower pad 2, and a middle pad 3;

[0037] Both the upper pad 1 and the lower pad 2 are made of copper.

[0038] There are multiple middle pads 3, which are fixed at intervals between the upper pad 1 and the lower pad 2;

[0039] The two adjacent middle pads 3, the upper pad 1 and the lower pad 2 together enclose and form an air channel;

[0040] The steel plate 10 is placed on the upper pad 1.

[0041] In this embodiment, the thickness of the upper pad 1 and the lower pad 2 is 5~10mm.

[0042] In this embodiment, the outer side of the end pad 3 is connected to the upper pad 1 or the lower pad 2 through the first fixing plate 4. Specifically, the first fixing plate 4 is connected to the middle pad 3 and the upper pad 1 (or the lower pad 2) through bolts 6 respectively.

[0043] In this embodiment, the inner side of the end pad 3 and both sides of the middle pad 3 are connected to the upper pad 1 or the lower pad 2 via L-shaped second fixing plates 5. Specifically, the horizontal section of the second fixing plate 5 is attached to the upper pad 1 or the lower pad 2 and connected by bolts 6, and the vertical section of the second fixing plate 5 is attached to the vertical outer wall of the middle pad 3 and connected by bolts 6.

[0044] In this embodiment, both the first fixing plate 4 and the second fixing plate 5 are made of steel with a thickness of 1~3mm.

[0045] Preferably, the middle pads 3 are arranged at intervals along the transverse and longitudinal directions, wherein two adjacent middle pads 3 in the transverse direction, together with the upper pad 1 and the lower pad 2, form a transverse air channel 7, and two adjacent middle pads 3 in the longitudinal direction, together with the upper pad 1 and the lower pad 2, form a longitudinal air channel 8.

[0046] Preferably, the intermediate pad 3 is a heat-insulating refractory brick with a thermal conductivity of <3W / (m·℃).

[0047] In this invention, there are 4 to 6 middle pad blocks 33, which are aligned and spaced apart along the horizontal and vertical directions, with a spacing of 50 to 100 mm between them; the center lines of the horizontal air channel 7 and the vertical air channel 8 intersect perpendicularly.

[0048] like Figure 3 As shown, a method for stacking steel plates is as follows:

[0049] Prefabricate multiple composite pillows as described above 9;

[0050] Based on the length of the stacked steel plate 10, the first layer of composite pads 9 are placed at intervals on the ground. There are at least 3 first layer composite pads 9, one at each end.

[0051] After the steel plates 10 come off the heat treatment furnace, they are directly stacked on the first layer of composite pads 9.

[0052] After the steel plates 10 (i.e. the first bundle of steel plates 10) on the first layer of composite pad 9 have reached the design requirements in terms of stacking thickness, the second layer of composite pad 9 is placed on top of the first bundle of steel plates 10, and the position of the second layer of composite pad 9 corresponds to the position of the first layer of composite pad 9.

[0053] The steel plates 10 of the heat treatment furnace are stacked sequentially on the second layer of composite pads 9 until the stacking thickness of the second bundle of steel plates 10 reaches the design requirements; the composite pads 9 are set up and the steel plates 10 are stacked in the same way until the overall stacking height reaches the design requirements.

[0054] In this embodiment, three composite cushions 9 are provided in each layer.

[0055] In this invention, the upper and lower pads 2 are made of copper, and the middle pad 3 is made of heat-insulating and fire-resistant material. This composite structure ensures the strength and heat resistance of the pads, as well as their heat insulation. It can not only increase the initial temperature of the steel plate 10 stacking, but also minimize the damage of the pads to the heat transfer conditions between the outer surface of the stacked steel plate 10 and the environment, thereby improving the cooling uniformity of the steel plate 10 and thus improving the quality stability of the steel plate 10.

[0056] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0057] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. However, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A composite pad for stacking steel plates, characterized in that, Includes an upper pad, a lower pad, and a middle pad; Both the upper and lower pads are made of copper. The middle pad block consists of multiple blocks, which are fixed at intervals between the upper pad plate and the lower pad plate; The two adjacent middle pads, the upper pad, and the lower pad together enclose and form an air channel; The stacked steel plates are placed on the upper pad; The middle pads are arranged at intervals along the horizontal and vertical directions. Two adjacent middle pads in the horizontal direction form a horizontal air channel together with the upper and lower pads, and two adjacent middle pads in the vertical direction form a vertical air channel together with the upper and lower pads.

2. The composite pad for stacking steel plates as described in claim 1, characterized in that, The centerlines of the lateral and longitudinal air channels intersect perpendicularly.

3. The composite pad for stacking steel plates as described in claim 1 or 2, characterized in that, The intermediate pad block is made of heat-insulating refractory brick.

4. The composite pad for stacking steel plates as described in claim 3, characterized in that, The thermal conductivity of the intermediate pad is <3W / (m·℃).

5. The composite pad for stacking steel plates as described in claim 4, characterized in that, The thickness of the upper and lower pads is 5~10mm.

6. The composite pad for stacking steel plates as described in claim 4, characterized in that, The outer side of the end pad is connected to the upper or lower pad through the first fixing plate.

7. The composite pad for stacking steel plates as described in claim 4, characterized in that, The inner side of the end pad and both sides of the middle pad are connected to the upper pad or the lower pad through L-shaped second fixing plates, respectively.

8. A method for stacking steel plates, characterized in that, The method is as follows: Prefabricate multiple composite pillows as described in any one of claims 1 to 7; Based on the length of the stacked steel plates, place the first layer of composite pads at intervals on the ground. The first layer of composite pads shall have at least 3 pads, with one pad at each end. After the steel plates come off the heat treatment furnace, they are directly stacked on the first layer of composite pads. After the steel plates on the first layer of composite pads reach the design requirements, the second layer of composite pads is placed on top of the first bundle of steel plates, with the position of the second layer of composite pads corresponding to the position of the first layer of composite pads. The steel plates for the heat treatment furnace are stacked sequentially on the second layer of composite pads until the stacking thickness of the second bundle of steel plates reaches the design requirements. Set up the composite pads and stack the steel plates using the same method until the overall stacking height reaches the design requirements.

9. The steel plate stacking method as described in claim 8, characterized in that, Each layer has three composite cushions.

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