CN202169362U - Casting blank heat insulation cover for fan-shaped segment of continuous casting machine and region of withdrawal and straightening unit - Google Patents

Abstract

The utility model discloses a casting blank heat insulation cover for a fan-shaped segment of a continuous casting machine and a region of a withdrawal and straightening unit, which is characterized in that: the heat insulation cover is composed of a steel outer wall (1), a heat insulation layer (2) and a counter radiation screen (3) arranged from outside to inside, wherein the heat insulation layer (2) is a zirconium-containing ceramic fiber carpet. The casting blank heat insulation cover has good heat insulation effect, and can promote the casting blank surface temperature to be rose, avoid the crack sensitive temperature and effectively reduce the risk of the casting blank crack.

Description

A slab thermal insulation cover for the continuous casting machine segment and the stretching and leveling machine area

technical field

The utility model relates to a slab thermal insulation cover in continuous casting production.

Background technique

The high-temperature mechanical properties of steel are directly related to the cracks of continuous casting slabs. As shown in Figure 1, when the temperature is lower than 900 °C, the plasticity of steel decreases significantly. Therefore, in continuous casting production, it is generally required that the surface temperature of the slab in the straightening zone is greater than 900°C to avoid cracks. In the production of blooms and blooms, due to the low pulling speed and the long residence time of the slab, the surface temperature of the slab in the straightening zone is too low, and the slab is prone to cracks. However, because the end of the flange of the H-shaped billet is thinner and belongs to two-dimensional heat transfer, the temperature of the end of the flange is lower before the straightening zone, and cracks are easily generated during the straightening process. In order to solve the above problems, it is usually necessary to set a heat preservation cover between the fan section in front of the tension leveler and the tension leveler, as shown in Figure 2.

The form of the heat preservation cover currently used is to fill the steel structure cover with heat insulating material, so that the ambient temperature around the billet is relatively high, which belongs to the heat insulation type heat preservation cover. Due to the limited ambient temperature achieved, the effect of using a thermal insulation cover is not obvious. The solid curve in Figure 3 is the surface temperature of the slab using a conventional thermal insulation cover, and its thermal insulation effect is not ideal.

Utility model content

The purpose of the utility model is to propose a thermal insulation cover that can effectively increase the surface temperature of the slab, avoid the brittle zone, and avoid the slab thermal insulation cover in the segment of the continuous casting machine and the area of the stretching and straightening machine where cracks appear in the slab.

In order to achieve the above purpose, the following technical solution is adopted: a slab thermal insulation cover for the continuous casting machine segment and the stretching and straightening machine area, characterized in that: the thermal insulation cover is composed of a steel structure outer wall from outside to inside, a heat insulation layer and an inversion The radiation screen consists of three layers.

The thermal insulation layer is a zirconium-containing ceramic fiber blanket.

The reverse radiation screen is a far-infrared radiation paint layer sprayed on the surface of the heat insulating layer, with a thickness of 3mm-8mm.

The anti-radiation screen is made of stainless steel plate, and the thickness of the stainless steel plate is 0.05mm-1.5mm.

The reverse radiation screen is a stainless steel plate sprayed with a far-infrared radiation paint layer. The thickness of the steel plate is 0.05mm-1.5mm, and the thickness of the paint layer is 2mm-5mm. The far-infrared radiation paint layer is located inside the billet insulation cover.

In the utility model, since the reverse radiation screen is very thin, the heat required for its temperature rise is very little, and the heat balance with the billet can be realized quickly, which is beneficial to increase the surface temperature of the continuous casting head billet and reduce the cracks of the billet The probability of production increases the metal yield of continuous casting slabs.

Description of drawings

Fig. 1 is the relationship diagram of high temperature ductility and temperature of steel;

Fig. 2 is a typical setting diagram of an existing continuous casting machine insulation cover;

Fig. 3 is a comparison chart of heat preservation effects of different heat preservation cover types;

Fig. 4 is a structural schematic diagram of the utility model.

In the figure, item 1 is the outer wall of the steel structure; item 2 is the heat insulation layer; item 3 is the reverse radiation screen; item 4 is the circular blank; item 5 is the billet; item 6 is the H-shaped blank; 8 is the sector section or the basic frame of the tension leveler.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the utility model is described further.

As shown in Figure 4, it is a slab thermal insulation cover for the continuous casting machine sector and the tension leveler area. The thermal insulation cover includes a steel structure outer wall 1, a thermal insulation layer 2 and a reverse radiation screen 3, wherein the thermal insulation layer 2 is located on the steel structure outer wall 1 Between and the anti-radiation screen 3, the thermal insulation layer 2 is a zirconium-containing ceramic fiber blanket.

Described anti-radiation screen 3 has three kinds of forms to choose from. Form 1: spraying far-infrared radiation paint on the inner surface of the heat insulating layer 2, the paint layer is the reverse radiation screen, the thickness of the paint layer is 3mm-8mm; form 2: stainless steel plate, the thickness of the steel plate is 0.05-1.5mm; form 3: The stainless steel plate sprayed with far-infrared radiation paint, the thickness of the steel plate is 0.05mm-1.5mm, the thickness of the paint layer is 2mm-5mm, and the paint layer must face the casting slab.

When the billet passes through the insulation cover, the heat radiated by the billet makes the temperature of the reverse radiation screen rise rapidly, and the heated reverse radiation screen radiates heat to the billet. Through this kind of radiation and reflection, the temperature of the reverse radiation screen is almost as high as the temperature of the casting slab. Since the temperature difference between the two is small, the heat radiation loss of the casting slab is also very small. Since the internal temperature of the slab is higher than the surface, and there is also the release of solidification latent heat, the heat transferred from the inside to the outside of the slab is greater than the heat lost by radiation, so in the insulation cover of the utility model, the surface temperature of the slab will be picked up instead. , as shown by the dotted line in Figure 3. At this time, the diameter of the big round billet is 600mm; the casting speed is 0.4m/min.

The utility model has a good heat preservation effect, can promote the rise of the surface temperature of the slab, avoids the crack sensitive temperature, and effectively reduces the risk of the slab crack.

Claims (5)

1. A slab thermal insulation cover for the continuous casting machine segment and the tension leveler area, characterized in that: the thermal insulation cover is composed of a steel structure outer wall (1), a thermal insulation layer (2) and a reverse radiation screen from the outside to the inside (3) Composed of three layers. 2. The slab insulation cover of the continuous casting machine sector and the stretch leveler area according to claim 1, characterized in that: the heat insulation layer (2) is a zirconium-containing ceramic fiber blanket. 3. The slab insulation cover of the continuous casting machine segment and the stretching and straightening machine area according to claim 1 or 2, characterized in that: the reverse radiation screen (3) is sprayed on the surface of the heat insulation layer (2) The far-infrared radiation coating layer has a thickness of 3mm-8mm. 4. The slab heat preservation cover for the continuous casting machine segment and the stretching and straightening machine area according to claim 1 or 2, characterized in that: the reverse radiation screen (3) is made of stainless steel plate, and the thickness of the stainless steel plate is 0.05mm -1.5mm. 5. The slab insulation cover of the continuous casting machine segment and the stretching and straightening machine area according to claim 1 or 2, characterized in that: the reverse radiation screen (3) is a stainless steel plate sprayed with a far-infrared radiation coating layer, The thickness of the steel plate is 0.05mm-1.5mm, the thickness of the paint layer is 2mm-5mm, and the far-infrared radiation paint layer is located inside the casting slab insulation cover.

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