Description of each component of the mold assembly (mold copper tube, outer water jacket, etc.)The mold assembly should have the following characteristics: lig

Description of each component of the mold assembly (mold copper tube, outer water jacket, etc.)

The mold assembly should have the following characteristics: light weight and good structural rigidity, good inertia force when vibrating, simple structure, convenient disassembly and assembly, adjustment, and easy processing and manufacturing.

The billet mold assembly is composed of the following parts: mold copper tube, outer water jacket, inner water jacket, upper and lower sealing flanges, various sealing rings, foot roller device, and foot roller area spray device. The mold copper tube is the core part, and other parts are assembled around the copper tube.

1. The mold copper tube is made of copper or copper alloy, and the length is 700-1000mm. If the copper tube is short and the drawing speed is high, breakout is likely to occur; if the copper tube is too long, it will increase the drawing resistance and cause transverse cracking of the cast slab. At present, the requirements of various steel mills on the pulling speed are increasing, so the length of the copper pipe is usually set at 850mm and 900mm.

2. The influence of cooling water gap on the quality of cast slab

The cooling water gap is the water channel between the copper tube of the mold and the inner water jacket, and its size and accuracy affect the quality of the cast slab. The general size is 4mm, and the accuracy is ±0.2mm. And try to be even.

3. Foot roller device

The foot roller device at the lower part of the crystallizer has two functions. One is to guide the head of the starter when threading the starter, and prevent the copper pipe from being scratched. The second is to have a clamping effect on the cast slab that has just exited the mold, especially for the correction of the cast slab with a slight squaring phenomenon.

4 Spray device

The spray device in the foot roller area is called 0 section. The distribution of this section of cooling water is very important: the billet shell just out of the mold is relatively thin (about 10mm), weak cooling is likely to cause leakage, and if the cooling is too strong, it may sometimes cause defects such as internal cracks; if the cooling distribution is uneven, it is easy to Defects such as missing squares, depressions, and longitudinal cracks occur. The spray device usually uses 2 to 3 rows of flat nozzles.

When the slab is inside the mold, the corner of the slab is the first to break away from the copper tube; when it comes out of the mold, the shell of the corner is the thinnest. It is necessary to add angular spray on the top row of spray rings. It can increase the thickness of the corner blank shell and reduce the defects such as splitting and longitudinal corner cracking.

5 Sealing of the mold

Since there is a water pressure of 0.7 to 1.2 MPa inside the crystallizer, the rationality of the sealing structure is very important to the safety of the crystallizer in use and to ensure smooth production. The sealing of the crystallizer mainly refers to the sealing of the upper and lower end flanges of the copper pipe and the sealing of the inner and outer water jackets.