Silicon steel can be divided into hot-rolled silicon steel and cold-rolled silicon steel. Hot-rolled silicon steel is gradually being eliminated due to its low availability and high energy loss. Cold-rolled silicon steel is the focus of future development due to its high technical content and low loss. Cold-rolled silicon steel is divided into: cold-rolled oriented silicon steel and cold-rolled non-oriented silicon steel.
The main use of cold-rolled oriented silicon steel is for transformer manufacturing, so it is also called cold-rolled transformer silicon steel. HiB steel in oriented silicon steel is called high magnetic induction cold-rolled oriented silicon steel. Due to its good magnetic permeability and low loss characteristics, it is mainly used in various high-voltage transformers, chokes and other electromagnetic components in the telecommunications and instrumentation industries. In production. Non-oriented silicon steel is mainly used in generator manufacturing.
The two most important indicators of grain-oriented silicon steel are: magnetic induction and unit loss value. The higher the magnetic induction, the stronger the magnetic permeability, the smaller the iron core can be, and the iron loss and copper loss will be reduced. At the same time, the amount of material can be saved and the total cost can be reduced. The lower the specific loss value, the better it can be used in large transformers. Different types of oriented silicon steel can be applied to different voltage levels and types of transformers due to different indicators such as magnetic induction and loss.
For example, the 30Q130 grade oriented silicon steel produced by Wuhan Iron and Steel Co., Ltd. has a thickness of 0.30mm. Under standard conditions (800A/m alternating magnetic field, frequency 50Hz), the magnetic induction is 1.83T. Under standard conditions (magnetic induction is 1.7T, frequency 50Hz) iron The loss value is 1.3W/kg. Generally, 130 and below grades of oriented silicon steel are mainly suitable for transformers with voltage levels of 110kV and below. 120 grades (such as 30Q120, 27Q120) can be used for 220kV transformers, while 110 and above grades of oriented silicon steel can be used for 500kV and higher voltages. grade transformer.
High magnetic induction oriented silicon steel (HiB steel) has excellent magnetization characteristics. Under standard conditions, the magnetic induction is about 1.92T, while ordinary oriented silicon steel is 1.82T, which can effectively reduce the loss of the transformer. (HiB steel) Due to its low loss and high conductivity, it is mainly used in high-voltage transformers. my country's power grid construction will require more high-voltage transformers in the future. More use of low-loss high-voltage transformers will also be the future trend of the transformer market.
1. Chinese brand representation method:
(1) Cold-rolled non-oriented silicon steel strip (sheet) expression method: DW + iron loss value (at a frequency of 50HZ, the magnetic induction peak value of a sinusoidal waveform is the iron loss value per unit weight of 1.5T.) + 100 times the thickness value 100 times. For example, DW470-50 represents cold-rolled non-oriented silicon steel with an iron loss value of 4.7w/kg and a thickness of 0.5mm. The new model is now represented as 50W470.
(2) Expression method for cold-rolled oriented silicon steel strips (sheets): DQ + iron loss value (the iron loss value per unit weight at a frequency of 50HZ and a sinusoidal magnetic induction peak value of 1.7T.) + 100 times the thickness value times. Sometimes G is added after the iron loss value to indicate high magnetic induction. For example, DQ133-30 represents a cold-rolled oriented silicon steel strip (sheet) with an iron loss value of 1.33 and a thickness of 0.3mm. The new model is now represented as 30Q133.
(3) Hot-rolled silicon steel plate Hot-rolled silicon steel plate is represented by DR. According to the silicon content, it is divided into low silicon steel (silicon content ≤ 2.8%) and high silicon steel (silicon content > 2.8%). Representation method: DR + 100 times the iron loss value (the iron loss value per unit weight when the maximum magnetic induction intensity is 1.5T with 50HZ repeated magnetization and sinusoidal change) + 100 times the thickness value. For example, DR510-50 represents a hot-rolled silicon steel plate with an iron loss value of 5.1 and a thickness of 0.5mm. The grade of hot-rolled silicon steel sheet for household appliances is represented by JDR + iron loss value + thickness value, such as JDR540-50.
2. Japanese brand representation method:
(1) Cold-rolled non-oriented silicon steel strip is composed of nominal thickness (value expanded by 100 times) + code A + iron loss guaranteed value (value expanded by 100 times when the frequency is 50HZ and the maximum magnetic flux density is 1.5T) . For example, 50A470 represents a cold-rolled non-oriented silicon steel strip with a thickness of 0.5mm and a guaranteed iron loss value of ≤4.7.
(2) Cold-rolled oriented silicon steel strip is composed of nominal thickness (value expanded by 100 times) + code G: indicating ordinary materials, P: indicating high orientation materials + iron loss guaranteed value (frequency is 50HZ, maximum magnetic flux density is 1.7T The value after the iron loss value is expanded by 100 times). For example, 30G130 represents a cold-rolled oriented silicon steel strip with a thickness of 0.3mm and a guaranteed iron loss value of ≤1.
3. The American brand has
M15_24G, M15_26G, M19_24G, M19_26G, M19_29, M22_24G, M22_26G, M22_29G, etc. These brands are all American standards.
In addition, the silicon steel used in motors is anisotropic, non-oriented silicon steel, which is different from the isotropically oriented steel used in transformers. There are also pure iron grades steel_1008 and steel_1010 available. For squirrel cage cast aluminum rotors, cast_aluminum_75C can be selected.
my country's grain-oriented silicon steel (Wugang)-related production equipment and technology were introduced from Nippon Steel (NIPPON) in 1974, with a designed output of 28,000 tons. General grain-oriented silicon steel has three specifications and eight grades: 0.35 mm, 0.30mm, and 0.28mm; high Magnetic induction oriented silicon steel (HiB steel) has two specifications of 0.35mm and 0.30mm and 2 grades. Although my country's grain-oriented silicon steel has made great progress after nearly 30 years of development, there is still a big gap between China and developed countries in terms of product quality level, variety richness and the proportion of high-end products. At present, the dependence of products on foreign countries still exceeds 50%. , in 2009, with the expansion of Wuhan Iron and Steel Co., Ltd.'s production and Baosteel Co., Ltd.'s formal sales to the market, the degree of dependence on foreign countries will improve.
