1. Introduction of ordinary cold-rolled sheet is a product obtained from hot-rolled sheet by cold pressure processing.
Due to the multi-pass cold rolling, the surface quality is better than that of the hot-rolled sheet, and good mechanical properties can be obtained after heat treatment.
1. Classification of use of ordinary cold-rolled sheets According to the different needs of manufacturers, cold-rolled sheets are usually divided into: general cold-rolled sheets, stamping-grade cold-rolled sheets, deep-drawing, extra-deep-drawing and ultra-deep-drawing cold-rolled sheets , Generally delivered in coils and flat sheets, the thickness is expressed in millimeters, the width is generally 1000mm and 1250mm, and the length is generally 2000mm and 2500mm.
2. The common grades of ordinary cold-rolled sheets are: Q195, Q215, Q235, 08AL, SPCC, SPCD, SPCE, SPCEN, ST12, ST13, ST14, ST15, ST16, DC01, DC03, DC04, DC05, DC06, etc.; ST12 : indicates the most common steel grade, which is basically the same as the Q195, SPCC, DC01 grades; ST13/14: indicates the stamping grade steel grade, which is basically the same as the 08AL, SPCD, DC03/04 grades; ST15/16: indicates It is a stamping grade steel, basically the same as 08AL, SPCE, SPCEN, DC05/06 grades.
3. The size representation method of the grade of ordinary cold-rolled sheet, such as ST12 produced by Anshan Iron and Steel, 1*1250*2500/C, expressed as: grade ST12 ordinary cold sheet, thickness 1mm, width 1250mm, length 2500mm or C coil. The appearance is finely packaged in white iron, and the mechanical properties are the most common and basic steel grades, which can only be used for bending and forming, not for stamping. Used for mechanical bites, such as refrigerator shells, vehicle fuel tanks, etc. Products above ST13 are used in industries that require deep drawing, such as automobile manufacturing, fuel tanks for diesel engines, etc. The specific type to be used depends on the deep drawing requirements.
The difference between ST12 and SPCC: The mechanical properties of the two products are almost the same, but the annealing method is different. The tensile properties of ST12 materials are relatively stronger than SPCC. Japanese JIS standard material meaning SPCC—S means steel (Steel), P means plate (Plate), C means cold (Cold), C means commercial (Commercial), which is the Japanese JIS standard. To ensure the tensile strength, add T at the end of the grade: SPCCT. SPCD—represents cold-rolled carbon steel sheet and strip for stamping, which is equivalent to China 08AL (13237) high-quality carbon structural steel. SPCE—represents cold-rolled carbon steel sheet and strip for deep drawing, which is equivalent to China 08AL (5213) deep drawing steel. To ensure non-timeliness, add N at the end of the grade to be SPCEN. Cold-rolled carbon steel sheet and strip quenching and tempering code: annealing state is A, standard quenching and tempering is S, 1/8 hardness is 8, 1/4 hardness is 4, 1/2 hardness is 2, and full hardness is 1. Surface processing code: dull finish rolling is D, bright finishing rolling is B. For example, SPCC-SD represents a general-purpose cold-rolled carbon sheet with standard quenching and tempering and matte finish rolling. Another example is SPCCT-SB, which means standard quenching and tempering, bright processing, and cold-rolled carbon sheet that requires guaranteed mechanical properties. Another example is SPCC-1D, which represents a hard matte finish-rolled cold-rolled carbon steel sheet.
The representation method of steel grade for mechanical structure is: S + carbon content + letter code (C, CK), in which the carbon content is represented by the intermediate value * 100, the letter C represents carbon, and the letter K represents steel for carburizing. Such as carbon knot coil S20C, its carbon content is 0.18-0.23%. The meaning of Chinese GB standard materials is basically divided into: Q195, Q215, Q235, Q255, Q275 and so on. Q represents the first letter of the Chinese pinyin of the word “Qu” for the yield point of steel, and 195, 215, etc. represent the value of the yield point. In terms of chemical composition, low carbon steel grades: Q195, Q215, Q235, Q255, Q275 The higher the carbon content and manganese content, the more stable its plasticity is.
2. Introduction of hot-dip galvanized steel sheet (silver white) is produced by continuous hot-dip galvanizing process with hot-rolled steel strip or cold-rolled steel strip as the substrate, which can prevent the surface of thin steel plate and steel strip from corroding and rusting. Hot-dip galvanized sheets are supplied in rectangular flat plates after cross-cutting; hot-dip galvanized coils are supplied in coils after coiling. Due to the different substrates used, hot-dip galvanized steel sheets can be divided into hot-rolled galvanized sheets and coils and cold-rolled hot-dip galvanized sheets and coils, which are mainly used in construction, home appliances, automobiles, containers, transportation and household industries. Especially in steel structure construction, automobile manufacturing, steel window manufacturing and other industries.
1. The characteristics of hot-dip galvanized steel sheet are strong corrosion resistance, good surface quality, favorable for deep processing, economical and practical, etc.
2. The classification and symbols of hot-dip galvanized steel sheets are divided into: general purpose (PT), mechanical engagement (JY), deep drawing (SC), super deep drawing aging (CS), structure (JG) according to the processing performance; Weight is divided into: pure zinc surface is divided into: 100/100 (zinc layer weight is less than 100g/m2), 120/120, 200/200, 275/275, 350/350, 450/450, 600/600; zinc-iron alloy surface Divided into: 90/90 (the weight of zinc-iron alloy layer is less than 90g/m2), 100/100, 120/120, 180/180; according to the surface structure: normal spangle Z, small spangle X, smooth spangle GZ , Zinc-iron alloy XT; According to surface quality, it is divided into: I group (I), II group (II); According to dimensional accuracy, it is divided into: advanced precision A, ordinary precision B; According to surface treatment, it is divided into: chromic acid passivation L, coating Oil Y, chromic acid passivation plus oil LY.
Baosteel hot-dip galvanized steel sheet: Baosteel Phase II Hot-dip Galvanizing Baosteel’s Phase II hot-dip galvanizing is produced by continuous dipping galvanizing of cold tandem or hot tandem rolled steel on the 2030 unit for general purpose or structural use.
The scope of supply of the second phase of hot-dip galvanizing: thickness (0.3-0.3) width (800-1830) length (plate 1000-6000, coil inner diameter 610) unit mm.
The second-stage hot-dip galvanizing is divided according to the surface structure: Z means normal spangle, N means zero spangle, X means small spangle, and G means smooth spangle.
The second-stage hot-dip galvanizing is divided according to surface treatment: L means chromic acid passivation, Y means oiling, LY means chromic acid passivation + oiling is mainly to reduce or avoid white rust during transportation or storage.