Classification and application
1. Cold-formed steel is classified according to dimensions and specifications, and divided into four types according to product thickness and unfolded width: large, medium, small and wide.
(1) large cold-formed steel: product thickness is 6- 16mm, and product spread width is 600-2000 mm.
(2) Medium-sized cold-formed steel: the product thickness is 3-6mm, and the product spread width is 200-600mm.
(3) Small cold-formed steel: the product thickness is1.5-4mm, and the product spread width is 30-200mm.
(4) wide cold-formed steel: the product thickness is 0.5-4 mm, and the developed width of the product is 700- 1600 mm. ..
2. Cold-formed steel can be divided into two types according to its shape: open type and closed type.
(1) Universal open-ended cold-formed steel includes equilateral and unequal angle steel, internal and external rolled angle steel, equilateral and unequal channel steel, internal and external rolled channel steel, Z-shaped steel, rolled Z-shaped steel and special-shaped open-ended steel.
(2) Closed cold-formed steel is welded cold-formed steel with closed cross section, and its shapes are round, square, rectangular and irregular.
3. Cold-formed steel is classified according to use, and different industries have different requirements for cold-formed steel. Cold-formed steel manufacturers can meet the different requirements of different industries and produce all kinds of special cold-formed steel. Mainly can list the following items.
(1) cold-formed steel for automobile manufacturing; Small passenger cars mostly use special-shaped open steel, such as windows, rain gutters and landline pulleys. Most passenger cars use closed rectangular steel, and most freight cars use open cold-formed steel; Fire trucks, engineering vehicles and other special vehicles mostly use rectangular and special-shaped cold-formed steel.
(2) Railway vehicles: Most passenger cars and freight cars use special-shaped cold-formed steel beams, such as cold-formed center beams instead of hot-rolled center beams. For a long time, open your eyes
The center beams used in the chassis of cars, caravans and tankers are all hot-rolled I-beams, which are made of two hot-rolled I-beams with a height of 365,438+00. Because the center sill is made of hot rolled steel, it has heavy weight, high welding quality (requiring nondestructive testing), many working procedures and high comprehensive cost. Therefore, the railway department hopes to develop an integrated, lightweight, high-strength and high-efficiency cold-formed steel to replace the hot-rolled I-beam. The cold-formed center sill developed by WISCO uses hot-rolled coil as raw material, and the integral center sill is obtained through continuous forming. For another example, in 1985, Qiche Group developed cold-formed steel for end wall transverse belt and cap steel side column, and in 1993, it developed cold-formed steel for upper side beam of acute-angle rectangular pipe, which is made of cold-formed steel 09CuPTiRE-A with yield strength of 295MPa. The application of cold-formed steel in railway freight cars in China will be more and more.
(3) Elevator: hollow guide rail for elevator, cold-formed steel for structural frame and other special-shaped components for automatic elevator.
(4) Shelves: cold-formed steel for small supermarket shelves and large warehouse supermarket shelves.
(5) Transmission tower: Cold-formed steel is mainly used to replace traditional hot-rolled angle steel to improve the comprehensive performance of the tower and reduce the cost. In high-voltage long-distance transmission towers, high-strength corrosion-resistant structural steel pipes have been tried in various places. The triangular tower structure made of cold-formed steel for communication tower is also being developed.
(6) Construction machinery: cold-formed steel for crane boom, support arm and tower frame.
(7) Electrical equipment manufacturing: cold-formed steel for electrical cabinets and cable bridges.
(8) Agricultural machinery: cold-formed steel for tractors, plows, harrows and harvesters, and cold-formed steel for agricultural vehicle beams.
(9) Construction industry: cold-formed steel for steel structure (beam and column) maintenance structure, roof, wall, doors and windows, and decoration.
(10) Furniture: stools, chairs, cabinets and beds are all made of special cold-formed steel.