The cold-rolled narrow strip is made of hot-rolled narrow-belt steel, and a narrow strip steel having a thickness of not more than 4 mm and a width of not more than 600 mm is produced by a cold rolling method.
The traditional process of cold rolled strip production consists of several steps of pickling, rolling, annealing, cutting, quenching and finished product packaging. In the current cold-rolled narrow strip steel industry, the level of equipment in each process is uneven, and there are advantages and disadvantages, but in general, the level of production equipment of broadband steel is quite different. However, the production characteristics of cold-rolled narrow strip steel determine that the equipment level does not need to be as high as the broadband steel production equipment. How to ensure the production equipment level of cold-rolled narrow strip steel has certain characteristics compared with today's environmental protection and quality.
2.1 Pickling production process equipment In the past, the box type sulfuric acid pickling method was widely used in the production of cold rolled high quality narrow strip steel. After several years of development, the continuous pickling line has been widely used in various cold-rolled narrow strip steel production plants, but the equipment level is generally backward, and the current production line needs to solve the following problems.
(1) Treatment of acid mist and waste acid. Acid mist not only increases acid consumption, corrodes plant and equipment, but also corrodes the surface of steel strips that are not transported in time, and puts a lot of pressure on the environment.
(2) A pickling heating device. Most manufacturers consider the investment cost to use steam as a heat source to directly or indirectly heat the acid solution, lack the acid temperature control system, affect the stability of the pickling quality and the production capacity and waste energy. It is recommended to use pickling temperature control equipment.
(3) Pickling speed. In the pickling line, the speed can be adjusted. As the pickling is extended, the acidity decreases, the ferrous ion increases, and the pickling time must be prolonged. To avoid the occurrence of acid or acid in the surface of the steel strip, waste acid. It is recommended to use frequency conversion technology in the production line to make the continuous pickling speed turn into adjustable speed.
For the future development, after the hot-rolling tropical production line, multi-party capital cooperation should be adopted to build a technologically advanced tower-type continuous pickling line with the same level of broadband, and the waste acid liquid should be reduced by hydrochloric acid regeneration technology to replace the current equipment. The level is generally backward, with a wide range of points, a wide range of pollution, and a relatively concentrated continuous pickling line. The cold-rolled strip mill directly uses the pickled rust-proof strip steel after pickling, thus completely solving the environmental impact of the cold-rolled strip mill, reducing the production cost and making the production environment truly clean.
Cold Rolled Galvanized Steel Coil
