Hot-rolled steel sheet / cold-rolled steel sheet: Steel ingots or slabs are difficult to deform at normal temperature and difficult to process. They need to be heated to 1100 ° C to 1250 ° C for rolling. This A514 grade B QT steel plate rolling process is called hot rolling. Rolling at room temperature is generally understood as cold rolling. However, from the point of view of metallurgy, the boundary between hot rolling and cold rolling should be distinguished by the temperature of metal recrystallization, that is, rolling below the recrystallization temperature is cold rolling; Rolling above the recrystallization temperature is hot rolling.
Medium and heavy plate A514 grade B QT steel plate inventory spot: 23*3190*9220, 23*2470*8400, 22.5*3050*7300, 23*3500*10800, 21*3500*8840, 22*3400*11550, 29.5*1750*7150, 25*2500*12000, 27*1500*5000, 36*2720*7950, 27*1920*6000, 25*2630*3300, 26*3480*6000, 27*1800*6000, 23*2430*12370, 22.5*2560*6000, 43.5*1600*6000, 28.5*2500*6700, 32*1850*6000, 27.5*3100*6390, 48.5*1600*6000, 23.5*3300*14000, 33*3500*7050, 50*1600*6000.
In September, China's apparent consumption of crude steel was 94.38 million tons, an increase of 15.58 million tons or 19.8% year-on-year. It has exceeded 90 million tons for five consecutive months. From January to September, China's apparent crude steel consumption was 770 million tons, an increase of 63.14 million tons or 8.9% year-on-year. In terms of growth rate, the apparent consumption of hot-rolled sheet and coated sheet (strip) from January to September increased by more than 40% year-on-year, and the growth rates were 42.6% and 42.0% respectively; railway steel and electrical steel strips fell year-on-year, with a decline. They are 12.8% and 1.4% respectively.
The basic principle of A514 grade B QT steel plate, heat treatment of steel: put the metal workpiece in a certain medium and heat it to a suitable temperature, keep it in this temperature for a certain time, and then cool it at different speeds. Objective: to obtain the desired structure and properties by means of heating, heat preservation and cooling, so as to make the metal workpiece have the required mechanical, physical and chemical properties.