Cement is an important basic raw materials of national economic construction, there is no one material can replace its status at home and abroad. With China’s rapid economic development, the role of the cement in the national economy is growing. As an important basic industry of the national economy, the cement industry has become an important symbol of social development level and the overall strength of the national economy. Since the reform and opening up, expanding domestic economic construction, promote the rapid development of the domestic cement industry.

According to statistics, in 1978 China’s cement production was 65.24 million tons, 1 November 2010, the national total cement output reached 1.7 billion tons. Or industry, the traditional peak season in December, based on past production and sales situation this year is estimated in December the national cement production is expected to reach about 150 million tons, therefore, it is expected this year will exceed 1.85 billion tons of cement production. Our annual net increase of nearly 1.8 billion tons of cement. Since 1985, China’s cement production has been 25 consecutive years ranked first in the world, now accounts for more than half the world’s total output of cement. The rapid growth of cement production, from the number has been basically to meet the needs of large-scale economic construction.

Ore strength and hardness coefficient:
The strength of stone. The so-called Platts hardness factor (f) is the ultimate compressive strength of ore (σ pressure) divided by 100. The resulting value. By size Platts hardness coefficient can be divided into five ore hardness level>

Platts hardness grade ore ore hardness coefficient is very soft, for example <2 bituminous coal, lignite, water quenched slag, ash, clay, mix 2-4 soft limestone, shale, clayey sandstone, slag, coal gangue 4-8 in a hard limestone, gypsum, quartz sandstones, fluorite, hard clinker kiln 8-10 hard limestone, hard sandstone, iron ore, quartzite hard> 10 granite, basalt, quartzite hard