Coke indicators are divided into grades
Coke is a solid product of high temperature carbonization, the main component is carbon, is a crack and irregular pore structure (or porous). The number of cracks has a direct impact on the strength and crushing strength of the coke, the index is generally measured in terms of crack degree (the number of cracks in the unit volume coke).
The index of pore structure is mainly expressed by the porosity rate (the percentage of the total volume of coke), which affects the reactivity and strength of coke. Different uses of different coke porosity index requirements, the general requirements of metallurgical coke porosity in the 40 ~ 45%, 35 ~ 40% in coke, coke export demand in about 30%. Coke crack degree and the porosity level, and the coking coal has a direct relationship, such as coal based coke refining, crack, high porosity, low strength; with coal as the foundation of the coal refining coke crack less, low porosity and high strength
Coke crushing strength refers to coke can resist foreign impact force without ability along cracks or defects at the broken, represented by the M40 value; wear strength of coke coke refers to the ability to resist external friction without surface of glass forming debris or powder, said M10. The cracking degree of coke affects the M40 value of its breaking strength, and the pore structure of coke affects the M10 value. There are many methods for determination of M40 and M10 value method, commonly used in our country the German migon drum test.