The particle size of the powder is called the particle size. Due to the complexity of the particle shape, there are usually several representation methods such as sieve size, sedimentation particle size, equivalent volume particle size, and equivalent surface area particle size. The sieve size is the size of the sieve through which the particles can pass through the screen, and is expressed as the number of sieves in the screen of 1 inch (25.4 mm) width, and is therefore referred to as "mesh". At present, there is no uniform technical standard for powder particle size at home and abroad, and each enterprise has its own definition and representation method of particle size index. Screen specifications in different countries and different industries have different standards, so the meaning of “mesh” is difficult to unify.

Our company adopts two methods of sieving and grading for powder, and adopts sieving treatment within 200 mesh, and grading treatment for more than 200 mesh.