What Is The Unit Mesh?

What is the unit mesh?

The mesh size of the unit of measurement refers to the size of the raw material particles, which is generally expressed by the maximum length of the particles. The mesh is the size of the mesh size of the standard sieve. In the Taylor standard sieve, the so-called mesh is the number of sieve openings in a length of 2.54 cm (1 inch) and is referred to as the mesh for short.

The number of meshes is the number of holes, which is the number of holes per square inch. The larger the mesh, the smaller the aperture. Generally speaking, the number of meshes × aperture (number of microns) = 15000. For example, the aperture of a 400 mesh screen is about 38 microns; the aperture of a 500 mesh screen is about 30 microns. Due to the problem of opening rate, that is, because of the difference in the thickness of the wire used in weaving the net, the standards of different countries are different. There are currently three standards: the United States, the United Kingdom and the Japanese standard. The United Kingdom and the United States are similar. , Japan is quite different. Our country uses the American standard, that is, it can be calculated by the formula given below.

Sieve inner diameter (μm)≈14832.4/sieve mesh

The larger the mesh, the finer the particles. Similar to the magnification of the metallographic structure.

The plus or minus sign before the mesh indicates whether the mesh of the mesh can be missed. A negative number means that the mesh can pass through the mesh, that is, the particle size is smaller than the mesh size; while a positive number means that the mesh cannot pass the mesh, that is, the particle size is larger than the mesh size. For example, the particle size is -100 mesh to +200 mesh, which means that these particles can leak through the 100 mesh but cannot leak through the 200 mesh. When screening particles of this mesh size, the mesh number should be large ( 200) is placed under the small mesh (100) screen, and the particles left in the large mesh (200) screen are -100~200 mesh particles.