What is abrasive grain
Abrasive particle size refers to the degree of abrasive particle size.Abrasive size specifications are represented by size number.
The national standard of abrasive materials divides the particle size into two categories: one is the abrasive grain size of the consolidated abrasive tool, grinding and polishing. The particle size number is "F", which is called "F particle size ";The other type is the grinding grain size specification for coating abrasive, whose particle number is "P", and it is called "P particle size abrasive ".
(1) f-size specification
Ordinary abrasive particle size is divided into 39 particle size, and its screen ratio is 1.1892, i.e
Coarse abrasive grains F4, F5, F6, F7, F8, F10, F12, F14, F16, F20, F22, F24, F30, F36, F40, F46, F54, F60, F70, F80, F90, F100, F120, F150, F180, F220,
Micro powder F230, F240, F280, F320, F360, F400, F500, F600, F800, F1000, F1200, F1500, F2000.
According to the abrasive production process, the abrasive particle size in the parts of F4~F220 is called "rough abrasive grain", and its abrasive size is more than 63 m.The abrasive particle size is within the range of F230~F2000, and the abrasive size smaller than 63 m is called "micro powder".
The particle size composition of coarse abrasive abrasive, F230~F2000 fine powder abrasive (photoelectric sedimentation particle size) and F230~F2000 fine powder abrasive particle size composition are shown in the standards of gb-t 2481-2009.
(2) size P
Use the P particle size abrasive in the coated abrasives (P is the first letter of popular).According to national standards, the abrasive has 28 particle size, that is
Rough abrasive P12, P16, P20, P24, P36, P40, P50, P60, P80, P100, P120, P150, P180, P220
Fine abrasive P240, P280, P320, P360, P400, P500, P600, P800, P1000, P1200, P1500, P2000, P2500.
P12~P220 abrasive material is coarser, and its screen ratio is 1.892.P240~P2500 abrasive material is coarse and divided into abrasive, and the screen ratio is 1.120 -- 1.589 -- 1.196.
(3) the particle size of ultra-hard abrasive
Gb-t 6406-1996 is equivalent to ISO 6106-1979 "superhard abrasive products - diamond or cubic boron nitride particle size", with a total of 25 particle size Numbers and a screen ratio of 1.892. It has a narrow range of 20 and a wide range of 5.The range of size of each size number is represented by the range of mesh size of the screen above and below this size.The particle size range and particle size composition of each particle size number can be seen in GB-T 6406-1996.
(4) particle size composition
Each particle size, abrasive products is not a single dimension of particle swarm, screen mesh size is limited to two adjacent aperture between particle swarm, but across several set of mesh number of particle swarm, in various grain sizes of abrasive size range and the quality of the each grain sizes of each grain group proportion relations, the grain sizes of abrasive particles is divided into five group, namely, the coarse grain, coarse grain, basic grain and mixed grain and fine grain.The basic grain refers to the grain group between the corresponding size of the screen mesh and the adjacent size of the hole size of the first coarse screen mesh.Coarse grain is a coarser grain group most adjacent to the basic grain.A fine grain is a group of finer grains adjacent to the basic grain.The coarsest grains are larger than the coarsest grains.The mixed grain is the sum of the basic grain group and the neighboring finer grain group.
Take the abrasive of F36 as an example to illustrate the size range of each grain group, as shown in FIG. 1-2.The composition of abrasive grain is to measure and calculate the mass fraction of each grain group.
According to the national standard, the particle size number of the powder is F230~F2000, which is detected by photoelectric sedimentation instrument.The subsidence tube grain-size meter was used to detect the difference of R from 1.173 to 1.305 to 1.197.
In the P series, the grain size of guojian standard mill is the public proportion of P12~P220, R=21/4=1.1892.The national standard stipulates that the particle size number of the powder is P240~P2500. If the sedimentation pipe particle size meter is used to detect, R is from 1.120 to 1.589 to 1.196, and there is no determined public ratio.
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Topic：2018 guilin autumn national abrasive and abrasive tool industry communication meeting