What is Mesh?

What is Micron?

Micron also called um is a length unit which is 0.001mm or 0.00003937inch, usually to describe the tiny particles size, and aperture size of the mesh fabric in industrial filtration. The Micron size of mesh should be smaller than the particle size in the fluid to capture them.

The relationship between Mesh and Micron
The higher mesh count means there are more holes and wire density in unit length, so the micron of aperture decreasing. But they are not fixed proportion as the different mesh count has different yarn diameter (thickness).

How to calculate the Aperture Micron (Mesh Opening)?
M=Mesh Count
R=Yarn diameter (mm)
A=Aperture
Aperture=25.4/(divided)Mesh Count-Yarn Diameter
For example: 100mesh count with thread diameter 0.1mm (100um), its aperture (mesh opening) is 25.4/100 – 0.1=0.154mm (154um).
200mesh count with thread diameter 0.05mm(50um), its aperture (mesh opening) is 25.4/200-0.05=0.077 mm(77um)

Mesh VS Micron Chart (Nylon & Polyester general)

Mesh Count		Mesh Opening
mesh/inch	mesh/cm	Micron	mm	inch
12	5	1566	1.566	0.0617
16	6	1188	1.188	0.0467
18	7	1061	1.061	0.0418
20	8	920	0.920	0.0362
24	9	808	0.808	0.0318
25	10	766	0.766	0.0302
30	12	547	0.547	0.0215
35	14	476	0.476	0.0187
40	16	435	0.435	0.0171
50	20	308	0.308	0.0121
60	24	273	0.273	0.0107
70	28	212	0.212	0.0083
80	32	217	0.217	0.0085
90	36	182	0.182	0.0072
100	40	154	0.154	0.0061
110	43	174	0.174	0.0069
120	48	132	0.132	0.0051
140	56	121	0.121	0.0048
150	59	109	0.109	0.0043
160	64	99	0.099	0.0039
180	72	91	0.091	0.0036
200	80	77	0.077	0.0030
230	90	70	0.070	0.0028
250	100	62	0.062	0.0024
280	110	51	0.051	0.0020
305	120	43	0.043	0.00169
330	130	37	0.037	0.00145
355	140	35	0.035	0.00137
400	157	25	0.025	0.00098
430	169	20	0.020	0.00078
470	185	15	0.015	0.00059
530	208	9	0.009	0.00035