Laboratory Test Sieves (SS Coarse / Fine Mesh)

• Laboratory test sieves are screening tools. Because that it usually consists of a stainless steel wire mesh held in a round metal frame. Screening is a physical method of separating mixtures by size. The smaller particles pass through the holes of the metal sieves and the larger ones are retained by it.
• Moreover, because it is comparatively inexpensive, simple in concept and easy to use.
• So screening sieves suit for assessing the particle size distribution of a granular material. Sieve analysis or gradation test often uses a set of sieves with different stainless steel wire meshes of graded mesh size. So how?
  • The material needs to pass through a series of laboratory sieves of progressively smaller size.
  • Each micron sieve will retain some part of material where size of particles over than the opening size of ss sieve mesh.
  • We can weight the material of each metal mesh sieve, and then know something about the size distribution of particles in the material.

Laboratory test sieves can vary widely in their woven wire mesh, like material, mesh count, wire diameter and opening size. And there are some choices for the metal frame.

• Material: The most commonly used type of mesh screen is stainless steel wire mesh. 300 series steel is the most popular, for example, 304SS, 316SS, 316SS.
• Mesh count: We can know from the mesh screen size chart, the mesh is available from number 2 to number 635 (at that time, micron size will down to 20). If dutch weave wire mesh is also suitable for you, micron size can down to 1 micron for now. So it suitable for separating many kinds of particles from materials. Because the mesh size can vary widely.
• For example, if only use one 100 micron sieve, particles smaller than 0.1 mm can pass through stainless steel sieve mesh, but larger ones cannot. So it divide the material into two sets.

• Material: Stainless steel and Chrome-plated iron are the most popular materials. Brass is also available.
  • Stainless steel

• • Chrome-plated iron

• • Brass

• Shape: The frame is usually in a round shape. Sometimes customers need test sieves with a square or rectangular metal frame. We can customize it as requirement, but its cost may be a little high and it will take more time to produce. Because for the round metal frame, related molds are available for producing. So cost of a round sieve is usually lower than a square or rectangular sieve.
• Size:
  • The standard round frame sizes in the U.S. are 3 inch, 8 inch, and 12 inch.
  • Internationally, 100mm, 200mm, and 300mm are the standard sizes.

The main function of the skirt is to allow stainless steel test sieves to be stacked without toppling over.

Mesh is a measurement of particle size, and then it’s often used for determining the particle size distribution of a granular material in sieve analysis or gradation test.

Mesh number is also known as sieve number. The numerical value indicates the number of openings / holes per linear inch of a stainless steel woven wire mesh. For instance,

• The steel screen used in 8 mesh sieve has 8 holes per linear inch in both directions.
• The ss screen used in 10 mesh sieve possesses 10 openings per inch in both sides.
• The stainless steel mesh used in 20 mesh sieve has 20 holes per inch.
• The wire mesh stainless steel used in 50 mesh sieve has 50 openings per inch.
• There are 60 holes per inch for the steel screening mesh of 60 mesh sieve.
• The ss screen of 100 mesh sieve has 100 openings per linear inch.
• There are 120 holes per inch for the stainless steel wire screen of 120 mesh sieve.
• The mesh screen of 325 mesh sieve has 325 openings per inch.
• The steel screen of 400 mesh sieve possesses 400 holes per inch.
• The ss screen of 500 mesh sieve has 500 openings per linear inch in both directions.
• And so on.

Usually, the larger the mesh number, the more the quantity of holes per inch, the smaller the screen opening size, the smaller the particle that can pass through the mesh. We know that there is a function between mesh count, opening size, and wire diameter. So the size of the openings is also related to the size of the wires in the mesh. The thicker the strands, the smaller the openings that a particle can pass through.

Mesh number = 25.4 mm / (wire diameter [mm] + opening size [mm])

Wire mesh size is not only be assigned a mesh number, but also be denominated in mm or microns. So we can say the needed woven wire mesh sieves according to hole size in mm. For instance, 1 mm sieve, 2 mm sieve, 5 mm sieve, etc.

Micron size of laboratory test sieves can also be used to figure out what kind of mesh screen you need for your mesh sieve set. For example, we can say we need stainless steel mesh sieves, like 1 micron sieve, 10 micron sieve, 50 micron sieve, 63 micron sieve, 75 micron sieve, 100 micron sieve, 250 micron sieve, 850 micron sieve, and so on.

A micron is defined as one-millionth of a meter. Micron is the measure of length, and is most frequently used to describe particle size. It typically refers to the nominal opening size. For instance,

• The nominal opening size is about 0.02 mm for the stainless steel fine mesh screen of 20 micron sieve.
• The hole size is 0.04 mm for the stainless steel mesh sheet of 40 micron sieve.
• The aperture size is about 0.063 mm for the metal mesh screens of 63 micron sieve.
• The opening size of woven wire mesh used in 75 micron sieve is approximately 0.075 mm.
• The hole size of stainless steel filter mesh used in 100 micron sieve is 0.1 mm.
• The aperture size of mesh screen used in 500 micron sieve is about 0.5 mm.
• And so on.

It’s the mesh which has 40 openings per inch in both directions.

Its wire diameter can be 0.254 mm. If so, opening size will be 0.38 mm, and micron size is 380.

Therefore, particles over 0.38mm will be trapped above the woven wire mesh, while the others will pass through the steel mesh screen.

If there are 80 openings across one linear inch for a stainless steel filter mesh, then we say it’s 80 mesh size.

If so, hole size may be 0.18 mm, and then micron size will be 180.

As a result, particles larger than 0.18 mm will be trapped above the 80 mesh sieve, and smaller particles can pass through the sieve filter mesh.

A 200 mesh sieve is the laboratory test sieves which has a 200 mesh woven wire mesh. So what does 200 mesh mean?

• It means the fine mesh filter has 200 openings per inch in both directions.
• We can also figure out that the aperture size is 0.0737 mm from the mesh screen size chart. So its micron size is about 73.
• Moreover, particles over 0.0737 mm cannot pass through 200 mesh sieve, but the others can.

If the mesh screen of stainless steel test sieve has 4 openings per linear inch, then we say it’s a number 4 sieve.

According to the mesh screen size chart, we can figure out that the opening size can be 4.75 mm or 5.16 mm.

So there will be 4 numbers of 4.75 mm or 5.16 mm holes present within one inch length of mesh screen.