Mesh Size

(not verified)
Posted in: , on 21. Sep. 2003 - 17:41


I have a simple yet important querry-

If we have to replace a wire mesh used for sifting

with a SS perforated screen, how is the diameter of

the screen selected so as to obtain the same powder

characteristics while using the wire mesh.

For eg If I want to replace 20# how much mm perforated

sieve should I use?

With thanks and regards,

Deepak Varma

Re: Mesh Size

Posted on 22. Sep. 2003 - 07:32

Hello Mr. Deepak,

I believe, you have the published data indicating the sieve number vrs. the aperture size. So, you can choose the perforation size accordingly.

However, the screen cloth made of wires will have more screening area compared to perforated screen. This is in context of screening net space per centimeter square or inch square. The perforated screen has comparatively less net screening area, and hence its screening function will become less effective.

In general wire cloth screens are good for fine screening where particle size is small enough not to damage the wire. The perforated screen will be good when it has to deal with bigger size of particle (lumps) which can damage the wire.


Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyor.

Email :

Tel.: 0091 (0)20 5882916

(not verified)

Mesh Size

Posted on 23. Sep. 2003 - 12:53

Hello Mr. Gulani,

Thanks for your reply.

I dont have any supporting data regarding comparative

values of mesh size and apperture size as you mentioned.

The only value I am having is a British standard specification

stating that a 20# wire sieve should have an optimum

apperture size( diameter,should be) of 0.84 microns.

But this pertains only towire mesh .

What about perforated screens? How much mm perforated

screen should I use to replace a 20# wire mesh?

Hoping you would enlighten me further,

With Thanks and Regards,

Deepak Varma

Re: Mesh Size

Posted on 23. Sep. 2003 - 05:51

Hello Deepak,

Presently, I have only following data about USA Tyler screen :

Screen number3, Opening size 0.371 inch (6.68 mm),

Screen number4, Opening size 0.185 inch (4.70 mm),

Screen number6, Opening size 0.131 inch (3.33 mm),

Screen number8, Opening size 0.093 inch (2.37 mm),

Screen number10, Opening size 0.065 inch (1.65 mm),

Screen number14, Opening size 0.046 inch (1.17 mm),

Screen number20, Opening size 0.0328 inch (0.84 mm, i.e. 840 microns),

Screen number28, Opening size 0.0232 inch (0.59 mm, i.e. 590 microns),

Screen number35, Opening size 0.0164 inch (0.42 mm, i.e. 420 microns),

There could be different standards for the above, but possibly there may not be remarkable difference amongst them for mentioned screen size number.

Coming to your specific query, as per my information you will not get perforated screen for screen size # 20 as it is very fine (very small) opening, and it may be difficult to make such screen.

If need be, please refer to screen manufacturers for more specific information.


Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyor.

Advisor / Consultant for Bulk Material Handling System & Issues.

Email :

Tel.: 0091 (0)20 5882916

(not verified)

Mesh Size

Posted on 26. Sep. 2003 - 02:44

Hello Gulani,

Thanks for your reply.

The info you have provided is almost what I am looking for.

As per it,Screen 20 should have an apperture of 0.84mm as


It matches the data I am having for the apperture size

required for a 20# wire mesh which states 0.84 mm + - 5%.

There is minor difference between standards.For eg in

US TYLER the next screen is 28 while the one I am having

mentions 30.

The point remaining is that effective screening surface reduces

for perforated screens for a comparative wire mesh.

So what mm should I use to compensate this loss?

Looking for further enlightment,

With thanks and regards,

Deepak Varma

Vibrating Screen Mesh

Posted on 2. Oct. 2003 - 04:01

Hello Mr. Deepak Varma,

Concerning your inquiry about comparative production between wire steel mesh and punched ss sheets:

-the selection under 1 mm. with punched sheets is very difficulty

-the free screening surface is reduced comparated with wire steel mesh

If you want to replace the wire steel mesh for wearing lifetime problem and you like to improve prouctivity please consider the elastic polyurthane anti clogging slotted mesh (realized with water jet process)

Hoping to help you in your choice



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