# CSC Scientific Blog

For several years, people in the test sieving business have been grousing about the difficulty of making sure that a test sieve certification is what they need. Anyone who is working with close tolerances in the smaller particle sizes, like 300 microns and smaller, have serious issues in matching results from test sieve to test sieve.

Sieve testing, as I have stated many times, is the Cinderella of particle size analysis because it delivers more value than expected from something that’s so easy to use and relatively inexpensive. However, the problem with standard sieving techniques using wire mesh sieves is that they begin to exhibit accuracy problems in the lower micron sizes.

# Break the Curse of Particle Size Calculations

Every now and then I’ve had to calculate the results of a sieve test: I’d get the sieves and sample loaded on the shaker,  run the shaker, then realize I’d have to start over because I forgot to get the empty weight of each sieve. Or I’d have to carefully brush out the sample onto a balance.

Chapter One:

Jim’s life was dull. So, so dull. He spent his days surrounded by piles of sieves – his glamorous job was to calculate the ratio of particles left in the sieves of each stack after a sample of his company’s product was run through the stack using a sieve shaker. It was a job much like the one his cousin Hiram had, although he seemed to remember hearing that Hiram had found an easier way to do it.

Visitors to our web pages often arrive with the question, “What is the Function of a Sieve Shaker?

The simple answer is “to expose the particles in a sample to all the openings in each sieve in a stack”. A sieve stack is the result of fitting each sieve to be used in a given particle size analysis into the one above. The sieve with the largest mesh holes is at the top with each subsequent sieve of a tighter mesh size than the one above it.

Sieves make understanding the world around us not just possible, but also easier.

And with the advancement of sieves, not only are we able to separate dry particle, but also sift molecules from fluid as well. With molecular sieves developed by MIT, we can now strip a molecule’s individual parts gives us a better understanding of how things come together and work, such as diseases or even DNA.

The primary purpose of a sieve shaker is to provide motion to a sample in a test sieve.

An effective sieve shaker creates a motion that presents all the particles to all of the sieve openings and assists particles in passing through. This requires both rotary and vertical motion.

This process seems simple enough, but let's not be taken in.

The relative value of a sieve certification process vs a sieve calibration has perplexed me for a long time.

I'll bet that most of you have experienced the shock of walking on a thick wool rug on a dry winter's day and getting zapped out of your reverie when reaching for the metal door knob.

The same process of static electricity generation can play havoc with your sieving process.