A sieve shaker is a machine designed to hold and agitate a stack of sieves for the purpose of separating a soil or other granular material sample into its component particles by size. The stack of sieves is composed of sieves of different sizes. The one with the largest openings is on the top while the sieve with the smallest openings is on the bottom with a solid tray beneath to catch the smallest of the particles. The sample is placed into the top sieve of the stack, and as the sieve shaker agitates the sample, the individual components sift through each of the sieves in turn with each one retaining particles of a successively smaller size.
Soil analysis is an important tool for geologists, agronomists and civil engineers. It provides a great deal of data about a soil and how a particular soil will behave under certain uses, stresses and conditions. Information about soil compaction, settling, drainage, age and origin can be determined from soil analysis and a sieve shaker makes this process easier and more precise. By automating and standardizing sieve tests, meaningful comparisons can be made between soil samples.
While there are several manufacturers of sieve shaker machines and each has its own unique design, certain features are common to nearly all machines of this type. Most sieve shakers will hold a varying number of standard-sized sieves — usually as many as ten although some will hold more. Sieves can be standard height or half height, and most machines are capable of holding sieves of varying diameters as well. A stack of sieves can contain a mix of standard and half height sieves, but all the sieves must be the same diameter.
Agitation patterns can vary from machine to another. Some sieve shakers use a circular motion, moving the sieves in a circle but without rotating them. Vibration is another method and a third method incorporates a vertical element with a lateral shaking movement like a chef tossing food in a frying pan. Some sieve shaker machines are capable of more than one of these patterns.
All sieve machines have electric motors. Some models are portable, running on battery power. Controls tend to be relatively simple and include timers and shaker motion controls. Most sieve shakers accept any manufacturer's sieve although some can use only their own sieves.
