How to choose a sieve.

Sieving, sifting, separating, screening ? How to choose the correct system for you. Product sieving is now an essential requirement in nearly all industries. To obtain a quality-controlled end product not only requires diligent ingredient choice but careful handling and processing. Removal of any substandard or unwanted foreign matter is therefore a prime requirement. A SIEVE is a SIEVE, is a SIEVE, a statement often used by the unknowing - but not all sieves are created equal. Choosing a sieve can be a daunting task, not only are there a number of manufacturers purporting to provide the answer to your needs but also the choices of differing types, sizes and configurations make things even more bewildering. Do you choose new or second hand, round or square, buy through an agent or from a manufacturer? Can the supplier support the sale with spares back up, can they support the sale with engineering back up, can they supply all those necessary items to ensure that you can connect your existing or new equipment to the sieve? Is the unit in a hazardous area? All considerations when making that purchasing decision. Then there is the consideration of price, too expensive – are you getting value for money, too cheap - is the quality of the product suspect, will it last? Choosing a sieve. It sounds obvious, but the first consideration is ‘what is the sieve to be used for’. This fundamental consideration is so often overlooked: • Check/police sieving • Grading / Separating • Linear sieving • Ultrasonic sieving • Laboratory analysis • R & D Ensuring the requirement is correctly specified will narrow down the choice process. Assistance is always available from Farleygreene and test, trial equipment may be necessary to obtain the best option. Tests or trials can be carried out on site or within a test facility. Types of sieves available. Check sieving. Check sieving, policing sieving, ‘I just want to get any lumps out’ are terms, which relate to sieving to prevent contaminated material being transferred to the next part of the process eg. Low to high risk areas. Normally a single mesh screen is fitted to the machine, the good material passes through and any larger unwanted material is retained above. This is probably the most straightforward arrangement for sieving and in general terms the most popular system in use. Check sieving can be carried out in many differing configurations. The simplest being, to position a ‘Slimline 550, 950, 1250 or 1550’’ unit directly into the flow line of the product, at the beginning or at the end of the process dependant upon the need. These machines are designed with low height and provide easy retrofitting into existing process lines, taking up little space and avoiding the need for major installation upheaval. Alternatives include the incorporation of a bag ‘rip and tip’ station, allowing users the facility to unload sacks of material directly into the process. The ‘rip and tip’ station includes a waist height table to open the bag a course griddle to prevent the sack damaging the sieve mesh, a ’Slimline’ sieving machine and connection to the next part of the process. Conveying systems can also be included, if necessary – screw elevators/conveyors, flighted elevators/conveyors, pneumatic, vacuum or blowing systems, - almost any arrangement. For those requiring a more versatile machine, the ‘stand alone’ units are an ideal arrangement, providing users with a mobile sieve that can be positioned wherever the need is. More suitable for the batch user, these machines are available from 300 diameter up through 450, 600, 700, 800, 900, 1000, 1200 and 1500 diameter, each available with an array of accessories to make sieving simple and effective. Where large quantities of material need check sieving a ‘Rotary’ or ‘Centrifugal’ type sieve may be the better option. This type of unit can

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