The loss in weight dosing is a way to gravimetric (basing on weight) material feed. Such a process is carried out by devices that receive the material from above from the storage tank or via another transport device, and accurately dispense the material to the process with a specified yield. The dispensing element is, in this case, a screw (auger or helix), a double screw, a vibrating chute or a belt. The name loss-in-weight means weight loss and strictly determines the principle of work - the measurement concerns the material that is falling from the dispenser along with its delivery. Thanks to the fast control systems and the exact extensometer sensors, the device delivers the precise amount of material, both as a portion (kilograms) and in a continuous mode (kilograms per unit of time).
Properties of bulk materials
The characteristics and behavior of bulk materials differ with their physicochemical properties and the looseness measure. The critical parameters are bulk density, size, and type of grain, susceptibility to clumping, hanging, adhesion, and hygroscopicity. There is no universal way to dispense any material. Thanks to the use of various solutions and options, however, we can accurately dose even theoretically hard elements in administration.
High looseness characterizes the easiest to dose materials. The selection of the right screw for a screw feeder and drive parameters ensure an efficient way of feeding. For materials that are easily aerated and have properties similar to liquids, screws with a unique construction must be used. Materials with a tendency to clump and stick inside the tank require a separate agitator, which ensures that the screw is filled to a high level. Such an agitator can be built in a horizontal plane or additionally also vertically.
Brittle and easily damaged materials must be treated gently. For them, the most reliable choice is a vibro feeder. belt weighfeeders, which do not work on the basis of weight loss, are also ideal. Screw feeders, if correctly configured, may be suitable for this type of material, too.
We equip all our loss-in-weight dispensers with Flex programmable controllers. If you already have a feeder and would like to modernize it, we can implement it in your device. Flex is a modern control system equipped with a color touchscreen and extensive communication options. The significant advantage is the ability to modify the program and visualization, so you get a product "tailor-made."