Gravimetric dosing is used wherever extremely high dosing accuracy is required. Sodimate’s loss-in-weight feeder systems achieve a dosing accuracy of +/- 0.5%
However, users should first consider whether this high dosing accuracy is actually necessary for their process, the volumetric dosing systems from Sodimate already achieve a dosing accuracy of +/- 3%.
In most cases, the powder is fed into the weighing container via a feed screw from a silo, if necessary also from a big bag emptying and dosing station or a sack dump.
The weighing container is built on a solid, vibration-free steel frame. The weight is recorded with 3 robust load cells or with a stable weighing platform.
In principle, it is also possible to place the Big Bag emptying and dosing station on load cells and do gravimetric dosing.
The weighing container is equipped with 2 level indicators (high level, low level) that regulate the product supply. The added amount is approximately 10 times as high as the desired weighed dosing amount with the aim of keeping the blind phase during weighing as short as possible
The functional principle of gravimetric dosing is based exclusively on a certain (product) mass loss in a certain time. There are no other factors that would play a role. Loss-in-weight feeders do not use a zero reference as the basis for calibrating the feeder output rate, they only use mass loss over time.
The mass loss principle provides an extremely accurate and highly reliable method for continuous weight dosing, combining the accuracy of a static measurement with the flexibility and power of a continuous dosing system.