The Bitzer Wiegetechnik GmbH is one of the leading suppliers of customised special constructions in the field of weighing technology. This customised project are constructed and realised by our experienced technicians and engineers.
The following is a list of examples from the field of special constructions:
The measuring principle of a weighfeeder corresponds to the principle of the belt weigher (weight and speed measurement). In addition to the actual “measurement programme”, control parameters are available, that allow a constant predetermined continuous material flow. The regulation of the dosing volume can be carried out by regulating the belt speed or the feeding components. The measurement program of the weighfeeder compares the actual feed rate with the set feed rate and regulates the dosing element. A variety of parameters allow the adaptation of the controller (PID controller) to optimise the controlled system. In practice, such weighfeeder can be used for recipe-controlled dosing of components from several silo cells.
With the help of a screw weighfeeder current flow rates and volume flows can be measured. For this purpose, a conventional screw conveyor is equipped with load cells and bearings. The continuous weighing indicator is fitted with a modified belt weigher programme, in which the conveying speed of the screw conveyor and the screw loading are continuously recorded. In addition to the display for the flow rates three further counter are available (e.g. batch counter, day counter, total counter), on which the indication of quantity is displayed in kg. Therefore, the screw weighfeeder are particularly suitable for internal check weighing as well as for loading and dosing.
A loss-in-weight feeder can be used for gravimetric dosing of bulk materials. In this construction, the actual flow rate of weight loss per unit of time is determined. A controller compares the actual feed rate with the set feed rate and regulates the dosing element. A loss-in-weight feeder consists of a weighing container which is installed onto the scale’s construction. An adjustable bulk material quantity is deducted from the container by using screw conveyor. A controller ensures the compliance of the constant flow rate. Relatively low flow rates at a very high dosing accuracy can be realised with this kind of scale. The loss-in-weight feeder is particularly suitable for dosing of small components such as vitamins.
Bulk Scales for liquids
Bulk scales for liquids are suitable for measuring the flow rates as well as for dosing of liquid containers. The functionality of this scale corresponds to the function of a scale for bulk materials. Depending on the medium, valves are used as shut-off- resp. dosing-devices instead of flaps. Bulk scales for liquids are equipped with special ball-cock valves in inlet and outlet, which ensure a high tightness even at low viscosities.
A belt-bulk scale is used when the installation of a conventional bulk scale is impossible due to confined space conditions. The high accuracy (legal for trade) of this construction conforms that of a bulk scale. A belt construction which is installed onto load cells is loaded with the help of a supply device. In the next step, the material is weighed and dispatched. The belt-bulk scale is suitable for weighing of bulk material and particularly heavy flowing material. The operation of the belt-bulk scale is possible by a weighing indicator or, as an alternative, by software solution. Moreover, this scale can be connected to different bus-systems (Profibus / Profinet) and can also be integrated into the process control system.