Piovan's novelties
The Italian Piovan is a leader in quality in the plastics material processing sector. The company has completed a range of auxiliary machinery to respond to any requirement in the specific areas of injection and blow moulding, extrusion, pet preforms and optical applications. Now is introducing all over the world its new product and technologies in example new series of HR dryers, masterbatch doser MDP 2G and chillers.
Piovan`s innovative gravimetric doser for masterbatch MDP 2G ensures precise dosing and constant blends over time, in the injection and blow moulding process and in extrusion applications. The loss-in-weight gravimetric technology allows constant control of the dosed material and high precision. It is available in the single and twin-station versions; its throughput ranges from 0.035 to 138 kg/h.
The MDP 2G gravimetric doser can be equipped with one or two dosing stations, connected with a weighing cell which sends to the control system a signal proportional to the weight of the dosed material. At very short intervals, the control checks the variations of throughput and automatically corrects them in line with the set value, adjusting the revolution speed of the screw. The unit constantly keeps the set and guarantees high dosing reliability.
The new Piovan`s gravimetric doser ensures immediate start-up, with no waste of time. It is sufficient to set the percentage to be dosed, without carrying out any calibration or dosing test. The unit starts immediately to dose activating the quick start-up procedure. The important function is also the possibilities of safe and quick production shift. The dosing station can be rapidly detached with no need of tools. For cleaning operations, it is possible to use the handy device for material discharge.
Another novelty of Piovan is the newly developed HR dryers which represents latest evolution in the drying field. The models HR 50, HR 100, HR 150 and HR 200 provide an airflow ranging from 50 up to 200 m3/h and keep the Dew Point value constant. By adopting the honeycomb desiccant rotor technology, the HR Series is able to ensure maximum energy efficiency and versatility of application in small and medium productions.
The HR dryers are equipped with two side channel blowers, one dedicated to the
process and rotor cooling phases, the other to the regeneration phase. The drying
process is independent from the ambient conditions, with consistent Dew Point,
with values ranging from -25°C to -50°C.
The rotor solution adopted by the new Piovan Dryers HR Series allows the operator to effectively intervene on the process parameters, and to have at his disposal a flexible drying system which can be adjusted to the real production conditions. The rotor carries out an optimal moisture-molecular sieve exchange, with performances of 35 percent higher than the desiccant tower dryers with the same floor dimensions.
Both the continuous functioning cycle and the rotor`s design ensure no deterioration of the molecular sieves and higher duration of the absorption material.
The HR dryers can be combined with drying hoppers with a capacity from 100 to 600 dm3. In typical configurations, the drying hopper is installed on the processing machine or beside it, or placed on a trolley. Both single-hopper and PTU multi-hopper versions are available; they are particularly compact and equipped with devices for advanced functioning which result into optimised energy consumption.
In the PTU multi-hopper configuration, the dryer can be connected with 8 drying hoppers maximum, all of which are equipped with a dedicated electronic control. Moreover every single drying hopper is supplied with an independent heating chamber for drying different materials at different temperatures.
The PTU system can also include an integrated vacuum unit, for loading the material into the drying hoppers of the trolley. In the multi-hopper version, the dryer includes the Drying Control function. According to the data set by the operator, the electronic system continuously checks the loading times of the drying hopper and the drying times, and signals any anomaly. In this way, it ensures optimal treatment of the material being processed.
Worth to mention is also the new CHW water-cooled series. It includes a wide range of chillers able to satisfy the cooling requirements of most applications of the plastics industry, in particular in the PET preform sector.
With a cooling capacity ranging from 100 kW to 670 kW, the CHW models are ideally suited for centralised installations, especially for applications characterised by quick mould changes or where no glycol is permitted in the cooling circuit. Everyone ought to know that condensed cooling is usually performed by means of an external cooling tower, which optimises performance and considerably reduces energy consumption. In case of installations in climates where the temperature may drop below 0°C, a glycol make-up kit must be considered.