For efficiency in operation, injection molding production with large and heavy molds requires high heating capacity on the one hand, and correspondingly high flow rates in the cooling channels on the other hand. The new Wittmann Tempro plus D L120 temperature controller is the perfect solution for such tasks.
First of all, this temperature controller offers a maximum heating capacity of 36 kW, a value which ensures an optimal heating time for the mold from both the technical and the economical point of view. This is of special importance whenever very fast heating is necessary, for example after a mold change.
The heat accumulated in the hot steel of the mold plus the additional heat input from the melt caused by the injection molding process must be extracted again from the mold circuit as fast as possible via the cooling channels. This is the only way to establish a homogeneous heat transfer inside the mold, which benefits the entire process. To create ideal conditions in this respect, the Tempro plus D L120 is optionally equipped with a new frequency-controlled pump. This pump model, known as the SpeedDrive pump, comes with an output of 4 kW, can handle a maximum flow rate of 300 l/min and generates a maximum pressure of 5 bar. With the SpeedDrive pump, users are able to set the correct parameters for further process regulation – motor speed, flow rate, pump pressure and differential temperature. An approach which makes a vital contribution to process stability. Automatic adjustment of the parameter settings within a certain tolerance margin also optimizes the uptime of the equipment in production. Using a SpeedDrive pump can be seen as a synonym for energy-efficient pump operation, since it is generally sufficient to operate the pump under partial load to comply with the selected parameter settings.
New Wittmann temperature controller: the ultimate power package
The development of the new Tempro plus D L120 was prompted by increasing tendencies on the market towards the necessity for fast heating of large molds, while simultaneously providing the subsequently required high cooling performance. After all, such a solution must also contribute to optimizing the cycle time. Consequently, the cooling function of Tempro plus D L120 has taken the form of an extremely effective direct cooling system for the mold water. In this type of cooling system, the use of conventional magnet cooling valves would involve certain risks, since the timed cooling sequence would inevitably cause pressure surges as well as fluctuations in the temperature and system pressure, which could even cause cavitation of the pump. To eliminate such failures once and for all, Tempro plus D L120 has been fitted with a ¾-inch proportional cooling valve with a flow rate coefficient of 100 l/min. This valve operates with a step motor which continuously opens or closes the valve sequentially to maintain constant temperature control and exclude all possible malfunctions. Finally, this valve has proved to be completely maintenance-free in practice, which must be attributed to its special design.
The following is an example for the phenomenal cooling performance of Tempro plus D L120: a differential temperature of 60 °C between mold water and cooling water is the result of an extremely high cooling performance of 175 kW!
As an option, a stainless steel vortex flow measurement device is available for the temperature controller, with a measurement range from 20 to 400 l/min to cover all conceivable applications.
