Segmented mould temperature control at the highest level
The new integrat 80 multi-circuit temperature control system is being presented by gwk (gwk Gesellschaft Wärme Kältetechnik mbH of Meinerzhagen, Germany) for the first time to the public at K 2016 (hall 10, stand J39). The successor to the integrat plus boasts many technical innovations designed to meet the requirements of the fabricators for higher availability, more comprehensive process monitoring and energy-efficient operation. The highlights include constant coolant control, which is not susceptible to contamination, with a newly developed throughput measurement system up to 140 °C which functions without any moving parts, as well as frequency control of the sealless, magnetic-drive, stainless steel pumps if required. The new controller, equipped with a fast 32-bit processor, communicates with the operator via a central 7-inch touchscreen, on which the key parameters of up to 24 temperature control circuits are adjusted and monitored.
What has not changed are outstanding features such as the separation of the hydraulic circuits from the electrical components, the high level of flexibility and the compact design. To these have been added the spatial separation of the convenient controls from the load electrics and the use of IE3 motors on the magnetic-drive, stainless steel pumps, as well as the possibility of now operating up to 24 temperature control circuits via a single interface to the fabricating machine. Another new feature is the possibility of extending the temperature control system to a maximum of 96 temperature control circuits by means of four-way distributors for each temperature control module, with the throughput volume and the temperature of the circulating medium shown on the central display.
"With their compact design, low installation costs and the ease of replacement of individual modules, multi-circuit temperature control systems such as the new integrat 80 offer many advantages over individual units," explains Helmut Gries, Director of Sales and Marketing. "Especially for the segmented temperature control of large moulds, they achieve optimum results." The division of the injection mould into various temperature control zones, dependent on the partial heat induction from the moulded part, forms the technical basis for this. For example, where a lot of material is accumulated, more heat has to be conducted away per time unit than is the case for thin-walled sections of the mould. Customised control with the possibility of setting a predefined, independently controllable and adjustable operating status for each temperature control circuit with the aid of a separate pump, ensures a homogeneous temperature profile.
"The new integrat 80 is more powerful than its predecessor. Each circuit now has a heating output of 9 kW and a powerful 60-litre pump," reports Gries. "Up to 6 units can be housed on a single stand with just one central coolant connection and a single power supply point. This basic assembly with the central control unit can be extended by the addition of up to three more, individually configurable stands, distributed around the machine. This combination results in up to 24 independent and fully featured temperature control circuits, which can be operated and monitored via a single control unit in the central control cabinet." The subassemblies for pumps, heaters, cooling and water regulation are integrated into individually lockable and replaceable hydraulic units, while the central, two-part control cabinet contains the load electrics and the microprocessors.
In addition, each temperature control module can be equipped with vts four-way distributors, as tried and tested in gwk's teco-series individual temperature control units. "This smart distribution system enables the monitoring of the throughput volume and temperature of the parallel consumer circuits. It guarantees by means of manually adjustable valves the equalisation of the the parallel hydraulic circuits, thus ensuring the necessary throughput volume with channels of varying geometry and dimensions. Thanks to the constant monitoring of the process data with adjustable tolerance bands, the reproducibility of the quality of the moulded parts can be guaranteed, at least from the perspective of mould temperature control," says the Director. "Limits can be set for throughput volume, return temperature and differential temperature for each circuit, and the operator can be alerted if these are exceeded. A total of four subsidiary circuits can be configured for each circuit, so a fully equipped integrat 80 can monitor a total of 96 circuits."
Another option which makes a significant contribution to the energy efficiency of the system is the frequency control of the pumps on the basis of the temperature difference. On this point, Ralf Behr, Product Manager for many years at gwk and significantly involved in the development of the new multi-circuit temperature control system, says: "Pump frequency control takes into account the fact that the energy input or extraction of the production process causes a larger or smaller temperature difference in the heat transfer medium, depending on power output. As the temperature difference increases, the pump frequency is turned up and greater power output is required of the motor. At lower process output, the temperature difference in the heat transfer medium becomes smaller and the pump speed and hence the power consumption of the pump motor are reduced. In this way it is possible to adjust the operating point of the pump to match the process requirements, for optimum energy efficiency. The energy savings achieved in this way cover the additional costs of a multi-circuit system in no time at all."
The new integrat 80 also has a VNC-Server, enabling remote access to all parameter levels. "If the customer permits it and enables access, we are capable of accessing the system anywhere in the world," explains Dr. Michael Zaun, Director of Engineering and Production. "This is particularly useful when looking for faults, optimising settings or updating programs. This feature for the operation and monitoring of systems from remote locations is also very useful for customers. With the modulControl system module from our new controller family, integrat 80 is already fit to meet tomorrow's requirements that stem from the practical implementation of Industry 4.0."
Photo: The multi-circuit temperature control system in modular design integrat 80 for segemented mould heating and cooling at the highest level. (source: gwk).