Sensor Technology Ltd: Cold extrusion is playing an ever greater part in recycling of waste plastic, and the Department for Business and Enterprise is sponsoring research into development of the machinery necessary for such work. Engineers at Bradford University have built a pilot plant and are running a series of trials with different processes, feed plastics, additives, and final products. Leader of the project, Dr Raj Patel explains: “We started out comparing cold extrusion and warm extrusion, in which the material is heated prior to processing, and quickly realised that cold extrusion was more suited to recycled plastic. Our process now is to granulate the recycled materials to a consistent size, mix in binders as appropriate to basically, glue the particulates back together, and cold extrude it into sheets or blocks.” “The extrusion process is the critical stage, so we are monitoring many parameters relating to this.” The single most important parameter is torque in the extruder drive. This indicates the force required to process the material and hence both the power requirements of the drive and the viscosity of the plastic. It is measured using a digital TorqSense torque sensor, which uses Surface Acoustic Wave techniques to provide a non-contact method of monitoring continuous rotary torque, allowing accurate modelling of the instantaneous load changes. ...

The semiconductor manufacturer PREMA Semiconductor GmbH offers in-house development and production of customized, analog and mixed-signal ICs, together with standard ICs for specific applications (ASSPs), a new product segment. The applied ModuS U6 process has been enhanced continuously. NPN and PNP transistors with smaller structures are now available as well as metal-metal capacitors with a high sheet capacitance and CMOS transistors. The high voltage bipolar components allow circuit designs for supply voltages from 1V up to 100V in consumer applications and in the industrial and automotive range. Sensors like photo diodes and hall elements together with highly sensitive instrumentation amplifiers can be integrated into one chip as well as high voltage transistors and CMOS switches. Digital circuit parts can be realized with small-sized CCL gates. ...