View showing Programmable Hydraulic Press ( 'Hot-Press' ) ready for use. The Hotpress consists of a commercially available heated press fitted with control equipment and software by Cardiff ETT. The complete package is able to heat and compress the work item in accordance with a timed profile decided by the user. The applied pressure can be made to vary with time, as can the temperature. The Proportional, Integral and Differential (PID) temperature control has full over-temperature protection on the upper and lower platens. Bespoke amplifier design for the Dowty Valve (Moog-type valve) used to control the hydraulics gives fast response (the driver would also find itself suited to higher-speed applications). The source for the hydraulic power is a standard electric compressor pack seen here to the right of the picture.




The control amplifier for the hydraulics is the grey box at the front of the assembly, with the Dowty Valve immediately to the right. Industry-standard Supervisory Control and Data Acquisition (SCADA) software is used. This allows a screen dialogue with the user.
Before the sample (work item) begins its heated compression period, a gradual application of heat and pressure ensures compliance with the sample manufacturer's specifications. The rates of increase of heat and compressive force are independently settable, as are the relaxation rates, keeping the sample safe from thermal shock.
A record of the temperature/pressure profile is preserved on-screen and can be saved to file for certification purposes (eg in the setting of adhesive and composite materials). The compressor unit is also under control of the software.

(Photos with kind permission of Carol Featherston. )