During isobaric PVT measurements, the volume is determined at constant pressure as a function of temperature. The material is filled in at melting temperature and heated up to the starting temperature. Then a constant pressure is applied. Cooling is started and controlled to a constant cooling rate. During cooling, the volume is recorded as a function of the temperature. Afterwards, the system heats up again fully automatically and sets the next pressure level. In this way, any number of isobars at different pressures can be measured fully automatically with a single barrel filling.

GÖTTFERT offers the possibility to perform isobaric and isothermal PVT measurements according to ISO 17744 with the capillary rheometer add-on "PVT" or with the stand-alone instrument PVT 500.