MELT PRESSURE MEASUREMENT AND THE LIKE

摘要

Melt pressure measurement probe (30; 30') for insertion through wall of melt-containing vessel has a pressure-deflectable end portion (33; 156) for contact with pressurized melt. Pressure-resistant securing means (50) fixes end surface in a non-flow obstructive relationship. Seal surface (54) on the probe prevents exposure of the melt to the securing means. Pressure detection means internal of the probe, responsive to deflection of the probe end surface to detect melt pressure, comprises a temperature-compensated capacitive sensor, one capacitor plate defined by end portion (33; 156) and opposite capacitor plate (66; 166) in the probe with a capacitive gap in-between. Electronic circuitry (126; 126') remote from the melt-exposed end, including circuitry (128) within the probe to generate a signal proportional to the capacitance, compensates for change of temperature on the capacitor to generate an output signal proportional to melt pressure.