THERMOSTAT AND PYKNOMETER FOR PRECISION MEASUREMENT OF LIQUID DENSITY Russian patent published in 2015 - IPC G01N3/04 

FIELD: instrumentation.

SUBSTANCE: invention relates to inspection equipment, namely, to devices for research of liquid density in a wide range of temperatures by pyknometric method. A fixed thermostat is a long sleeve with a pyknometer installed inside, fixed on a vertical massive stand. The sleeve with the pyknometer is inserted into a wide thermostat pipe with circulating thermostatting liquid, supplied and drained via nozzles, which in its turn is installed into a heat-insulation pipe with a thick layer of porous asbestos and a heating cylindrical furnace. All system is fixed on the platform. A two-capillary pyknometer includes a loading bunker, calibrated metering capillary tubes and a working chamber comprising two compartments - upper and lower ones. To a cone-shaped bottom of the upper compartment a system is fixed in a vacuum-tight manner from several serially connected reservoirs of small volumes (~1 cm³), and a thin-walled tube is axisymmetrically entered into the upper end of the lower compartment with thermocouples, working seams of which are arranged accordingly in the centre, near the opposite walls and near the bottom of the lower compartment with the investigated liquid, for precision monitoring of true temperature of the investigated liquid.

EFFECT: temperature range (interval) of density measurement increased several times with high accuracy of density measurements, considerable simplification of pyknometer design and its operation, provision of balanced thermodynamic conditions of density measurements of investigated liquids in high static vacuum, without further opening of a pyknometer and vacuum disturbance in it, in a wide temperature range of measurements, making it possible to perform both precision control of true temperature of investigated liquid and also possible temperature gradients inside samples; multiple increase of research labour efficiency and considerable saving of highly pure substances during precision measurements of temperature dependence of liquid density in a wide area of temperatures.

2 cl, 2 dwg, 1 tbl