SU493687A1 - Device for calibrating gauges - Google Patents

Description

The invention relates to the field of instrumentation.

The known devices for calibrating gauges do not provide sufficient accuracy when calibrating gauges over high-temperature rarefied gas.

In the proposed device, a large-volume chamber is made in the form of a pipe with a diameter greater or equal to the mean free path of gas molecules, through which graduation is carried out, equipped with a heat removal element, located between the gas preheater and the control manometer.

Due to this, the accuracy of calibration for high-temperature rarefied gas is improved.

When studying the effect on a product model of pulsed high-temperature gas jets in a vacuum on the transfer function of a manometer, in addition to the factors, the effect of yush on them at high pressures is eh, e, and the effect of temperature transpiration, for example, the effect of a change in gas temperature in the gauge of time. The dryness of this effect is that if two vessels are connected by a tube with a radius comparable to the mean free path of the gas molecules and are at different temperatures, the pressures in these vessels are not equalized, and the greater the difference in temperatures and less tube radius.

The drawing shows the proposed device.

The device consists of a large volume Chamber 1, made in the form of a pipe with a diameter greater than or equal to the mean free path of the gas molecules for which the graduation is carried out, preheater 2 gas and

a test gauge 3 connected to the cooled part of the chamber, the small volume chamber 4 with a thermostat 5, in which the calibrated pressure gauges 6 are installed, the membranes 7, hermetically separating the Yush, the chambers,

percussion mechanism 8 for rupture of the membrane, a vacuum pump connected to each chamber through valves 9 and 10 of the heat sink device 11.

The device works as follows.

When the vacuum pump is turned on, the valves 9, 10 are opened and the gas is pumped out of the chambers to the required vacuum program, which is measured by a control manometer. After that, the valve 10 is closed, the gas heater is turned on, and devices supplying coolant to the heat sink and thermostatic fluid to the thermostat. When the vacuum pump evacuates the pressure in the chamber

a small volume to a high vacuum controlled by one of the calibrated pressure gauges, the valve 9 is closed. After the gas is heated in a high-volume chamber in the area of the membrane to the required temperature, a command is simultaneously sent to the percussion mechanism to break the membrane and the measuring device, which records the signals from the calibrated gauges in time. In order to characterize the manometers at other pressures and temperatures in KaiMepe of large volume, a new membrane is installed in the device each time, and the whole cycle is repeated.

Subject invention

A device for calibrating gauges containing a large-volume chamber with a gas preheater and a control manometer, a small-volume chamber with a thermostat in which calibrated gauges are installed, a membrane, hermetically separating the yush, a chamber, a percussion mechanism for breaking the membrane and a vacuum pump connected to each chamber through the valve, distinguish; e with the fact that, in order to improve the accuracy of high-temperature calibration

sparse gas, in it a large-volume chamber is made in the form of a pipe with a diameter greater than or equal to the mean free path of the gas molecules through which the graduation is carried out, equipped with a heat sink w, it

element located between the gas preheater and the control pressure gauge.