SU1404849A1 - Device for measuring pressure change - Google Patents

Abstract

The invention relates to a measurement technique and makes it possible to increase the accuracy of measuring the change in pressure. Liquid differential. pressure gauge 1 is connected by its Ko,: i.e., to chambers 2 and 3, in which bellows 5 and 7 are dispersed. Through an additional valve 11, bellows 5 and 7 are connected to the source of measured pressure of tank 12. Deviation of pressure in tank 12 from nominal value it is fixed by a pressure gauge 1, the tubes of which are interconnected by a second second terminal: 1 valve 8. A single reference, 1 pressure in the chambers is set, 1 is mounted when the nose is bluish. p. - to the nominal opening of the ventil.chs 811. C.-1fop 7 is made with an effective area that is the same as that of the bellows S, but with less than V than it, rigidity. 1 and.h.

Description

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The invention relates to mechanical engineering, in particular to the test section.

The aim of the invention is to improve the measurement accuracy.

The drawing is a schematic diagram of a device for controlling pressure.

The device consists of a differential liquid manometer 1, connected by its opposite knees to a closed chamber 2 of small section and

devices to the new nominal value of pressure in tank 12, by performing the listed operations again.

The advantage of the invention is to ensure constant measurement accuracy and sensitivity to pressure drops near their nominal values in a wide range of measured pressures.

The proposed device is especially effective in determining the total non-closed chamber 3 of a larger cross section, the hermeticity of closed objects that are symmetrically divided into cavities A and B by force 4 and bellows 5 and cavities C and D by piston 6 and bellows 7.

Differential pressure gauge elbows 1 communicate through valve 8. Valves 9 and 10 are designed to equalize the pressure in the chambers and separate the cavities A and B, C and D, respectively.

The valve 11 connects the device to the tank 12 with controlled pressure.

Before starting the operation of the device, the valves 8-11 are sequentially opened and a single pressure equal to the nominal pressure controlled in the tank 12 is established in all the chambers.

Then close the valves 9, 10 and 8, leaving the valve 11 open.

The subsequent deviation of the pressure in the tank 12 from its nominal value with a given accuracy and sensitivity, due to the difference between the stiffness of the bellows and their effective flat under excessive pressure.

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Claims (1)

Invention Formula A device for measuring pressure change, containing a liquid differential meter with pressure sensing first and second tubes, a source of measured pressure and first and second shut-off valves, characterized in that, in order to improve the accuracy, two chambers are introduced into it, first and second, with the first and second bellows arranged in them, as well as two additional valves, the bellows cavities being connected via the first additional valve to the measured pressure source, and through the first and second ventilation l are respectively connected to the cavities of the first and second chambers, wherein the first and second chambers are connected respectively to the first and second sparingly, the differential gauge will be fixed by the differential pressure gauge tubes, the tubes are connected rum 1. between myself through the second additional If necessary, control deviations ventil, and the effective area of the first pressure having a different nomi-bellows value is greater, and its stiffness is MCHbnje, They are re-tuned at the second bellows. devices to the new nominal value of pressure in tank 12, by performing the listed operations again. The advantage of the invention is to ensure constant measurement accuracy and sensitivity to pressure drops near their nominal values in a wide range of measured pressures. The proposed device is especially effective in determining the total leakage of closed objects, with under pressure. Invention Formula A device for measuring pressure change, containing a liquid differential meter with pressure sensing first and second tubes, a source of measured pressure and first and second shut-off valves, characterized in that, in order to improve the accuracy, two chambers are introduced into it, first and second, with the first and second bellows arranged in them, as well as two additional valves, the bellows cavities being connected via the first additional valve to the measured pressure source, and through the first and second ventilation l are respectively connected to the cavities of the first and second chambers, wherein the first and second chambers are connected respectively to the first and second differential meter tubes, tubes connected