RU2556323C2 - Damper for pressure gauges - Google Patents

Abstract

FIELD: instrumentation.

SUBSTANCE: invention relates to devices for pressure measurements of gas obtained by water decompounding in electrolysis-water generators. The damper casing has socket for pressure gauge and union for gas supply. The damper casing is divided by vertical partitions to three compartments. In each partition near the casing bottom a hole is made with diameter 2.0-3.5 mm, at that outermost compartments are filled with liquid, for example with water to the level of gas supply union. Casing and partitions can be made out of three coaxial pipes with different length. If for the damper filling the silicone or fluor organic liquids are used, the damper is also separating vessel to measure pressure of practically any corrosive liquids and gases.

EFFECT: improved tightness of the damper.

2 cl, 2 dwg

Description

The invention relates to devices for preventing overloading devices with a measured medium, and more particularly, to devices for measuring the pressure of explosive gas (hydrogen-oxygen mixture) obtained by decomposition of water in electrolysis-water generators (the term "electrolysis-water generator" according to GOST 2601-84, term No. 160). The invention can be used in other objects to protect gauge devices from overload and from damage by explosive and (or) chemically aggressive gases.

During the operation of electrolysis-water generators, it is not possible to completely exclude the possibility of an explosion of explosive gas in them due to a back strike or violation by the personnel of the operating rules. The explosion causes a pressure jump of 6-10 times lasting 3-5 ms. In this case, gas also explodes in the cavities of gauge devices (pressure gauges, sensors and pressure switches), damaging them. Therefore, to protect them, it is necessary to exclude the ingress of explosive gas into the device and extinguish pressure pulses.

There are many devices for protecting pressure gauges from short-term pressure overloads. But both of the above problems can be solved only by a damper block with a separator, adopted as a prototype [1]. It consists of a housing divided into two halves by a horizontal partition with a small diameter hole. A pressure gauge is screwed on one side of the partition to the housing, and an elastic cap is hermetically connected to the other side of the partition inside the housing. The internal volume of the elastic cap and the internal cavity of the sensing element of the pressure gauge form an enclosed space that is filled with liquid. The measured pressure is connected to the outer surface of the cap and tends to move the liquid from it into the internal cavity of the pressure gauge’s sensing element. The small diameter of the hole in the baffle slows down the flow of liquid, protecting the pressure gauge from pressure pulsations and from short-term overloads.

Such a damper is unsuitable for protecting pressure gauges in electrolysis-water generators, because in case of explosive gas explosion, the elastic, polymer cap is exposed to a hot blast wave (temperature above 3000 ° C) and quickly loses its tightness.

The design of the damper for gauge devices is shown in figure 1. Figure 2 shows a design variant with a housing and vertical partitions in the form of coaxial pipes. As can be seen from figure 1, the inner space of the damper housing 1 is divided by partitions 2 and 3 into compartments A, B and C. A pressure gauge or other gauge device 5 is installed in slot 4 of compartment C. Hydrogen-oxygen mixture enters through compartment 9 through nipple 9, whose pressure is measured. In the lower part of partitions 2 and 3 there are small (but not capillary) openings 6 and 7 - usually their diameter is 2-3.5 mm. Through socket 4 or nipple 9, water or other working fluid 8 is poured into housing 1. In this case, the liquid level in compartments A and C will be the same - up to nipple 9, and in compartment B it is only slightly higher than openings 7 and 8, because the liquid, blocking these openings, closes the air outlet from compartment B. The gauge device 5 is installed in the socket 4 after filling the fluid into the housing 1. With increasing gas pressure, part of the fluid from compartment A flows through the opening 8 into compartment B, compressing the air in it, and then through the hole 7 into compartment C, also compressing the air in it. Thus, in order for the pressure in the compartment with the manometer to increase to a certain level, it is necessary that part of the liquid flow from compartment A to compartment B, compressing the air therein to the same level. The pressure of the gas mixture during the operation of electrolysis-water generators changes relatively slowly, therefore, the decrease in the speed of the gauge device due to the time spent on the flow of fluid from compartment to compartment is almost imperceptible. However, with a gas explosion in the apparatus, the hole 8 limits the fluid flow rate so much that the pressure in compartment B does not have time to increase to the maximum permissible pressure gauge during the explosion. Accordingly, the pressure in compartment C below the pressure gauge does not increase above the permissible one. When the pressure decreases a few milliseconds after the explosion, the compressed air in compartment B squeezes the excess liquid back into compartment A. From compartment C, the air also squeezes out part of the fluid and the damper returns to its original state.

As the working fluid, you can use water and other fluids, in particular organosilicon and organofluorine. In the latter case, the damper is also a separation vessel for measuring the pressure of almost any aggressive liquids.

Figure 2 shows a similar damper, in which the casing and vertical partitions are three coaxial pipes (position numbers - as in figure 1). The top of the damper is made stepwise rather than flat, which makes it easy to check the tightness of welds 10 and 11.

The proposed damper, as shown by operating experience, is guaranteed to protect gauge devices in the explosion of a hydrogen-oxygen mixture. It is devoid of the main disadvantage of all liquid dampers with a capillary channel (including the prototype) - clogging of the capillary channel. In the proposed design, the fluid flow is inhibited by openings of a relatively large diameter - 2-3.5 mm, through which, when the electrolyzer is turned on and off, the fluid is run, washing them and thereby preventing them from clogging. By varying the diameters of the holes and the amount of air in compartment B, dampers can be manufactured with almost any degree of damping. In addition, the proposed damper protects the gauge device even when air has leaked from under it and the entire compartment under it is filled with liquid, since there is always air in compartment B that must be compressed so that the pressure under the gauge device increases. This is significant, because it turned out that during prolonged use of the damper, air from under the gauge device can flow out (along the thread) at a near-zero speed and it is not possible to guarantee the occurrence of such a leak over time.

Literature

[1] Mulev Yu.V. Manometers. M .: ed. MPEI, 2003 - paragraph 8.2.

Claims (2)

1. Damper for manometric devices, comprising a housing equipped with a socket for connecting a pressure gauge and a nipple for supplying a measured gas pressure, characterized in that the internal cavity of the housing is divided into three compartments by vertical partitions, a gauge device is installed on one of the extreme compartments, and on the other - a gas supply nipple is mounted, a hole with a diameter of 2.0-3.5 mm is made in each partition near the bottom of the housing, while the extreme compartments are filled with a working fluid to the level of the nipple ode to gas. 2. Damper for manometric devices according to claim 1, characterized in that the vertical walls of the housing and the vertical partitions are made in the form of three coaxial pipes of different diameters, the length of each of which is greater, the smaller its diameter.

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