RU2285908C1 - Device for measuring level and density of liquid (variants) - Google Patents

Abstract

FIELD: engineering of devices for measuring level and density of liquid, pertains to measuring equipment, possible use in systems for measuring level and density of oil products and other liquids, including highly explosive ones, during their dispensing, receipt and storage.

SUBSTANCE: device contains sound duct in form of a string of magnetostriction material with damper and reading coil, first permanent magnet, first, upper, float in form of toroid, mounted with possible movement with second permanent magnet positioned on it, second, lower float with third permanent magnet positioned on it, also made in form of toroid, has means for holding weights, is in immersed state and is suspended on upper float by means of balancing chains, impulse generator, generator-amplifier, level measuring block, density measuring block, output of which is connected to level measuring block, indication block. Device has continuous measurement with high sensitivity threshold, broad density measuring range, level measuring correction depending on liquid density, good temperature stability, possible measuring of density on the surface of liquid, possible shifting of range of measurements both towards lower side of sound duct and towards upper side.

EFFECT: increased efficiency.

2 cl, 5 dwg

Description

The invention relates to the field of measuring equipment and can be used in systems for measuring the level and density of petroleum products and other liquids, including explosive ones, during their dispensing, reception and storage.

There are many devices that allow you to measure the level or density separately. So, for example, a device for measuring fuel level (see US patent No. 5076100, G 01 F 23/00, 1991) contains a sound duct of magnetostrictive material with a damper at one end, a read coil installed in front of the damper, three permanent magnets, one of which it is fixed at the end of the sound pipe from the side of the read coil, and the other two are located on the floats, an amplifier-driver, a pulse generator and a counter. This device allows you to measure two levels of liquids with different densities.

There are also many varieties of continuous float densitometers that differ in the design and shape of the float, type (mechanical, electrical, pneumatic, optical) and the principle (inductive, potentiometric) of the float displacement transducers. For example, in US Pat. No. 3,808,893, a floating float with an inductive displacement encoder core is suspended directly from the spring. A number of other varieties of floats for the same purpose are discussed in US patent No. 3827306.

A fairly complete overview of devices for measuring density is presented in the book by S. S. Kivilis "Density meters" ed. Energia, Moscow, 1980, where various types of densitometers, including float meters, are examined in detail. Float densitometers are classified according to two functional characteristics - with partial immersion of the float and with full immersion of the float.

Readings of densitometers with partial immersion of the float, i.e. located on the surface, depend on the surface tension of the liquid, which, in turn, is determined by a number of factors (such as pressure, temperature, wettability) and, as a rule, is a variable. This leads to a decrease in measurement accuracy. To exclude the influence of surface tension allow densitometers with floaters full immersion (float-weight densitometers). Density meters of complete immersion include the so-called chain densitometers, the principle of operation of which is described in the book by S. S. Kivilis "Density meters". Using chains allows you to balance the float in a wide range of density.

The indicated advantages of chain densitometers are realized in the patent for utility model RU 46854 U1.

However, all of these solutions are not tied to the surface of the liquid and do not allow simultaneously with the density to control the level of liquid in the tank.

The closest in technical essence to the proposed device for measuring the level and density is a device for measuring the level and density described in the patent of the Russian Federation No. 2138028, G 01 F 23/68, G 01 N 9/10 1998

The specified device contains a first float installed with the possibility of movement, a transducer block, a sound duct installed in the protective casing in the form of a string of magnetostrictive material with a damper at its first end, a read coil installed under the damper, and a first permanent magnet located under the read coil, the second a float with a second permanent magnet mounted under the first permanent magnet, with the ability to move along the sound duct, and the first float contains a third permanent This magnet is located between the second float and the second end of the sound duct with the possibility of moving along the sound duct, the lower part of the first float is made in the form of a cylinder, and the upper one contains n rods located at the end of the cylinder with the same pitch along the circumference, where n≥2, the second float is installed with the possibility of free movement between the rods of the first float, the converter unit includes an amplifier-driver, the inputs of which are connected to the outputs of the read coil, a pulse generator, counter, register memory, a register with parallel input and sequential shift of information, two start pulse shapers, an address decoder, a ready signal shaper, a lock shaper, two keys, the input of the first of which is connected to the second end of the sound duct, and the input of the second is connected to the first end of the sound duct, and the bus exchange, the output of the amplifier-driver is connected to the clock input of the register with parallel input and sequential shift of information, the output of the first driver pulse triggers connected to the reset input a meter, the counting input of which is connected to the output of the counter pulse generator, the information output of the counter through the memory register is connected to the exchange bus, which is connected to the input of the address decoder, the first output of which is connected to the enable input of reading the memory register, the second and third outputs of the address decoder are connected respectively to the input of the first trigger pulse shaper and the second input of the ready signal shaper, the first input of which is connected to the memory register write enable input and register output with parallel input and sequential shift of information, the fourth output of the address decoder is connected to the input of the register selection code record with parallel input and serial shift of information, the parallel inputs for input of which information and the output of the ready signal generator are connected to a common bus, the control inputs of the first and second keys are connected respectively, with the outputs of the first and second drivers of the trigger pulse, and the outputs with a common bus, the inputs of the second driver of the trigger pulses and the driver and blocking pulses are connected respectively to the fifth and second outputs of the address decoder, and the output of the blocking pulse shaper is connected to the register blocking input with parallel input and serial shift of information, the sound duct at a point located between the first magnet fixed at a fixed distance from the read coil and the read coil connected to a power source.

To simplify, this device can be represented in the form depicted in figure 1. The device comprises a sound duct 1 in the form of a string of magnetostrictive material with a damper 3 at its first end, a first permanent magnet 6 located under the read coil 7 installed under the damper 3, a first float mounted for movement with a magnet 5 located on it, and a second float with a second permanent magnet 4 with the ability to move along the sound duct, the lower part of the second float is made in the form of a cylinder, and the upper contains located on the end of the cylinder with the same pitch along the circumference there are n rods, where n≥2, the first float is installed with the possibility of free movement between the rods of the second float, density measuring unit 9, level measuring unit 10, indicating unit 11, pulse shaper 2, the first input of which is connected to the density measuring unit 9, the second the input is connected to the level measuring unit 10, and the outputs are connected to the two ends of the sound duct 1, made in the form of a string of magnetostrictive material, the amplifier-former 8, the inputs of which are connected to the read coil 3, the first output is connected is connected to the density measuring unit, and the second output is connected to the level measuring unit 10, the outputs of the density measuring unit 9 and the level measuring unit 10 are connected to the first and second inputs of the indication unit 11.

The design of the device is shown in figure 3 of the description of the patent of the Russian Federation No. 2138028. The numbering of the main elements corresponds to the simplified diagram of the device shown in figure 1.

The device depicted in figure 1, operates as follows.

Level and density measurements are based on measurements of the propagation time of ultrasound in a magnetostrictive waveguide. The propagation velocity of ultrasound in the waveguide is practically independent of pressure and humidity. The influence of temperature is automatically compensated using a special algorithm for processing time intervals of ultrasound propagation.

At the command of a density measuring unit 9 or a level measuring unit 10, an ultrasonic wave is generated using a pulse shaper 8 using the magnetostriction principle directly in a waveguide 1 made of a special steel wire with magnetostrictive properties and located inside the case of non-magnetic material.

When the alternating magnetic field created by the current pulse in the waveguide 1 and the field of permanent magnets 4, 5 and 6 interact, a deformation of the crystal structure of the waveguide occurs, which creates a mechanical wave propagating at an ultrasonic speed. An ultrasonic wave arising at the locations of the magnets 4, 5 and 6 propagates along the waveguide 1 in both directions from the place of occurrence. Ultrasonic waves in the upper part of the waveguide, due to the inverse magnetostrictive effect, are converted by the read coil 7 into electrical pulses and then are damped by the damper 3. These pulses are fed to the driver amplifier 8, where they are converted into a rectangular shape and then transferred to the density measuring unit 9 and the level measuring unit 10 The time interval between the moment of generation of the ultrasonic wave and its conversion into electrical pulses is proportional to the measured distance, ie, the position of the floats. In this case, the moments of conversion of ultrasonic waves into electrical pulses are spaced in time, and analysis of the number of pulses and the corresponding time intervals will determine the position of each float, and thus measure the level and density of the liquid.

Mathematically, it looks like this: at the first stage, a digital code corresponding to the distance is recorded in the density measuring device and the level measuring device

K _x1 = FX1 / ν; K _x2 = FX2 / ν, K _(2A-B) = F · (2A-B) / ν,

where ν is the propagation velocity of the ultrasonic wave;

F is the frequency of the counter pulse generator 1;

X1, X2, (2A-B) are the distances to the read coil traveled by ultrasonic waves from magnets 5, 4, 6.

After receiving the codes K _x1 , K _x2 and K _(2A-B) , the values of X1 and X2 are calculated by the formulas:

X1 = (2A-B) K _x1 / K _(2A-B) and

X2 = (2A-B); K _x2 / K _(2A-B) ,

where (2A-B) is the scale factor.

The presence of the calibration value K _(2A-B) in the formula allows automatic compensation of the influence of destabilizing factors (temperature, aging, technological spread). The difference (X1-X2) should be constant with a constant fluid density. When the distance X1 corresponds to the liquid level, and the distance X2 (density float) varies in proportion to the density. Thus, by measuring with a hydrometer the density of the reference liquid ρ _et and using a device for measuring the level and density, the distance between the two floats:

h _et = X _1et -X _2et ,

where X _1et and X _2et are the distances to the floats in the reference fluid, it will be possible to determine the density of another fluid by the formula:

^ρ meas = m / (V-SΔh),

where m is the mass of the density float, determined by weighing;

V is the volume of the displaced reference fluid, is calculated by measuring ρ _et hydrometer, V = m / ρ _et ,

where S is the cross-sectional area of the upper (immersed) part of the density float, determined by measuring the float;

Δh, -h _floor , -h _ISM - change in the distance between two floats in liquids with a reference and measured density;

Δh = h _et , - h _meas.

The distance between the two floats is calculated by the formula:

h = X _{MOD 1izm} -X _2izm.

The product S · Δh can be positive or negative depending on the increase or decrease in the measured density compared to the reference.

The measurement results from the density measuring unit 9 and the level measuring unit 10 enter the display unit 11 and are displayed in a convenient form for operation. Instead of a display unit, a computer can be connected.

The above device has a fairly simple design, medium accuracy, has a constant amplitude of the bias current of the sound duct in the area of the read coil, which allows you to make the sensor length up to 4 meters and ensure its reliability.

However, this device has several disadvantages inherent to partial immersion surface densitometers, namely, as noted above, depend on the surface tension of the liquid, which, in turn, is determined by a number of factors (such as pressure, temperature, wettability) and, as a rule, is a variable. All these factors lead to an increase in density measurement error. In addition, it should be noted that this device is not suitable for measuring density with high accuracy in tanks with high pressure, for example, in tanks with liquefied gas, and the magnitude of the error is proportional to the increase in pressure. In addition, these devices give a big error when measuring the density of a liquid with a high viscosity or with a viscosity that varies greatly with temperature. It should also be noted that the immersibility of the level float depends on the density of the liquid, which gives an error in measuring the level, while in this device no correction is provided to compensate for this error. It should also be noted that the location of the first permanent magnet at the first, upper, end of the sound duct allows shifting the working range of measurements to the lower side, and in some cases there is a technical need to shift the working range of measurements to the upper side, for example, with limited dimensions of the tank pit.

The problem to which the invention is directed, is to create a device for accurate measurement of level and density on the surface of a liquid with the ability to work in a wide range of density.

The proposal consists of two inventions related to two objects of the same purpose, solving the same problem and providing the same technical result (two options).

In the first embodiment, the subject of the invention is a device containing a sound guide in the form of a string of magnetostrictive material with a damper and a read coil at its first end, a first permanent magnet located under the read coil installed under the damper, and a first toroid-shaped float mounted for displacement it has a second permanent magnet, a second float with a third permanent magnet, with the ability to move along the sound duct, a pulse shaper, the first input to of which is connected to the first output of the density measuring unit, the second input is connected to the first output of the level measuring unit, and the outputs are connected to the two ends of the sound duct, the driver amplifier whose inputs are connected to the read coil, the first output is connected to the input of the density measuring unit, the second output is connected with the first input of the level measuring unit, the second output of which is connected to the input of the display unit, the second input of which is connected to the second output of the density measuring unit, the third additional the first output of the density measuring unit, connected to the second additional input of the level measuring unit, and the second, lower, float with a permanent magnet located on it, made in the form of a toroid, has devices for attaching weights, is in the submerged position and suspended from the upper float with balancing chains.

In the second embodiment, the subject of the invention is a device containing a sound guide in the form of a string of magnetostrictive material with a damper and a read coil at its first end, mounted under the damper, at its first end, the first toroid-shaped float mounted for movement with the second one located on it a permanent magnet, a second float with a third permanent magnet, with the ability to move along the sound duct, a pulse shaper, the first input of which is connected to the first output of the measuring unit rhenium density, the second input is connected to the first output of the level measurement unit, and the outputs are connected to the two ends of the sound duct, the amplifier-driver, the inputs of which are connected to the read coil, the first output is connected to the input of the density measurement unit, the second output is connected to the first input of the level measurement unit the second output of which is connected to the input of the display unit, the second input of which is connected to the second output of the density measurement unit, the third additional output of the density measurement unit is introduced in the device, is connected the second, lower, float with a permanent magnet located on it, made in the form of a toroid, has fixtures for attaching weights, is in the submerged position and suspended from the upper float by means of balancing chains, and the first permanent magnet located on the second, lower, end of the sound pipe.

The technical result is the creation of a new device for measuring the level and density of a liquid, having continuous measurement with a high threshold of sensitivity, a wide range of density measurement, correction of level measurement depending on the density of the liquid, good temperature stability, the ability to measure density on the surface of the liquid, the ability to shift the measuring range both in the lower side of the sound duct, and in the upper.

The indicated properties are obtained due to the use of an additional connection between the density measuring unit and the level measuring unit, the introduction of which makes it possible to take into account the change in immersion of the level float depending on the change in the density of the liquid, the system of double floats for measuring density, in which the upper level float is on the liquid surface and the lower the density float is completely immersed in the liquid and suspended from the level float using balancing chains and the possibility of installing the first oyannogo magnet like the first, upper end of the acoustic duct, which allows to shift the measurement range downward, and the second, lower end thereof, that allows to shift the measuring range upwards.

Figure 2 schematically shows a device for measuring the level and density with the location of the first permanent magnet in the upper part of the sound duct, figure 3 schematically shows a device for measuring the level and density with the location of the first permanent magnet in the lower part of the sound duct, figure 4 schematically shows device design with the location of the first permanent magnet in the upper part of the sound duct, figure 5 schematically shows the design of the device with the location of the first permanent magnet in the bottom th part of the sound duct.

The numbers in the figures indicate:

1 - sound duct (magnetostrictive waveguide);

2 - pulse shaper;

3 - damper;

4 - the third permanent magnet (located on the density float);

5 - the second permanent magnet (located on the level float);

6 - the first permanent magnet;

7 - read coil;

8 - amplifier-driver;

9 - block density measurement;

10 - block level measurement;

11 - display unit;

12 - the first float (level float);

13 - the second float (density float);

14 - case of non-magnetic material;

15 - balancing chains;

16 - device for mounting weights.

In the first embodiment (Figs. 2 and 4), the device comprises a sound duct 1 in the form of a string of magnetostrictive material with a damper 3 and a read coil 7 at its first end, the first permanent magnet 6 located under the read coil 7, mounted under the damper 3, the first float 12 in the form of a toroid, mounted for movement with a second permanent magnet 5 located on it, a second float 13 with a third permanent magnet 4, mounted for movement along the sound duct 1, density measuring unit 9, measuring unit level 10, indicating unit 11, pulse shaper 2, the first input of which is connected to the first output of the density measuring unit 9, the second input is connected to the first output of the level measuring unit 10, and the outputs are connected to the two ends of the sound duct 1, amplifier-shaper 8, inputs which are connected to the read coil 7, the first output is connected to the input of the density measuring unit 9, the second output is connected to the first input of the level measuring unit 10, the second output of which is connected to the input of the indicating unit 11, the second input of which is connected to the second output of the density measuring unit 9, the third additional output of the density measuring unit 9 is connected to the second additional input of the level measuring unit 10, and the second, lower, float 13 with a third permanent magnet 4 located on it, made in the form of a toroid, has devices for fixing weights 16, is in a submerged position and suspended from the upper float 12 using balancing chains 15.

In the second embodiment (FIGS. 3 and 5), the device comprises a sound duct 1 in the form of a string of magnetostrictive material with a damper 3 and a read coil 7 at its first end, mounted under the damper 3, at its first end, the first float 12 in the form of a toroid, installed with the possibility of moving with the second permanent magnet 5 located on it, the second float 13 with the third permanent magnet 4, with the ability to move along the sound duct 1, the density measuring unit 9, the level measuring unit 10, the indicating unit 11, pulse shaper 2, per the output of which is connected to the first output of the density measuring unit 10, the second input is connected to the first output of the level measuring unit 9, and the outputs are connected to the two ends of the sound duct 1, the amplifier-shaper 8, the inputs of which are connected to the read coil 7, the first output is connected to the input density measuring unit 9, the second output is connected to the first input of the level measuring unit 10, the second output of which is connected to the input of the indicating unit 11, the second input of which is connected to the second output of the density measuring unit 9, the third additional the output of the density measuring unit 9 is connected to the second additional input of the level measuring unit 19, and the second, lower, float 13 with a third permanent magnet 4 located on it, made in the form of a toroid, has devices for attaching weights 16, is in a submerged position and suspended to the upper float 12 using balancing chains 15, and the first permanent magnet 6 is located on the second, lower, end of the sound pipe 1.

The device operates as follows.

Level and density measurements are based on measurements of the propagation time of ultrasound in a magnetostrictive waveguide. The propagation velocity of ultrasound in the waveguide is practically independent of pressure and humidity. The influence of temperature is automatically compensated using a special algorithm for processing time intervals of ultrasound propagation.

At the command of a density measuring unit 9 or a level measuring unit 10, a pulse generator 8 generates an ultrasonic wave according to the magnetostriction principle directly in the waveguide 1, made of a special steel wire with magnetostrictive properties and located inside the body of non-magnetic material 14.

When the alternating magnetic field created by the current pulse in the waveguide 1 and the field of permanent magnets 4, 5 and 6 interact, a deformation of the crystal structure of the waveguide occurs, which creates a mechanical wave propagating at an ultrasonic speed. An ultrasonic wave arising at the locations of the magnets 4, 5 and 6 propagates along the waveguide 1 in both directions from the place of occurrence. Ultrasonic waves in the upper part of the waveguide, due to the inverse magnetostrictive effect, are converted by the read coil 7 into electrical pulses and then are damped by the damper 3. These pulses are fed to the driver amplifier 8, where they are converted into a rectangular shape and then transferred to the density measuring unit 9 and the level measuring unit 10 The time interval between the moment of generation of the ultrasonic wave and its conversion into electrical pulses is proportional to the measured distance, ie position of the floats. At the same time, the moments of conversion of ultrasonic waves into electric pulses are spaced in time, and analysis of the number of pulses and the corresponding time intervals will determine the position of each float and thus measure the level and density of the liquid.

Mathematically, it looks like this: at the first stage, a digital code is recorded in the density measuring device and the level measuring device, corresponding to the distance from the read coil to magnets 4 and 5 of floats 12 and 13-X1 and X2, as well as reference distances A and B. After receiving codes, the values of the indicated distances are calculated by the formulas:

A = Vt _A (1 + γ) + t _ZD

B = Vt _B (1 + γ) + t _ZD

X1 = Vt ₁ (1 + γ) + t _ZD

X2 = Vt ₂ (1 + γ) + t _ZD ,

where V is the speed of ultrasound in the wire;

t _A , t _B , t ₁ , t ₂ - the time during which the ultrasonic wave travels the distance And; AT; X1; X2;

γ - methodological error due to aging and temperature deviations of the wire parameters;

t _ZD - delay time due to imperfections in the start and reception of an ultrasonic wave in a magnetostrictive waveguide.

Depending on the required accuracy of level and density measurements, the current distance between the magnets ΔH _tech = X1-X2 can be calculated in three ways with different additional errors depending on spurious influences.

1. Absolutely invariant (most accurate) is when, after processing the data, ΔН _{tech is} insensitive to γ and t _ЗД :

ΔH _tech = [(AB) (t ₁ -t ₂ )] / (t _A -t _B ).

2. Integral quasi-invariant (medium accuracy) is when ΔН _{tech is} insensitive to γ and partially sensitive to t _ZD due to one integral reference distance A.

ΔH _tech = [A (t ₁ -t ₂ )] / (t _A -Δ _ZD ),

where Δ _ED = t _ZD / V.

3. Local quasi-invariant (with low accuracy) - this is when ΔН _{tech is} insensitive to γ and partially sensitive to t _ZD due to one local reference distance B;

ΔH _tech = [B (t ₁ -t ₂ )] / (t _B -Δ _ZD ).

Choosing one of three options allows you to find the best option for the necessary accuracy and cost of the device.

The measurement of the density of the liquid by the new device is based on the fact that calibrated metal chains with a constant mass of a unit length are suspended from the float 13 with a known mass and volume at one end, and the second end of the chain is suspended from the float 12 (whose density is less than the density of the liquid and whose mass is much greater than the mass suspended chains).

In order for the device to cover a sufficiently wide range of densities with a relatively short length of chains, devices for fastening weights are provided on the float, the same effect is achieved by using chains of different weights. Devices for fastening weights can be made in the form of loops, hooks, latches or other similar solutions.

The density value is measured in the density measuring unit using the following mathematical model (for a detailed conclusion, see: S. S. Kivilis "Density meters" ed. Energia 1980, pp. 63, 64):

where M _P , V _P - mass and volume of the float 13;

- половина суммарной массы единицы длины всех подвешенных цепей;

- half the total mass per unit length of all suspended chains;

ΔH _ET. - reference (obtained by graduation) the distance between the magnets;

M _GR - mass of suspended additional weights;

ρ _CHAIN. ; ρ _GR. - the density of the material of the chains and the material of weights.

To give stability to the float 13 and ensure its centering, several chains are used (usually from two to four), their free ends being fixed on the movable float 12 (when the level changes, the float 12 moves and moves proportionally magnets of both its own and the float 13). From each chain on the float 13 acts a force directed tangentially to the chain line and depending on the length of the chain. The vertical component of this force, compensating for the change in the buoyancy force with a change in the density of the liquid, depends on the movement of the float 13 in accordance with the mathematical model. The balanced state of the float 13 (at a constant density) is stored at any location of the float 12 (over the level range). The immersion of the float 12 changes when the position of the float 13 changes (when the density changes) and is taken into account when processing the position signals of the float magnets.

From the foregoing, we can conclude that the density measurement is independent:

1 - from the movement of the float 12;

2 - from gas pressure;

3 - from the wettability of the float 12.

The measurement of the level (phase separation) Н _У = Н _К + h by the device is based on measuring the displacement of the float 12 (Н _К ) and taking into account its depth of immersion in the liquid (h). Signal processing is carried out by the level measurement unit.

The measurement of the displacement of the float 12 is carried out by the magnetostrictive method (using a special calibration unit during graduation for displacement of the floats).

If you choose the mass of the float 12 (M _P ) is significantly greater than the change in mass of the chain (M _C ) and the mass of the meniscus (M _M ):

M _P ≫ M _C and M _P ≫ _{M M} ,

then the depth of immersion of the float h under normal conditions will be determined by the formula

h = (M _P / ρS) + (M _CCO / ρS),

where Mtso is the initial mass of the chain suspension;

S - working section of the float 12.

The implementation of accurate level measurement, taking into account the change in the depth of immersion of the level float depending on the density of the liquid, is carried out due to the newly introduced additional connection between the density measuring unit and the level measuring unit.

The measurement results from the density measuring unit 9 and the level measuring unit 10 enter the display unit 11 and are displayed in a convenient form for operation. Instead of the display unit or in conjunction with it, a computer can be connected.

The density measuring unit and the level measuring unit are implemented on microprocessors, which easily allows you to carry out the necessary signal conversions and perform the necessary mathematical calculations according to a given program.

The proposed device has better temperature stability than the prototype, because it does not have working cross sections with temperature dependence and menisci.

In the proposed device, it is easy to expand the range of density measurements (by extending the chain of the chain suspension or attaching additional weights), and in the float - for this it is necessary to change the design of the float, which entails a large investment of time and money.

In the manufacture of a prototype from metal, the upper part of the density float is in the air and is subject to the formation of condensate on the surface and severe contamination, which leads to a decrease in the density measurement accuracy, and the possibility of manufacturing metal floats expands the scope of the device: for example, in the food and chemical industries. In the proposed device, the density float is always immersed and accordingly devoid of the above disadvantage, and can be made of metal.

It should also be noted that due to the use of low operating voltages and low currents, the described device for measuring the level and density is easily implemented in explosion-proof design, which allows it to be used when measuring in explosive atmospheres, for example, when working with oil products or liquefied gases.

A mock-up was made at the applicant enterprise, and then a prototype of the described device was made and tests were carried out that fully confirmed the correctness of the proposed solution.

Claims (2)

1. Device for measuring the level and density of a liquid, containing a sound guide in the form of a string of magnetostrictive material with a damper and a read coil at its first end, a first permanent magnet located under the read coil installed under the damper, the first toroidal float installed with the possibility movement with a second permanent magnet located on it, a second float with a third permanent magnet, with the ability to move along the sound duct, density measurement unit, uro measurement unit nya, display unit, pulse shaper, the first input of which is connected to the first output of the density measuring unit, the second input is connected to the first output of the level measuring unit, and the outputs are connected to the two ends of the sound duct, the amplifier-shaper, whose inputs are connected to the read coil, the first output connected to the input of the density measurement unit, the second output is connected to the first input of the level measurement unit, the second output of which is connected to the input of the display unit, the second input of which is connected to the second output of the measurement unit density, characterized in that the third additional output of the density measuring unit is connected to the second additional input of the level measuring unit, and the second, lower, float with a third permanent magnet located on it, made in the form of a toroid, has devices for attaching weights, is immersed position and suspended from the upper float using balancing chains. 2. A device for measuring the level and density of a liquid, containing a sound guide in the form of a string of magnetostrictive material with a damper and a read coil installed under the damper at its first end, the first float in the form of a toroid mounted for movement with a second permanent magnet located on it , a second float with a third permanent magnet, with the ability to move along the sound duct, a density measuring unit, a level measuring unit, an indication unit, a pulse shaper, the first input of which connected to the first output of the density measuring unit, the second input is connected to the first output of the level measuring unit, and the outputs are connected to the two ends of the sound duct, the driver amplifier, the inputs of which are connected to the read coil, the first output is connected to the input of the density measuring unit, the second output is connected to the first input of the level measuring unit, the second output of which is connected to the input of the display unit, the second input of which is connected to the second output of the density measuring unit, characterized in that the third additional output the density measuring unit is connected to the second additional input of the level measuring unit, the second, lower one, the float with the third permanent magnet located on it, made in the form of a toroid, has devices for attaching weights, is in the submerged position and suspended from the upper float using balancing chains, and the first permanent magnet is located on the second, lower, end of the sound duct.

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