SU1239552A1 - Viscometer - Google Patents

Abstract

The invention relates to the measurement of the viscosity of liquid and gaseous media. The purpose of the invention is to improve the measurement accuracy. Another proposed is a viscometer with a replaceable capillary, which includes a limit switch, a system for recording the flow of the test substance through the captcall, a control unit, a pressure sensor, a shear repeater and a pneumatic sensor, and the pressure sensor is connected to the pressure chamber through the repeater. the substance to be examined, and the temperature sensor, with one of the repeater inputs with a shift. 1 il.

Description

The invention relates to the measurement of the viscosity of liquid and gaseous media and can be used in the petro-fm4ecKoft industry.

The drawing shows schematically the proposed viscometer.

. The viscometer contains a sensing element in the form of a capillary 1 fixed on the chamber 2 mounted on the flow chamber 3. The chamber 2 is equipped with an additional capillary A mounted in the upper part of the chamber 2 and connecting it to the buffer tank 5. A flow sensor 3 is mounted on the flow chamber 3 6 pressure connected to a shift repeater 7, the output of which through a relay 8 is connected to a buffer tank 5 The shift repeater 7 inputs that control the amount of shift are connected to the setpoint 9 and to the thermometer code consisting of 10 laminar and Urbulent 11 chokes. The inner cavity of the chamber 2 is connected to the final off

to

Capillary resistance 4 of the pressure in chamber 2 increases abruptly, which is reflected by an increase in pressure at the outlet e, repeat 5 liters 12, the comparison element 13 triggers, which triggers the relay 14, and at the time of the measuring system 15 a signal comes to the end of the measurement of the time of fluid flow through the capill 1. By the same command, the control unit 16 switches the relay 8 and the supply pressure exceeding the pressure in the flow chamber 3 and the liquid enter the chamber 5.

 5 is expelled from chamber 2. The scozimeter is ready for a new measurement cycle. After the 16-time control unit specified in the program expires, relay 8 is transferred and connects the repeater output with a shift of 7 to re 5. At the same time, the measuring system receives a signal at the beginning of the measurement. Compensation for temperature changes in viscosity

20

the reader, made in the form of repeated liquid 25 is carried out following a 12 shift, element 13

comparison and relay 14 connected to

time measuring system 15 and

control unit 16 connected

to relay 8. Throttle 17 serves for

food nutrition 12.

thirty

in a manner.

I

If at the time of viscosity measurement

the temperature of the test liquid is at the temperature to which the measurements are to be carried out (let, for example, the irregular viscosity be reduced to a temperature of + 50 ° C), a pressure drop will be created on the capillary. The viscometer works as follows .

When triggered by the control unit 16, the relay 8 connects to the buffer tank 5 the repeater 7 pressure equal to. .

RSG-RG

(one

where P is the outlet pressure of the pneumothermometer; P - output pressure sensor

pressure} Pjo., - pressure, dial.

Thus, on the capillary 1, a pressure differential is formed equal to

sp-p

(2)

and the liquid under the action of this pressure differential begins to flow into chamber 2, after filling which the liquid through the additional capillary 4 begins to flow into the buffer capacity 5. At the same time, due to the additional

The pressure in the chamber 2 rises abruptly, which is reflected by an increase in pressure at the output of the repeater 12, the comparison element 13 triggers, which triggers the relay 14, and at the time of the measuring system 15 a signal comes to the end of the measurement of the time of fluid inflow through the capillary 1 By the same command, the control unit 16 switches the relay 8 and the supply pressure exceeding the pressure in the flow chamber 3 and the liquid enter the chamber 5.

out of chamber 2 is pushed out. The scozimeter is ready for a new measurement cycle. After the 16-time control unit specified in the program expires, relay 8 is transferred and connects the repeater output with a shift of 7 to re 5. At the same time, the measuring system receives a signal at the beginning of the measurement. Compensation for temperature changes in viscosity

them way.

If at the time of viscosity measurement

the temperature of the liquid under study is equal to the temperature to which the measurements must be made (let, for example, irradiated viscosity be reduced to a temperature of & d +50 C.), then a differential pressure will be created on the capillary.

-P (6), where P (9o) is the value of the output signal of the thermometer at a temperature of. Assume that the temperature of the test liquid has decreased by dd. At the same time (due to the appearance of the temperature component)

the viscosity of the liquid under study increases by d (d)). In the absence of temperature compensation (i.e., at & const), this will lead to a temperature measurement error

Av (A ©) / V (9,),%.

In the proposed viscometer, the pneumatic thermal compensation scheme compensates for the resulting viscosity temperature component: in accordance with a decrease in the temperature of the test liquid, the output pressure of the thermometer P also decreases (by the value of dР (л0)) and, consequently, increases accordingly, the difference on the capillary re, 1

(i.e. the value (dO) will be subtracted from the pressure value Pja; f

 - ((l0)).

Such an increase in the differential leads to the fact that, despite the increase in viscosity due to a decrease in the temperature of the liquid, the flow rate through the capillary increases so that the discharge time of the installed portion of the liquid in chamber 2 remains the same. a change in the temperature of the test liquid will not affect the output signal of the viscometer. The degree of influence of the output signal of the pneumothermometer on the magnitude of the differential for a particular test fluid is determined by the viscosity-temperature characteristic of this fluid.

Form la invention

A viscometer containing a test substance chamber with a replaceable capillary, a limit switch, a system for recording the flow time of the test substance through a capillary, a control unit, characterized in that it is equipped with a pressure sensor of the test medium and a shear repeater in order to measure the measurement accuracy. and a pneumatic sensor of the temperature of the test medium, wherein the pressure sensor of the test medium is connected via a repeater with a shift to the chamber for the test substance, and the pneumatic temperature sensor is investigated This medium is connected to one of the entrances of the repeater with sdigom.

Editor V. Ivanova

Compiled by V. Voshchankin Tehred I. Popovich

Order 3387/41 Circulation 778 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing enterprise, Uzhgorod, st. Project, 4

Corrector T. Kolb

Claims (1)

A viscometer containing a chamber for the test substance with a replaceable capillary, a limit switch, a system for recording the time the test substance flows through the capillary, a control unit, characterized in that, in order to increase the accuracy of measurements, it is equipped with a pressure sensor of the test medium, a repeater with a shift and a pneumatic sensor temperature of the test medium, the pressure sensor of the test medium through a repeater with a shift connected to the chamber for the test substance, and a pneumatic temperature sensor of the test medium s connected to one of the repeater inputs with a shift.