CN202002680U - Temperature-pressure compensation metal tube float flowmeter - Google Patents

Abstract

The utility model provides an integrated temperature-pressure compensation metal tube float flowmeter, which is used for real-time measurement of gas (steam) pressure, temperature and flow and has the function of temperature and pressure compensation. The integrated temperature-pressure compensation metal tube float flowmeter comprises a flow sensor and an indicator, the flow sensor comprises a measuring tube, a temperature sensor and a pressure sensor, the interior of the measuring tube consists of a conical tube (a porous board) and a float, the float is positioned in the conical tube (the porous board), a cylindrical steel magnet is inset into the float, the temperature sensor mounted on the measuring tube is used for measuring the temperature of gas in the measuring tube, the pressure sensor mounted on the measuring tube is used for measuring the pressure of the gas in the measuring tube, a flow card is mounted in the indicator, a magnetic sensor and a flow calculation module are arranged on the flow card, the magnetic sensor is connected with the flow calculation module, the temperature sensor and the pressure sensor are respectively connected with the flow card, and pressure and temperature data of the gas in the measuring tube are transmitted to the flow card in real time.

Description

The temperature and pressure compensation metal pipe float flow meter

Technical field

The utility model relates to a kind of flow measurement device that is applicable to industrial process control, relates in particular to a kind of temperature and pressure that can carry out in real time and compensates the integrated temperature and pressure compensation metal pipe float flow meter that is used for gas (steam) flow measurement.

Background technology

The measuring method and the calibration steps of metal pipe float flow meter are as follows:

The measurement of existing metal pipe float flow meter needs user's each parameter under service condition is converted, and realizes measuring by the calibration under the standard conditions.

Suppose that the user orders goods, and provides parameter under the gas condition of work: pressure (MPa): P0; Temperature (℃): T0; Density (mark condition, kg/Nm ³): ρ; Flow range (m ³/ h, kg/h, Nm ³/ h or the like): 0～F.

Temperature and pressure under the type of user's measurement gas, the gas condition of work is varied, and the condition that instrument manufacturing plant can not simulated field is come calibrated meter.No matter what gas the user measures, instrument manufacturing plant generally uses the calibration of standard air flow apparatus to metal pipe float flow meter, needs like this flow range that the user gives is converted on the flow range of corresponding air, and reduction formula is as follows:

The normal flow of tested gas is Q _N(Nm/h);

$Q_S=\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{st}}}{{\mathrm{\ρ}}_s}\×\frac{P_s}{P_t}\×\frac{T_t}{T_s}}\×Q_N;$

The operation flow of tested gas is Q _t(m ³/ h);

$Q_S=\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{st}}}{{\mathrm{\ρ}}_s}\×\frac{P_t}{P_s}\×\frac{T_s}{T_t}}\×Q_t;$

The mass rate of tested gas is Q _m(kg/h);

$Q_S=\sqrt{\frac{1}{{\mathrm{\ρ}}_t\×{\mathrm{\ρ}}_s}}\×Q_m;$

In the formula:

Q _N: the maximum volume flow (Nm of gas under the calibration state ³/ h);

Q _t: the maximum volume flow (m of gas under mode of operation ³/ h);

Q _m: the biggest quality flow (kg/h) of gas under mode of operation;

Q _s: reference fluid air mass flow (m ³/ h);

ρ _sDensity (the kg/m of air under the calibration state ³);

ρ _StDensity (the kg/m of gas under the calibration state ³);

ρ _t: the density (kg/m of gas under mode of operation ³);

P _s: the absolute pressure (0.1013MPa) of air under the calibration state;

P _t: the absolute pressure (MPa) of gas under mode of operation;

T _s: the absolute temperature (293.15) of air under the calibration state;

T _t: the absolute temperature (K) of gas under mode of operation.

Flow range to the customer requirements measurement gas: 0～F carries out scale and converts, air mass flow: 0～F0 under the corresponding mark condition.On the air mass flow standard set-up, metal pipe float flow meter is calibrated, calibrate n point (if calibrating 10 points) generally speaking.Calibration data is write flow integrated circuit board (circuit board) be used for flowmeter calculating.

Flow integrated circuit board storage calibration data form:

The float height

h0

h1

h2

h3

h4

h5

h6

h7

h8

h9

h10

Flow value

0

0.1F

0.2F

0.3F

0.4F

0.5F

0.6F

0.7F

0.8F

0.9F

F

Described flow transmitter will carry out linear interpolation and obtain flow value according to calibration data stored wherein from the float height of described sensor, and will convert this flow value to the industrial standard current signal and be sent to the pulpit by cable.

From the measuring method of above-described metal pipe float flow meter as can be seen, the calibration data of the metal pipe float flow meter of measurement gas is (a pressure: P0 under certain working condition of providing of user, temperature: calibration data T0), at this working condition (pressure: P0, temperature: T0) measured value of metal pipe float flow meter is accurately down, but when gaseous tension and temperature and user in the on-the-spot pipeline provide when not being inconsistent, measurement will be inaccurate.Occur that this Things are quite normal, reason is as follows:

1) if new project, the gas parameter that the user provides (temperature, pressure) is a design parameter, and gas parameter and design parameter have difference in the pipeline when putting into operation actual motion etc. project;

When 2) normally moving immediately, gaseous tension and temperature variation also are very normal in the pipeline that factors such as seasonal variations, equipment cause.

Summary of the invention

Fundamental purpose of the present utility model, be to provide a kind of metal pipe float flow meter that has temperature and pressure compensation, gaseous tension and temperature variation in the difference that solution changes because of gas parameter in design parameter and the actual pipeline, the pipeline that causes because of factors such as seasonal variations and equipment when normally moving make the problem that error occurs of measuring.

In order to achieve the above object, the utility model provides a kind of integrated temperature and pressure compensation metal pipe float flow meter, comprises flow sensor, indicator, wherein,

Described flow sensor mainly is made of measuring tube, temperature sensor and pressure transducer, and measuring tube inside is made of tapered tube (or orifice plate) and float, and described float is arranged in described tapered tube (orifice plate), and described float inside is embedded with the cylindricality magnet steel;

The flow integrated circuit board is housed in the described indicator, and described flow integrated circuit board is provided with Magnetic Sensor and flow rate calculation module, and this Magnetic Sensor is connected with this flow rate calculation module;

It is characterized in that described temperature and pressure compensation metal pipe float flow meter also comprises temperature sensor and pressure transducer, wherein,

Described temperature sensor is installed on the described measuring tube, is used to measure the gas temperature in the described measuring tube;

Described pressure transducer is installed on the described measuring tube, is used to measure the gaseous tension in the described measuring tube;

Described temperature sensor, described pressure transducer respectively with described flow current plate card connection.

During enforcement, described temperature sensor, described pressure transducer are installed on respectively on the sidewall of described measuring tube, and described temperature sensor and described pressure transducer are positioned at upstream or other position of described float.

Compared with prior art, temperature and pressure compensation metal pipe float flow meter described in the utility model, at measuring tube sidewall setting pressure sensor and temperature sensor, measure the temperature and pressure of the gas (steam) in the described measuring tube in real time, and temperature value and the force value current according to gas (steam), in conjunction with the scale reduction formula, real-time update flow transmitter internal calibration data are the calibration data under current pressure and the temperature, use the calibration data after upgrading to carry out flow rate calculation, thereby reach the temperature pressure compensation effect, guaranteed the precision of gas flow measurement.

Description of drawings

Fig. 1 is the structural representation of existing metal pipe float flow meter;

Fig. 2 is the structural representation of a specific embodiment of temperature and pressure compensation metal pipe float flow meter described in the utility model.

Embodiment

Existing metal pipe float flow meter comprises sensor (being measuring tube) and indicator, wherein,

As shown in Figure 1, described measuring tube 1 inside is made of tapered tube (or orifice plate) 3 and float 2;

Described float 2 is arranged in described tapered tube 3, and float 2 inside are embedded with the cylindricality magnet steel, forms magnetic field around float;

Described indicator 4 is equipped with flow integrated circuit board 5, and Magnetic Sensor 6 is arranged on the flow integrated circuit board, and the current plate cartoon is crossed magnetic-coupled mode and detected float position in the measuring tube.

When detected fluid is passed through the annular space that forms between described tapered tube 3 and the described float 2 from bottom to top, be subjected to the effect of three power: G (gravity), F (buoyancy) and P (differential pressure) and viscous force (gas is ignored), when G=F+P, float is stabilized in certain altitude, and the height value of float is corresponding with the instantaneous delivery value.

Described measuring tube converts the variation of fluid flow value the variation of float height to, and the variation range of float height is approximately: 0-50mm.

Described intelligent flow integrated circuit board uses the float position that records to be converted to flow value demonstration or industrial standard current signal (4-20mA) teletransmission that the user can obtain in conjunction with calibration data.

Metal pipe float flow meter can be measured the flow value of liquid, gas and steam, and the measurement of gas (steam) is to carry out under the certain condition of temperature and pressure, temperature and pressure compensation metal pipe float flow meter described in the utility model is the technological improvement of making at gas flow measurement and flow measurement of steam, therefore, only gas flow measurement is described (flow measurement of steam is identical with gas flow measurement) below.

In order to solve the defective of metal pipe float flow meter in gas flow measurement, the utility model is at measuring tube sidewall setting pressure sensor and temperature sensor, measure the temperature and pressure of the gas in the described measuring tube in real time, and temperature value and the force value current according to gas, in conjunction with the scale reduction formula, real-time update flow transmitter internal calibration data are the calibration data under current pressure and the temperature, use the calibration data after upgrading to carry out flow rate calculation, thereby reach the temperature pressure compensation effect, guaranteed the precision of gas flow measurement.

Except comprising above-mentioned measuring tube, indicator, temperature and pressure compensation metal pipe float flow meter described in the utility model is equipped with temperature sensor and pressure transducer,

Described temperature sensor, described pressure transducer are installed on the sidewall of described measuring tube, are respectively applied for gas temperature, the gaseous tension measured in the described measuring tube;

On the flow integrated circuit board of metal pipe float flow meter, connect temperature sensor and pressure transducer, the online gas of pipeline (steam) pressure and temperature is passed to the flow integrated circuit board in real time by lead by lead;

Calibration data under the signal combination flow standard condition of the inner integrated circuit board collection of indicator pressure, temperature sensor adopts flow-compensated algorithm, calculates the actual flow value in preceding pipeline, realizes temperature and pressure compensation.Guaranteed the precision of gas flow measurement.

Below by a specific embodiment the utility model is described:

As shown in Figure 2, the structured flowchart of the described temperature and pressure compensation metal pipe float flow meter of the utility model one specific embodiment,

Described flow sensor mainly is made of measuring tube 21, temperature sensor 24 and pressure transducer 25,

Described measuring tube inside is made of tapered tube 23 (or orifice plate) and float 22, and float 22 is arranged in tapered tube 23 (orifice plate), and float 22 inside are embedded with the cylindricality magnet steel;

Described temperature sensor 24, pressure transducer 25 are installed on respectively on the sidewall of described measuring tube 21, be used for detecting the temperature and pressure of measuring tube 21 gases (steam), and described temperature sensor 24 and described pressure transducer 25 are installed on upstream or other position of described float 22; Described Magnetic Sensor 28 is positioned on the flow integrated circuit board 27; By measuring magnetic field detection float 22 positions.

Described flow integrated circuit board 27 is installed on the inside of indicator 26;

The effect of described flow integrated circuit board 27 is that float position detects, pressure, temperature signal collection, and flow rate calculation, flow shows and (4-20) mA electric current output (two-wire system).

More than explanation is just illustrative for utility model; and nonrestrictive, those of ordinary skills understand, under the situation of the spirit and scope that do not break away from claims and limited; can make many modifications, variation or equivalence, but all will fall in the protection domain of the present utility model.

Claims (2)

1. an integrated temperature and pressure compensation metal pipe float flow meter comprises flow sensor, indicator, wherein,

Described flow sensor mainly is made of measuring tube, temperature sensor and pressure transducer, and measuring tube inside is made of tapered tube and float, and described float is arranged in described tapered tube, and described float inside is embedded with the cylindricality magnet steel;

The flow integrated circuit board is housed in the described indicator, and described flow integrated circuit board is provided with Magnetic Sensor and flow rate calculation module, and this Magnetic Sensor is connected with this flow rate calculation module;

It is characterized in that described temperature and pressure compensation metal pipe float flow meter also comprises temperature sensor and pressure transducer, wherein,

Described temperature sensor is installed on the described measuring tube, is used to measure the gas temperature in the described measuring tube;

Described pressure transducer is installed on the described measuring tube, is used to measure the gaseous tension in the described measuring tube;

Described temperature sensor, described pressure transducer respectively with described flow current plate card connection.

2. temperature and pressure compensation metal pipe float flow meter according to claim 1 is characterized in that,

Described temperature sensor, described pressure transducer are installed on respectively on the described measuring tube, and described temperature sensor and described pressure transducer are positioned at the upstream of described float.

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