CN201522317U - Online calibrating device of orifice-plate steam flow measuring system - Google Patents

Abstract

The utility model discloses an online calibrating device of an orifice-plate steam flow measuring system, which comprises a differential pressure calibrating module and a pressure calibrating module. The online calibrating device is characterized in that the differential pressure calibrating module is formed by a high-pressure flexible tube (1), a low-pressure flexible tube (2), a differential pressure transformer (3) for calibration, and a process calibrator A (4), wherein one end of the high-pressure flexible tube (1) is connected with a high-pressure input port of the differential pressure transformer (3)for calibration, one end of the lower-pressure flexible tube is connected with a low-pressure input port of the differential pressure transformer (3) for calibration, and an output port of the differential pressure transformer (3) for calibration is connected with the process calibrator A (4). The pressure calibrating module is formed by a pressure connecting flexible tube (5), a pressure module (6) and a process calibrator B (7), wherein one end of the pressure connecting flexible tube (5) is connected with an input end of the pressure module (6), and an output end of the pressure module (6) is connected with the process calibrator (7). The online calibrating device is capable of realizing online calibration of the steam flow measuring system, increases production efficiency and reduces equipment investment cost.

Description

The on-line calibration device of perforated plate-type steam flow measurement system

Technical field

The utility model relates to flow apparatus collimation technique field, relates in particular to a kind of calibrating installation of steam flow measurement system.

Background technology

Perforated plate-type steam flow measurement system claims differential pressure flowmeter again, and system is made up of orifice plate, connecting pipe, differential pressure transmitter, pressure unit, integrating instrument and display.System promptly draws each parameter value on classical flow equation the right by measuring respectively, calculate and tabling look-up by the measurement of indirect metering system realization steam flow, carries it into classical flow equation then, calculates the flow of being surveyed, and is shown by display.Since being born from perforated plate-type steam flow measurement system so far, become present utilization the most extensive, install quantity at most, utilization steam flow measurement system with the longest history, it is extensive use of in all conglomeraties such as tobacco, electric power, metallurgy, chemical industry.

Mainly there is following problem in existing perforated plate-type steam flow measurement system: (1) need be made regular check on orifice plate and safeguard (because the orifice plate dismounting comparatively bothers, usually enterprise all is to use the several years just once to check maintenance, and this makes it become one of the measurement result accuracy factor that influences); (2) system in order to eliminate measuring error, needs respectively differential pressure transmitter, pressure unit and integrating instrument to be unloaded from system after using certain hour, send laboratory (need send relevant testing agency to the enterprise that does not have detection capability) to calibrate.Above factor all need be shut down operation, thereby has influenced production efficiency, has increased production cost.In order to make the perforated plate-type steam flow measurement system device therefor between alignment epoch, do not influence normal production, producer is toward living to need the configuration spare part, wherein pressure unit needs thousands of units, differential pressure transmitter to need thousand yuan of 3-4, a cigar mill that produces 1000000 casees per year just need be equipped with nearly hundred of differential pressure transmitter and pressure units, has increased its cost of investment undoubtedly.

Summary of the invention

The purpose of this utility model is to overcome above-mentioned shortcoming and a kind of on-line calibration that can realize the vapor flow rate measuring system is provided, and has improved production efficiency, has reduced the on-line calibration device of the perforated plate-type steam flow measurement system of equipment investment cost.

The on-line calibration device of perforated plate-type steam flow measurement system of the present utility model, comprise differential pressure calibration module and pressure calibration module, wherein: the differential pressure calibration module is made of with differential pressure transmitter, process checking gauge A high-pressure hose, low-pressure hose, calibration, high-pressure hose one end is connected with the high pressure feed of calibration with differential pressure transmitter, low-pressure hose one end is connected with the low pressure input port of calibration with differential pressure transmitter, and calibration is connected with process checking gauge A with the delivery outlet of differential pressure transmitter; The pressure calibration module connects flexible pipe, modular pressure and process checking gauge B by pressure and constitutes, and pressure connects flexible pipe one end and is connected with the input end of modular pressure, and the output terminal of modular pressure is connected with process checking gauge B.

The utility model compared with prior art, have the produce effects fruit is significantly arranged, by above technical scheme as can be known, procedure inspection instrument A shows that differential pressure value Δ P, the procedure inspection instrument B of differential pressure transmitter input show the pressure value P of modular pressure input, and the dynamic of these two parameters directly measured and calculated flow value and show that flow compares with institute's measured value.Instrument and equipment with maturation combines a kind of pick-up unit that detects perforated plate-type steam flow measurement system.Solve the accurate measuring problem of steam flow in the energy-saving and cost-reducing work, onlinely directly steam flow measurement system has been calibrated, improved the accuracy of the steam flow of measuring, realized the online in real time calibration; Online dynamic calibration does not simultaneously influence production, has removed to examining the indispensable fund that spare part overstock of standard; This apparatus structure is simple, price is lower, has good application and promotion prospect; Data are directly perceived, and calibration is quick, simple.Can be widely used in the detection system (promptly can be applicable to the differential pressure of boiler shop and the on-line calibration of pressure and Displaying Meter) of differential pressure mode sensed water level and discharge, pressure.

Description of drawings

Fig. 1 is a structural representation of the present utility model;

Fig. 2 is user mode figure of the present utility model.

Mark among the figure:

1, high-pressure hose, 2, low-pressure hose, 3, the calibration differential pressure transmitter, 4, process checking gauge A, 5, pressure connection flexible pipe, 6, modular pressure, 7, process checking gauge B.

Embodiment

The on-line calibration device of perforated plate-type steam flow measurement system, comprise differential pressure calibration module and pressure calibration module, wherein: the differential pressure calibration module is by high-pressure hose 1, low-pressure hose 2, calibration differential pressure transmitter 3, process checking gauge A4 constitutes, high-pressure hose 1 one ends are connected with the high pressure feed of calibration with differential pressure transmitter 3, the other end is used to connect the high pressure sewage draining exit of the differential pressure blow-off pipe of steam flow measurement system, low-pressure hose one end is connected with the low pressure input port of calibration with differential pressure transmitter 3, the other end is used to connect the low pressure sewage draining exit of the differential pressure blow-off pipe of steam flow measurement system, calibration is connected with process checking gauge A4 with the delivery outlet of differential pressure transmitter 3, and procedure inspection instrument A shows the differential pressure value Δ P of differential pressure transmitter input; The pressure calibration module connects flexible pipe 5, modular pressure 6 and process checking gauge B7 by pressure and constitutes, pressure connects flexible pipe 5 one ends and is connected with the input end of modular pressure 6, the other end is used to connect the pressure sewage draining exit of the pressure blow-off pipe of steam flow measurement system, the output terminal of modular pressure 6 is connected with process checking gauge B7, and procedure inspection instrument B shows the force value of modular pressure input.

With raw silk workshop section of calibration Guiyang Tobacco Factory steam flow check point is example, and its on-line calibration method is as follows:

(1) compensation flap on the equalizing valve of perforated plate-type steam flow measurement system is opened, made height pressure side equipressure;

(2) close high-pressure side valve and low pressure end valve on the equalizing valve, open pressure sewage draining valve, high pressure sewage draining valve and the blowdown of low pressure sewage draining valve respectively, after blowdown finishes, close above-mentioned three valves;

(3) high-pressure hose 1 of the present utility model is connected with the high pressure sewage draining exit of the high pressure blow-off pipe of steam flow measurement system, low-pressure hose 2 is connected with the low pressure sewage draining exit of the low pressure blow-off pipe of steam flow measurement system, pressure connects the pressure sewage draining exit of flexible pipe 5 and the pressure blow-off pipe of steam flow measurement system;

(4) treat to be full of condensate water in each blow-off pipe after, with verification with the Exhaust Open on the differential pressure transmitter, open high pressure sewage draining valve and the exhaust of low pressure sewage draining valve then simultaneously, after making the exhausr port drainage water of differential pressure transmitter, close the exhausr port of differential pressure transmitter, compensation flap on the equalizing valve valve body is closed, make equalizing valve return to duty, just can measure after waiting for about 30min system stability;

(5) read differential pressure value, force value respectively at process checking gauge A, process checking gauge B, read the demonstration flow value of perforated plate-type steam flow measurement system simultaneously synchronously; The time of reading is 5-30min, can calculate mean value separately respectively to read 30 data or more data at interval arbitrarily during this period, goes out the flow value of calibration equipment and the flow value of perforated plate-type steam flow measurement system with mean value calculation, by $Q=k\sqrt{\mathrm{\ρ\ΔP}}$ Calculate the flow of perforated plate-type steam flow measurement system and the deviation of design discharge.

Classical flow equation is as follows:

$Q=\frac{c}{\sqrt{1-{\mathrm{\β}}^4}}\mathrm{\ϵ}{A}_0\sqrt{2\mathrm{\ρ\ΔP}}$

Develop outflow according to classical flow equation and calculate experimental formula:

$Q=k\sqrt{\mathrm{\ρ\ΔP}}$

According to designing unit " calculated description ", check in: k=0.4056937.

Detect data such as following table (the unit difference in the form, it is different with the working range of differential pressure to characterize pressure):

Looking into the saturated vapor density table gets:

When absolute pressure was 1.174641MPa, saturated vapor density was 6.003;

When absolute pressure was 1.201020MPa, saturated vapor density was 6.132.

By interpolation arithmetic, in the time of can getting relative pressure 1.108MPa, when absolute pressure was 1.1974MPa, saturated vapor density was: 6.114.

With differential pressure 1.797kpa, density 6.114, k=0.405693 revises original system according to the result for as shown in the formula the flow value that can draw detection.

$Q=k\sqrt{\mathrm{\ρ\ΔP}}=1.345t/h$

The above, it only is preferred embodiment of the present utility model, be not that the utility model is done any pro forma restriction, any technical solutions of the utility model content that do not break away from,, all still belong in the scope of technical solutions of the utility model any simple modification, equivalent variations and modification that above embodiment did according to technical spirit of the present utility model.

Claims (1)

1. the on-line calibration device of a perforated plate-type steam flow measurement system, comprise differential pressure calibration module and pressure calibration module, it is characterized in that: the differential pressure calibration module is made of with differential pressure transmitter (3), process checking gauge A (4) high-pressure hose (1), low-pressure hose (2), calibration, high-pressure hose (1) one end is connected with the high pressure feed of calibration with differential pressure transmitter (3), low-pressure hose one end is connected with the low pressure input port of calibration with differential pressure transmitter (3), and calibration is connected with process checking gauge A (4) with the delivery outlet of differential pressure transmitter (3); The pressure calibration module connects flexible pipe (5), modular pressure (6) and process checking gauge B (7) by pressure and constitutes, and pressure connects flexible pipe (5) one ends and is connected with the input end of modular pressure (6), and the output terminal of modular pressure (6) is connected with process checking gauge B (7).

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