High pressure type vortex precession flowmeter

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ZW series - LUXHigh pressure type vortex precession flowmeterIs a new kind of gas flow meter has the…

ZW series - LUXHigh pressure type vortex precession flowmeterIs a new kind of gas flow meter has the domestic advanced level.Set the flowmeter flow, temperature, pressure testing function can be in the work of the squeezing factor of temperature, pressure, automatic compensation, precession vortex gas meter in the measurement signal as well as local display, can also be on-demand far eastone, have no moving parts, so for the average measurement is no mechanical wear, instrument management personnel without professional training, flow, pressure and temperature were measured and parameters can be read directly from the header and don't have to translate transformation;Electromechanical integration is realized.

Second, the working principle:

ZW - LUX series high pressure type vortex precession flowmeter is when a fluid through a helical vane vortex generator, composed of fluid is forced to around the dramatic rotating body axis, the formation of vortex.When fluid into the diffuser, vortex flow under the effect of reflux, began as a secondary rotation, form the gyro type vortex precession phenomenon.The precession frequency is proportional to the flow size, not influenced by the physical properties and fluid density.Detecting element quadratic spin precession frequency measured fluid, knew the traffic.And in a relatively wide flow rate range for good linearity.Flowmeter formula is: K = f/q

Type: K - l/m&sup 3 flow meter coefficient

F - vortex frequency Hz

Q - volume flow m&sup 3;/ s

The instrument coefficient of flow meter in certain structural parameters and the specified within the scope of Reynolds number and the fluid temperature, pressure, composition and physical properties (density, viscosity) has nothing to do.

Applications:

ZW - LUX series high pressure type vortex precession flowmeter using new micro processing technology, has the function of strong, wide flow rate range, simple operation and maintenance, and convenient to install and use etc, and the main technical indexes reach the advanced level of the same products abroad.It is widely used in petroleum, chemical industry, electric power, metallurgy, coal, etc all kinds of gas measurement.

Four, vortex precession flowmeter by the following seven basic parts (figure 1) :

Precession vortex flowmeter structure

1, vortex occurred

Made of aluminum alloy, with a certain Angle spiral blade, it is fixed at the front of the housing contraction, forcing fluid produced strong vortex flow.

2, shell

Itself with the flange, the shape of the fluid channel and to a certain extent, according to the different working pressure and shell material can be cast aluminum alloy or stainless steel.

3, intelligent flowmeter integrating instrument

By the temperature, pressure testing analog channel, flow digital channels and micro processing unit, LCD driver circuit and other auxiliary circuit composition, and equipped with transmission signal interface.

4, temperature sensor

Pt100 / pt1000 platinum resistor as the temperature sensitive element, in a certain temperature range, the resistance value and temperature into corresponding relation.

5, pressure sensor

With diffused silicon piezoresistive type bridge road as the sensitive element, the bridge arm resistance will happen under outside pressure is expected to change, therefore under certain excitation current, its two outputs potential difference is proportional to the pressure.

6, piezoelectric crystal sensors

Near the shell expansion period of throat, can detect the frequency signal of vortex precession.

7, disappear is investigated

Fixed in the shell outlet, its function is to eliminate vortex flow, to reduce the impact on downstream instrument performance.

Five, the meter is composed of sensor and conversion display.

1, sensors, including vortex generator, detecting element, rectifier and shell.

Vortex generator is composed of specific spiral blade, it fixed in the housing contraction front, forcing fluid produced strong vortex flow.

The throat of detecting element near the expansion pipe with thermal, piezoelectric, strain, or optical detecting element to measure the frequency signal of vortex precession.

Rectifier is fixed in the meter body exports, its function is to eliminate vortex flow, to reduce the influence of downstream flow pattern for instrument measurement.

Shell design into a certain shape of flow channel, to form vortex, fixed and protection is installed in the internal parts and components, and by pipeline flange connection.

2, transform, display

By piezoelectric sensors detect the weak voltage signal after amplification, filtering, plastic into frequency is proportional to the flow of the pulse signal, and then by the display counter.Display is equipped with a transmission interface, the output signals.To measure gas medium temperature and pressure compensation, can be converted into standard volume flow conditions, and display.

3, the structure composition:

ZW - LUX series compact structure, and is mainly composed of shell, the vortex occurred body, sensors (temperature, pressure, flow), rectifier, bracket and converter.

Six, the main features:

1, built-in pressure, temperature, flow sensor, safety performance is high, compact structure, beautiful appearance;

2, in situ show that temperature, pressure, the instantaneous flow and cumulative flow;

3, a new signal processing amplifier and unique filtering technology, effectively eliminate the pressure fluctuation and pipeline vibration produced by the jamming signal, greatly improve the anti-interference ability of the flowmeter, small flow have excellent stability;

4, the characteristic time display and real-time data storage function, no matter what circumstance, can guarantee the internal data is not lost, may be retained * sex;

5, the machine power consumption is extremely low, can run on battery power for a long time in, is the ideal without external power supply on-site display instrument;

6, anti-theft functions and reliable, with password protection, prevent parameter changes;

7, free rotation headers can be 180 degrees, convenient installation.

Seven, the technical parameters:

1, flowmeter specification, basic parameters:

Note: a. the flow range of products listed in the table when the verification of the flow range (temperature, air pressure medium for P = 1.205 Kg/m3);B. with the increase of pressure, flow range is expanding.

2, the standard state situation: P = 101.325 kPa, T = 293.15 K;

3, the conditions of use:

A, environmental temperature: - 30 ~ + 60 ℃;

B, medium temperature: - 20 ~ + 80 ℃;

C, relative humidity: 5% ~ 95%;

D, atmospheric pressure: 86 kpa to 106 kpa.

4, electrical performance indicators:

Outside a, working power supply: power supply: + 24 VDC;

B, within the power supply: 3.6 V lithium batteries;

C, the whole machine energy consumption: external power, < 1 w power supply, < 0.3 mW, lithium battery can be used at least 2 years;

D, the output mode: frequency signal;

: e, 4 ~ 20 ma current signal corresponding to the flow of 0 ~ Qmax, 20 ma, corresponding flow can be set by users themselves;

F, RS485 communication: can transfer temperature, pressure, the instantaneous flow and cumulative flow parameters;

5, explosion-proof marks: Exd Ⅱ BT4;

6, protection grade: IP65.

Eight, fault phenomenon and solution:

1 meter, flowmeter show temperature and pressure is normal, no instantaneous flow display

Reasons: (1) meter selection is too big, no flow selection will cause flowmeter.Solution: one is the lower limit cut-off frequency lower flowmeter (such flowmeter can be used, but will cause the meter accuracy reduce).2 it is to replace the small specification flowmeter.

(2) : no current input preamplifier.No power supply solution: flowmeter, flow meter for 24 v external power supply or batteries.

(3) : preamplifier output frequency.Replaceable preamplifier.

(4) : motherboard damage.Replaceable flowmeter motherboard.

2 meter, flowmeter, according to the temperature, transient flow with pressure and the actual work instructions

(1) : if the pressure value is indicated "80" or meter "maximum pressure" (upper limit within the flowmeter selection reference table) can be.Reasons: one is the external new pressure sensor, watching to see if the header according to the local atmospheric pressure, if according to the local atmospheric pressure, the damage of the original sensor.Can replace the pressure sensor.Second, external half new pressure sensor, if the header display is still the "80", the flowmeter motherboard bad.Replaceable flowmeter motherboard.

(2) : the pressure value for a certain value (header field work pressure change is bigger, flowmeter showed no changes or smaller pressure).Reasons: one is the pressure sensor hole blockage.Can take pressure hole cleaning.Secondly, the pressure sensor linear calibration curve becomes bad.Replaceable or to set pressure sensors.

3, the header display instantaneous flow rate and pressure is normal, temperature display and temperature field

(1) : temperature values for "- 75 - c" or more than 100 ℃.Reason: the temperature sensor is damaged.Replaceable sensor.

(2) : temperature exceeds or is lower than the actual temperature value, replace the sensor, still for the phenomenon.Reason: the damage of thermal pressure circuit.Replaceable thermal pressure circuit.

4, flowmeter no display meter

Reasons: (1) meter without 24 v power supply or batteries.To 24 v battery power supply or replace the flowmeter flowmeter.

(2) : flowmeter damage of LCD panels.Replace the flowmeter LCD panels.

(3) : flowmeter motherboard damage.Replace the flowmeter motherboard.

(4) : power supply connection bolt or mistake.Find and rewiring.

Nine, installation considerations:

Click the flow mark 1, sensors can be tilted in vertical, horizontal, or any location on the installation;

2, when the pipeline vibration source is longer or distance is relatively close, support should be installed at upstream or downstream of flowmeter, in order to eliminate the influence of the pipeline vibration;

3, sensor installation location should have enough space, so that the flow meter inspection and maintenance, and should meet the environmental requirements of flowmeter;

4, should avoid the disturbance of external magnetic field;

5, when used in outdoor installation, should have cover, avoid the strong sunlight and rain erosion, affect the service life of the instrument;

6, when the pipeline pressure testing, should pay attention to the configured intelligent flowmeter pressure pressure sensor measuring range, in order to avoid over-voltage damage pressure sensor.

Installed 7, should pay attention to stress, the effect of upstream and downstream piping flow meter should be coaxial, otherwise it will produce shear stress.The location of the installation flowmeter should consider the thickness of the sealing gasket, or install a elastic expansion joints in the downstream side.

Should be clear before 8, installation flow meter of the pipeline welding slag and other sundry.

9 and put into operation, should slowly open flowmeter, downstream of the valve, in order to avoid air flow is too sharp and blunt bad on the moment.

10, when the meter requires signal remote transmission, must be strictly in accordance with the requirements of "electrical performance indicators" access to the outside (8 ~ 24 VDC power supply, it is strictly prohibited in the direct access to 220 vac or 380 vac signal output power;

11, the user may not change the connection mode of explosion protection system and arbitrary twisted each output pin connector;

12, flow meter is running, not allowed to open the rear cover change instrument parameters, otherwise the normal operation of the meter;

13, regularly check the flowmeter flange leakage situation.

Ten, flange connection size:

Eleven, selection of coding:

Twelve, designing order selection guidelines:

1, instrument selection, as far as possible not to use the work flow in the lower limit value, so the meter diameter should be as small as possible, in order to obtain a larger flow rate and flow range.

2, the flowmeter should be used in the technical parameters of medium pressure and temperature range.Don't deliberately choose the high pressure level and ultra-high temperature instrument, should be selected according to the actual work pressure and temperature instruments, which had higher prices.

3, in the explosive dangerous location, should choose explosion-proof type flowmeter.

4, the lower limit of flowmeter flow depends on the operation condition of the medium density and kinematic viscosity, the maximum flow is generally not affected by medium pressure and temperature, so to determine the flow range as long as you determine the actual minimum flow can be available.Calculate the minimum flow rate, flow range check table to determine the appropriate diameter.

After-sales service commitment:

1, our company sold by flow meter series products within twelve months appear quality problem, is responsible for free maintenance.

2, the warranty period, any quality problems such as the products of our company, my company is responsible for free repair or replacement.

3, the warranty period, such as user improper use, damaged products, my company is responsible for the maintenance, charge damage parts cost.

4, after the warranty period appear quality problem, my company is responsible for the maintenance, charge damage parts cost.

5, such as user need to my company site services, to users in the province I company service personnel to reach the site within 12 hours, fujian association of foreign languages and user reach the site within 48 hours.