One-piece vortex flowmeter

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One-piece vortex flowmeter is mainly used for industrial piping medium fluid flow measurement, such …

Products overview:
ZW - LUGB seriesOne-piece vortex flowmeterHas a good adaptability, medium to measure directly need for temperature and pressure compensation is mainly used for industrial piping medium fluid flow measurement, such as gas, liquid and vapor, and other media.Is characterized by small pressure loss, wide range, high precision, working condition of the measurement volume flow is almost not affected by the fluid density, the influence of the parameters such as pressure, temperature, viscosity.No moving mechanical parts, so high reliability, small amount of maintenance.Instrument parameters can long-term stability, using piezoelectric stress sensor can work in - 20 ℃ ~ + 250 ℃ temperature range.There are standard signal simulation and digital pulse signal output, can be used with digital systems, such as computers, and is a more advanced, the ideal product.
Second, the working principle:
ZW - LUGB seriesOne-piece vortex flowmeter in the measuring tube vertically inserted a pillars, on both sides of the fluid through the pillars is alternately with the rules of the vortex, the spiral column is called the karman vortex street.The release of the karman vortex street frequency is related to the width of the fluid velocity and pillars, expressed by the type:
f＝St·v/d 
Type: - the release of the karman vortex street frequency f
St - coefficient (called, ha)
V - velocity
D - the width of the pillars
Karman vortex street release frequency f and is directly proportional to the velocity v, so by measuring the karman vortex street release frequency to calculate the instantaneous flow rate.
Stern lo ha is one of the important coefficient of vortex flowmeter.In its number of St 0.17 straight part of the material, the release of the vortex frequency is proportional to the velocity of flow, so check out the velocity v, frequency f can be obtained to calculate volume flow by v.
Vortex flow sensor be vortex frequency is applied to detect sensor by vortex alternately (probe) on in-situ stress in its internal piezoelectric element to check out.
Applications:
ZW - LUGB seriesOne-piece vortex flowmeter is a kind of flow meter with a broad range of USES, for the vast majority of steam, gas and liquid flow measurement, measurement, control, widely used in petroleum, chemical industry, metallurgy, electric power, papermaking, pharmaceutical, food industries and municipal construction, environmental protection engineering and other industries.
Four, the main features:
1, no moving parts, long-term stability, the structure is simple and easy to install and maintain.
2, sensor output pulse frequency, the frequency and the actual flow into linear flow body, zero drift, performance is very stable, structure forms, pipeline, plug flow sensor.
3, high precision, long gas measurement accuracy of 1.5%.
4, wide measuring range.
5, small pressure loss, belong to the energy flow meter.
6, flexible installation, according to the process piping is different, can be horizontal, vertical and inclined Angle of installation.
7, the instrument can be widely used, saturated compressed air and superheated steam, gas and all kinds of medium flow rate measurement.
Five, the technical parameters:
1, the measured medium: gas, liquid and vapor;
2, connection mode: flange card mounted, flange, plug-in;
3, diameter specifications flange mounted caliber select 25,32,50,80,100;
4, the flange connection type choose 100150200;
5, flow range (see chart flow range)
6, normal measuring velocity range Reynolds number 104 ~ 1.5 x 4 x 106;Gas 5 to 50 m/s;Liquid 0.5 ~ 7 m/s;
7, measurement accuracy 1.0 magnitude 1.5 on the Richter scale;
8, measured medium temperature: room temperature - 25 ℃ ~ 100 ℃, high temperature - 25 ℃ ~ 150 ℃ to 25 ℃ ~ 250 ℃;
9, high output signal pulse voltage output signal level 8 ~ 10 V low level from 0.7 V to 1.3 V;
10, pulse duty ratio is about 50%, transmission distance is 100 m;
11, pulse current 4 ~ 20 mA remote transmission signal, transmission distance is 1000 m;
12, instrument: using the environment temperature 25 ℃ ~ + 55 ℃, humidity: 5 ~ 90% RH50 ℃;
13, the material of stainless steel, aluminum alloy;
14, DC24V power supply or lithium battery 3.6 V;
15, explosion-proof grade this Ann model iaIIbT3 - T6, protective class IP65.

Six, appearance size:

Seven, pipe requirements:
1, the requirement for straight pipe:
In order to ensure that the instrument, accurate to run normally, sensor must have a certain straight pipe upstream and downstream of the installation points, to adjust the flow field, as shown.

Figure 1: concentric contraction tube;
Figure 2: the concentric expansion tube;
Figure 3: a 90 - degree Angle;
Figure 4: the same plane of two 90 - degree Angle;
Figure 5: different plane of two 90 - degree Angle;
Figure 6: regulating valve should be installed downstream of the sensor in 5 d to the distance, if the sensor must be installed in the upstream, the sensors should be not less than 50 d upstream, straight pipe section downstream straight pipe section should be not less than 5 d.
2, the requirement of pipe:
A, upstream and downstream piping diameter D and the same as the sensor inner diameter DN, its difference satisfy the following conditions: 0.95 DN D 1.1 or less or less DN.
B, piping shall be concentric with sensor, coaxial degree should be less than 0.05 DN.
C, gasket not protruding into the pipe, the inner diameter slightly larger than sensors.
D, if you want to stop inspection and cleaning the sensor, the by-pass pipe should be set up,As shown in the figure below.

 
3, the requirement of pipe vibration:
Sensors to avoid installed on the strong pipeline vibration, if necessary to install, shock absorption measures must be taken, respectively at the upstream and downstream of sensor 2 d piping fastening device, and vibration-proof pad.
Special note: in the air compressor exit strong vibration, cannot install the sensors, shall be installed after the gas storage.
4, demand for air condition:
A, the gas to be tested for single phase pipe flow, continuously flowing through a pipe.
Before b, the gas flows through the flowmeter, the flow rate must be parallel to the pipe axis, can not have vortex flow.
C, flow should be a subsonic, a pulse, its flow change slowly over time.
5, the flowmeter installation requirements:
Vortex street flowmeter to process the installation and use of the special requirements of environment is not too much, but any kind of flow measurement instrument has such a common, as far as possible to avoid vibration and high temperature environment as flow interference elements (such as compressor, separator, pressure regulating valve, reducer, and pipe, elbow, etc.), keep straight pipe before and after the instrument inside sleek straight, ensure to clean single-phase fluid measured medium, etc.

Eight, installation environment requirements:
1, as far as possible to avoid the high voltage equipment, high-frequency equipment, switching power supply equipment.Instrument of power supply from these devices as much as possible.
2, avoid high temperature heat source and the radiation source.If you have to install, you must have heat ventilation measures.
3, to avoid the high humidity and strong corrosive gas environment.If you have to install, you must have ventilation measures.
4, vortex flow meter should be avoided to install on the strong vibration of pipeline.If you have to install, you must set up at the upstream and downstream 2 d pipeline fastening device, and vibration-proof pad, strengthen the effects of vibration resistance.
5, instrument installation installed indoors, outdoors should pay attention to waterproof, pay special attention to in the electrical outlet cables should be bent into a U shape, avoid water along the cable into the amplifier shell.
6, instrument installation point should have a plenty of space around, in order to install the wiring and regular maintenance.
Nine, field requirements:
1, low maintenance - most of the vortex flowmeter are on the market with induction swirl hole or plug-in measurement, once the impurities embedded in the medium pressure hole or sensing element and the table body, the gap between the signal is weak or unstable.A good design should be not easy to plug part, thereby reducing amount of maintenance.
2, inductive components online replacement - some manufacturer of inductive components and vortex street close 2 for one, seemingly simple design to the actual use of inconvenience.Because once induction part failure, you need to medium to the pipe emptying replacement parts, after pressure relief effect production.Perfect design should be separated the two, so can replace the induction part alone, without emptying the media.
3, vortex flowmeter is vulnerable to vibration interference, well-designed vortex flowmeter can through hardware and digital signal processing to exclude interference, and the stability of the signal is obtained.
4, vortex flow meter before and after the installation of a hassle to very long straight section, some manufacturers can offer within the flowmeter reducing design, greatly reduces the user specifically MenWei vortex flowmeter with the demand of the straight pipe.
Ten problems need to pay attention to during using, debugging:
1, flowmeter, on-site installation, maintenance, must abide by the "explosion-proof gas do not open" warnings, and in the open before turn off the power supply.
2, vortex flow meter used in outdoor, suggestion and side shields.
3, shall not be arbitrarily fixed part loosen the flowmeter.The protection of the pressure sensor.Users in the use of traffic time, should pay attention to the flow pressure overload value of pressure sensor is rated working pressure of 1.5 times (that is, the media zui high pressure of 1.5 times).Selection should be within the prescribed flow range, prevent overspeed operation, in order to obtain the ideal accuracy and ensure the normal service life.(due to pressure test, purging pipes or exhaust overdrive, and turbine operation in the reverse flow meter can cause damage)
4 when put into operation, the vortex street flowmeter, should slowly open valve, prevent damage of instantaneous flow and the turbine.Add lubricant should be according to the sign, the number of refueling depends on temperament clean degree, usually 2 ~ 3 times a year.
5, vortex street flowmeter runtime or alternate internal related parameters are not allowed to open the rear cover, otherwise will affect the normal operation of the meter.
Eleven, install and use should be paid attention to in the items:
Vortex street no mechanical moving parts, small size, corrosion resistance, stable performance, can be directly display medium work pressure, temperature, flow rate and volume under standard state, wide range, the advantages of small measurement error, has been widely used in oil and gas well production measurement and gas sales.In years of field application, we think the flowmeter zui suitable for relatively clean dry gas metering, gradually become small and medium-sized gas metering.To guarantee the accuracy of the flowmeter measurement, reduce the measuring error, please note:
1, the selection of reasonable
Don't make the actual zui small flow meter QVmin below the selected through runoff flow range limit.
2, installation is correct
Upstream of the vortex flowmeter should have at least 10 d measuring straight pipe length.Straight pipe inner surface should be smooth, cannot have the steps, more smooth connecting flange weld, flange gasket can't into the pipe.Don't put the wrong installation direction of the flow meter.Tests showed that: all the unreasonable installation, will lead to the flowmeter measurement value is low.
3, away from the source of shocks, or install piers in upstream or downstream flow meter, in order to avoid the influence of the pipeline vibration.Avoid strong magnetic field disturbance to the flow meter chip.
4, temperament is relatively clean
Especially not a gas liquid two phase flow;Temperament is dirty, should clean instant flow meter.
5, and reduce the influence of flow pulsation
It can be installed in front of the flow meter buffer tank, or extended length of straight pipe upstream of the flow meter, computation.
6, timely flowmeter for metrological verification, to ensure accurate and reliable value.
Twelve, matters needing attention:
1, special flange and straight pipe welding can't with the sensor.
2, when installation should make the flow of sensor mark the direction of flow and the pipe.
3, before the installation of sensor and the flange must be put away in sealing ring grooves.The location of the pressure and temperature measurement point, pressure downstream of the sensor in 3 ~ 5 dn, temperature measuring points in the downstream of 5 ~ 8 dn.
4, when measuring high temperature medium, do not use heat insulation material to wrap around the sensor link rod.
Five, connection of shielded cable, should as far as possible away from the interference of strong electromagnetic field.Absolutely not allowed with high voltage cable laying, shielded cable to shorten as far as possible, and shall not be volume, in order to reduce stray inductance, length should not exceed 200 m.
6, before installation of sensors, pipeline cleaning must be conducted.Flow after rinse tube impurities, avoid clogging sensor.Measuring liquid pipe must be full of measured liquid, prevent the interference of bubbles.
7, measuring gas pipelines to prevent the interference of reservoir fluid.Installation position as shown in figure 5.Replace the probe body under the high temperature and high pressure, it must be safe operation, high temperature protection.After cooling step-down replaceable probe at the bottom of the safety conditions.

13, selection of points:
1, as far as possible not to use in the selection of flowmeter work flow in the lower limit value, so the meter diameter should be as small as possible, in order to obtain larger flow velocity 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 vortex street 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.

14, standard of flow range profile: unit (m3 / h)

15, selection of coding:

16,Order to choose selection guidelines:

Name and model number of 1, 1), (2) the diameter, flow range, (3) whether or not to bring the attached so that we can correct selection for you, (4) using pressure, (5) the use of medium temperature.

2, if has been selected by design units in the way of vortex street flowmeter types, please press type vortex flowmeter directly order from our sales department.

3, when using occasions is very important, or the environment is complex, please try to provide the design drawings and detailed parameters, by wei experts in our audit checks for you.

After-sales service commitment:

1, from the date of signing of the contract, I in the way provided for products of the company offers free maintenance and maintenance service, commitment to lifelong maintenance service;

2, jiangsu wei measurement and control instrument co., LTD. Sales manager will be in regular contact with customers, understand the usage of products, and solve the problems of the customers to use in the process of produce, free of charge to provide technical support;

3 the man-made damage is found, the warranty period, our company is responsible for the maintenance, and the resulting maintenance fee;

4, product quality problems or are not satisfied with product, the user can choose unconditional return, wei tt&c don't charge any fees, appear quality problem, bear the freight back and forth.