Stainless steel vortex flowmeter

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Stainless steel vortex flow meter adopts advanced technology, combined with isolation, shielding, fi…

Products overview:
ZW - LUGB seriesStainless steel vortex flowmeterIs the use of fluid vibration principle and development of a new type of flowmeter, adopts full stainless steel material.Widely used in petroleum, chemical industry, metallurgy, paper and other fluid measurement, the flowmeter have no moving parts, reliability, high precision, long life, can be in a very wide range of flow measuring precise instantaneous flow and cumulative flow of liquid.It is not affected by medium, the influence of temperature, pressure, viscosity and component without plugging, BuKa, not easy to scale formation, corrosion resistance, high temperature, high pressure safety explosion-proof, suitable for bad environment.Traffic integration of scoring display and remote transmission, and can output pulse signals or electric current signal and computer networking.

Second, the working principle:
ZW - LUGB seriesStainless steel 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 seriesStainless steel vortex flowmeter can be widely used in large, medium and small various water supply and drainage pipe, industrial circulation, sewage treatment, oil and chemical reagents and compressed air, saturation and superheated steam, gas and all kinds of medium flow rate measurement.
Four, the main features:
1, can measure the steam, gas, liquid and the volume flow to mass flow.
2, dismantling the can realize does not block the flow sensor, which can realize the amplifier and sensor separation (separation distance of 15 m).
3, USES the interference elimination circuit and anti vibration sensing head, make the instrument has certain environmental vibration resistance.
4, small pressure loss, wide range, range of 10 to 40 times.
5, no mechanical moving parts, long-term stability and simple structure is convenient for installation and maintenance.
6, measurable medium temperature up to + 350 ℃ (+ 450 ℃).
Five, the technical parameters:
1, the measured medium: liquid, gas, natural gas, steam (saturated steam and superheated steam);
2, measuring range: Reynolds number is 5 x 103 ~ 7 x 106
3, normal measuring range: Reynolds number is 2 x 104 ~ 7 x 106
4, measure velocity range: liquid 0.5 ~ 7 m/s gas 4 ~ 35 mm/s steam 7 ~ 70 m/s
5, by measurement of body temperature: - 40 ℃ ~ + 300 ℃
6, by measurement of body temperature: 1.6, 4, 25 mpa
7, accuracy: level 1, 1.5, 0.5 (by nonlinear dressing can reach 0.5);
8, repeatability: 0.2% of the indicated value;
9, table body materials: ICr18Ni9Ti;
10, the pressure loss: delta (r = 1.2 * 10-6 V2 type: delta r - P - pressure loss measured the fluid density (Kg/m3) v - tube average flow velocity (m/s) ambient temperature: - 20 ℃ ~ + 55 ℃ (special request order)
11, environment humidity: 90% RH or less
12, atmospheric pressure: 86-106 kpa
13, external power supply source: 3.6 ~ 224 VDC
Power source: within 14, 3 ~ 4.5 VVDDC
15, working power supply: 80 / A
16, working voltage: 2.7 ~ 3.6 v
17, working frequency: 0.1 ~ 3000 h
18, signal remote transmission distance: 100 mm
19, signal output: pulse output (power source) 4 ~ 20 madc output current (two wire system for 24 VDC power supply) pulse output and the output current can only choose one way.

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, selection of key 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.
Nine, installation requirements:
1, the sensor can be installed indoors, can also be installed in the outdoor.Environmental conditions to conform to the requirements.
2, sensors should be installed in a horizontal, vertical or inclined (fluid flow from bottom to top) and its corresponding pipe nominal diameter.
3, sensors installed on a mechanical vibration of pipeline should be avoided.Should be considered when the vibration is inevitable, at about 2 dn from sensor before and after the straight pipe and fixing racks.
4, avoid install the sensor sensing has strong electromagnetic interference, thermal radiation, corrosive gas, the space is little, and maintenance is not convenient.
5, when measured medium contains many impurities, at the request of straight pipe upstream from sensors mounted outside the length of the filter.
6, either upstream or downstream of the sensor should be configured with a certain length of straight pipe, straight pipe inner surface should be clean, smooth, no obvious convex concave, fouling and peeling phenomenon.Its length should conform to the requirements of figure 2.Installation of the liquid sensor, near the pipe should be filled with liquid to be tested.
7, straight pipe diameter as far as possible consistent with the sensor size, if not consistent, slightly larger diameter than the sensor size should be adopted, the error to 3% or less is not more than 5 mm.
Ten, 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.
During 11, debugging use need to be aware of problems:
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.

Twelve, install and use the items that should be paid attention to:
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 field application over the years, we believe that the meter is suitable for relatively clean dry gas metering, gradually become small and medium-sized gas meters.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.

13, the 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.

5, shielded cable to connect the sensor, 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.

Measuring gas pipeline to prevent reservoir fluid.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.

Installation of the normative management:

Vortex street flowmeter standard installation, to use the department in the subsequent management provide strong technical support, put forward the following specific requirements of the construction unit, after years of validation effect is very good.

1, with 4 ~ 20 ma output, pulse output.

2, GPRS remote transmission device with pulse input, input 4 ~ 20 ma.

3, with power supply prevents thunder and lightning protection (4 ~ 20 ma) signal.

4, instrument cabinets for: ark with UPS power supply, open and the socket, the GPRS communication devices, intelligent vortex flowmeter converter such as concentrated installation and lock.

5, smooth instrument ark need concrete pier base, instrument protection grade for outdoor cabinet, the ark with insulating layer to prevent sun point-blank, ark with water proof function.

6, domestic demand has left side table well enough straight pipe, facilitate intelligent vortex flowmeter test, compare and follow-up management.

7, the design of intelligent vortex flow timing front must have at least 10 times of nominal menstruation (dn) 10 straight pipe, the back-end must leave more than 5 dn straight pipe, to ensure accurate measurement.

8, shall be installed in accordance with the specifications and after the installation need measuring grounding, grounding resistance should be under 10 Ω.Equipotential connections using multiple strands of copper wires, cables should be greater than or equal to 16 was;Instrument grounding line using multiple strands of copper conductor, cable requirement was greater than or equal to 6.Grounding standard see GB50343-2009 "technical specification for building electronic information system lightning protection.

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

16, selection of coding:

17,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.