Explosion-proof gas turbine flowmeter

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ZW - LWQ seriesExplosion-proof gas turbine flowmeterUSES the advanced ultra low power single chip mi…

ZW - LWQ seriesExplosion-proof gas turbine flowmeterUSES the advanced ultra low power single chip microcomputer technology of turbine flow sensor and display integration of integrating new intelligent instrument, the double row at the scene of the liquid crystal display, with compact bodies, intuitive and clear reading, high reliability, without external power supply interference, lightning resistance, low cost, obvious advantages.Instruments have instrument coefficient of correction at six nonlinear intelligent compensation coefficient, and on-site correction.High-definition LCD display (four significant figures) instantaneous flow and cumulative flow (eight significant figures, with reset function).All valid data after 10 years is not lost when power supply drop.

Second, the working principle:
ZW - LWQ seriesExplosion-proof working principle of gas turbine flowmeter is a fluid flowing through the sensor shell, as a result of the impeller blade and flow to a certain point of view, the impact of fluid blade with rotational torque, to overcome the friction torque and fluid resistance, blade rotation speed stability after the moment balance, under certain conditions, the speed is proportional to the velocity of flow, because there are magnetic conductivity blade, it is in the signal detector (composed of * magnetic steel and coil) magnetic field, rotating blade cutting lines, periodically changing coil magnetic flux, so that the coil ends induction electrical pulse signal, the signal after amplifier amplification plastic, form a certain amplitude of continuous rectangular pulse wave, can be spread far to display instrument, show the instantaneous flow and cumulative amount of fluid.Within the scope of a certain flow, pulse frequency f and flows through the sensor of fluid is proportional to the instantaneous flow rate Q, flow equation is: Q = 3600 x f/k;Type:
F - pulse frequency (Hz);
K - the instrument coefficient of sensor 1 / m3, given by the check list.If [1 / L] as the unit
Q - fluid transient flow (working conditions) (m3 / h),
3600 - conversion factor.
Coefficient of each sensor of the instrument in the calibration certificate will be completed by the manufacturer, set into the display instrument of form a complete set of k value, can show the instantaneous flow and cumulative total.
Applications:
ZW - LWQ seriesExplosion-proof gas turbine flowmeter is a kind of precise flow measuring instrument, integrated turbine flowmeter for explosion-proof design structure, suitable for measuring the low viscosity of medium, such as water, diesel, gasoline, etc.With the corresponding flow integrating instrument can be used to measure the rate of flow of fluid and the total amount.Widely used in petroleum, metallurgy, scientific research in the areas of measurement and control system.
Four, the main features:
1, high accuracy, plus or minus 1%, plus or minus 0.5%, plus or minus 0.2%.
2, good repeatability, short-term repeatability could reach 0.05% ~ 0.2%, is a preferable flow meter in trade settlement.
3, the output pulse frequency signal, is suitable for the total measurement and computer connection, no zero drift, strong anti-jamming capability.
4, can obtain very good frequency signal (3-4 KHZ), strong signal resolution.
5, the structure is compact and lightweight, easy installation and maintenance, the flow capacity is big.
6, suitable for high voltage measurement, instrument on the table without hole, easy to made into high pressure type instrument.
Five, the technical parameters:
Meter diameter: threaded connections: 4, 6, 10, 15, 20, 25, 32, 40;
Flange connection: (15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200;
Insert: more than 200;
Range than: ";1:15.1;
Instrument material: stainless steel 304, 316 (L) stainless steel, etc;
Medium temperature: - 20 ℃ ~ + 120 ℃;
Ambient temperature: - 10 ℃ ~ + 55 ℃;
Relative humidity: 5% ~ 9%;
The atmospheric pressure: 86 ~ 106 kpa;
Output signals: sensors: pulse frequency signal, low level high level 8 V or 0.8 V or less;
Transmitter: two wire system 4-20 ma current signal or 1-5 v voltage signal;
Power supply: sensors: + 12 VDC and + 24 VDC transmitter: + 24 VDC site shows: instrument with lithium batteries;
Explosion-proof forms: basic not explosion-proof, explosion-proof type;
Protection grade: IP65, IP67.
Six, structure and installation method:
1, instrument installation using thread connection and clamp type;
2, liquid flow direction when installation should be direction of arrow and indicating flow sensor shell, and a straight pipe upstream should be 6 D, or downstream straight pipe should be 5 D or higher measured pipeline measured diameter (D).
3, sensors should be far away from the external magnetic field, such as can't be avoided, necessary measures should be taken;
4, in order to not affect the normal delivery of the liquid, maintenance should be straight section on opposite sides of the sensor installation outside the by-pass pipe;
5, sensors, outdoor installation time, please prepare amplifier plug waterproof processing;
6, sensor and display instrument connection, should according to the power of the amplifier to choose connection mode, as shown in the relevant specification.
Seven, wiring and grounding considerations:
Wiring matters needing attention
1, using a full cable as soon as possible.
2, should as far as possible away from electrical noise (such as power transformer, electric motor and the power cord), avoid parallel to the power the power cord wiring.
3, Suggestions in the end of the thick wire adopts the tin welding clamping lugs.
4, for the waterproof and mechanical damage, the cable into the metal tube inside, but may not have high power transmission cables, within the same catheter (a transmission cable transmission of zui power is greater than the flowmeter signal transmission cables zui small power 10 times, both cannot be installed on the same catheter).
5, the existing strong magnetic field outside the area, should make the axis of the detection device with the outside world vertical or the direction of the magnetic flux of the magnetic field with high permeability material for shielding flow sensor or external magnetic source.
6, explosion-proof type turbine flow sensor cable connection, must strictly abide by the relevant standards of explosion-proof amplifier.
Grounding problem
1, the shielding wire can only be grounded at one end, on display instrument grounding.
2, reliable grounding should be good, explosion-proof type grounding resistance should be less than 10 Ω.
The use of turbine flow time must pay attention to the points:
1, requires clean measured medium, low viscosity, corrosion resistance is small, do not contain impurities, in order to reduce the wear of bearing.If the liquid to be measured a grudge or containing gas, the flowmeter before venting device.In order to avoid damage of impurity in the fluid into the transmitter devious, and in order to prevent turbine stuck, add filters when necessary.
2, the installation of the flowmeter should avoid vibration, avoid magnetic field and thermal radiation.
3, medium density and viscosity changes have an impact on flow value, should be revised if necessary.
Eight, the installation place:
1, the installation site should comply with the environmental temperature at 25 ~ 55 ℃ scope, humidity < 80% RH;
2, well ventilated, avoid sun and rain;
3, avoid in piping vibration or the place of stress;
4, avoid easily affected by the strong thermal radiation and radioactive places;
5, must avoid the outside strong electromagnetic field disturbance to the detection signal.If unavoidable, should be set on the amplifier of the flowmeter (sensor) shield and other measures to eliminate interference;
6, in the places where requires explosion-proof, and isolation amplifier should be adopted;
7, the installation position should consider ease of installation, operation, maintenance.
Nine, installation reasons may lead to the problem:
1, the length of straight pipe upstream or downstream is insufficient;
2, instrument measuring pipe diameter and pipe diameter deviation;
3, install different heart, gasket convex tube;
4, instrument going backward;
5, detecting element is covered by impurities;
6, reduce the detection sensitivity, small leakage flow meter;
7, pipeline leak (installed in underground pipeline, for example, small leakage was found), valve leakage, by-pass valve leakage cause cumulative flow smaller (total);
8, there are two phase flow, pulsating flow influence the accurate measurement.
Ten, must pay attention to when using:
1, requires clean measured medium, low viscosity, corrosion resistance is small, do not contain impurities, in order to reduce the wear of bearing.If the liquid to be measured a grudge or containing gas, the flowmeter before venting device.In order to avoid damage of impurity in the fluid into the transmitter devious, and in order to prevent turbine stuck, add filters when necessary.
2, the installation of the flowmeter should avoid vibration, avoid magnetic field and thermal radiation.
3, medium density and viscosity changes have an impact on flow value, should be revised if necessary.

Eleven, parameter table:

Twelve, measurement range and pressure rating:

13, selection of coding:

For example, the model is:ZW-LWQ－C－50－B－A-AThe gas turbine flowmeter, said:
Meter diameter for50mm, display and output way of live shows, the output current for measuring precision1.0%;Turbine types are measured normal flow range of intelligent explosion-proof type gas turbine flowmeter.

14, 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, 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.