The tube flowmeter

Products overview:

ZW series of TBG toba tube flowmeter is suitable for gas, liquid and steam flow of high precision measurement.Toba tube is a differentia pressure, rate of average flow sensor, through the sensor in the fluid produced by the differential pressure flow rate measurement.Toba tube reflect the actual velocity of the fluid, and its accuracy is + / - 1.0%, repeatability of plus or minus 0.1%.Deere's prominent advantage is: the output is a very stable, no differential pressure signal of pulse.Continuous operation proved that the height of the toba tube design integrity, and with its easy installation, small pressure loss, high strength, is not affected by wear, no leakage characteristics become the alternative choice of orifice plate.

Second, the working principle:

ZW series - TBG toba tube flowmeter is when the fluid flows through the sensor, a high pressure generated in the front of its distribution area, hydrostatic pressure slightly higher than the area of high pressure pipe.According to the principle of Bernoulli equation, to speed up the speed when the fluid flows through the probe, the probe at the back of the produce a low pressure area, the pressure is slightly lower than area of low pressure pipe of the static pressure.Fluid from the probe through the vacuum on the probe at the back of the part, and appear on both sides of the probe vortex.Average flow cross section shape of probe, the condition of surface roughness and low pressure hole location is the key to probe performance factors.Low voltage signal is stable and accurate, is crucial to average probe of precision and performance.Pig, average flow probe can be detected accurately by the fluid produced by the average speed of the average differential pressure.Toba tube average flow probe in high and low pressure area according to certain criteria to take more pressure hole arrangement, made it possible to accurately measure the average velocity.

ZW series - TBG toba tube flowmeter is a kind of porous average flow velocity of design on the basis of the principle of uniform tube flowmeter, it produces a flow with direct ratio of the square of the average differential pressure (DP).In order to generate and flow proportional electrical signal, usually the DP output voltage signal with a guide tube coupled to the differential pressure transmitter.

Flow calculation formula:

Respectively, mass flow (㎏ / s) and volume flow (m3 / s);

- the average flow velocity;

- meter coefficient;

- flow coefficient;

-- the expansion coefficient;

- pipe diameter, m;

- the flow volume density, ㎏ / m;

-- differential pressure, Pa;

Applications:

1, the industrial production process

Is one of the categories of instruments for process automation instrument and apparatus, it is widely used in metallurgy, electric power, coal, chemical industry, petroleum, transportation, construction, textile, food, medicine, agriculture, environmental protection and People's Daily life and so on each domain of national economy, is the development of industrial and agricultural production, save energy and improve the quality of our products and improve the economic benefit and the management level of the important tools in the national economy occupies an important position.In process automation instrument and apparatus, flow instrument has two functions: as a process automation control system of the testing instrument and measuring the amount of material quantity table.

2, energy metering

Energy can be divided into primary energy (coal, oil, coal bed methane, liquefied petroleum gas (LPG), and natural gas), secondary energy (electricity, coke, artificial gas, refined oil, liquefied petroleum gas, steam) and can load working medium (compressed air, oxygen, nitrogen, hydrogen, water), etc.Energy metering is energy, scientific management to realize saving energy and reducing consumption, and an important means to improve the economic benefit.Flow meter is an important part of energy meters, water, artificial gas, natural gas, steam and oil these commonly used energy using a very large number of flow meter, which is an indispensable tool in energy management and economic accounting.

3, environmental protection engineering

Flue gas, liquid and solid sewage emissions serious air pollution and water resources, such as a serious threat to human survival environment.National sustainable development as national policy, environmental protection will be zui big subject of the 21st century.Air and water pollution should be controlled, it is necessary to strengthen management, and management is the basis of quantitative control of the pollution.

Our country is based on coal as main energy country, there are millions of chimneys discharge smoke into the atmosphere.Flue gas emission control is an important project of radical pollution, each stack must be install flue gas analysis instrument and meter, even Du emissions monitoring system.Flue gas flow quantity of kang hang it is very difficult, it's difficult to funnel large in size and shape is irregular, the uncertainty of the gas composition, velocity range is big, dirt, dust, corrosion, high temperature, no straight pipe and so on.

4, transportation

There are five ways: railway highway, aviation, water transport and pipeline transport.Application of pipeline transport is has already been done, but is not common.With environmental protection problem is outstanding, the characteristics of the pipeline transport has caught people's attention.Pipeline transport must be equipped with flow meter, it is the eye of the control, distribution, and scheduling, also is an essential tool for security supervisor and economic accounting.

5, and biotechnology

The 21st century will usher in the century of life science, is characterized by biotechnology industry will also get rapid development.A lot of material need to monitoring and measurement in biological technology, such as blood, urine, etc.The difficulty of the instrument development is great, wide variety.

6, scientific experiments

Scientific experiments need not only quantity of flowmeter, and variety is extremely complex.According to the statistics of flowmeter was in large part should be in more than 100 scientific research need, they are not batch production, sale in the market, many research institutions and large enterprises are set panel flowmeter in the development of the special.

7, Marine meteorology, rivers and lakes

These areas for open port, generally need to detect the velocity, and then calculate flow.Flow meter and flow meter is based on the physical principle and the basis of fluid mechanics is a common but instrument principle and structure and using conditions vary greatly.

Four, the main features:

1, the outer shock tube USES a single piece of material processing skills, no welding, high mechanical strength, high temperature resistant, corrosion resistant.

2, unique hexagonal structure, the unique shape of the distribution of a beam to ensure the stability of the low voltage signal, can produce high differential pressure signal, greatly improving the range ratio.

3, suitable for circular or rectangular pipe.

4, can provide online pull type or manual, automatic purging methods and devices, not achieve production maintenance.

5, average toba tube + 3 + + transmitter temperature pressure compensation valve group, composed of integrated structure, it is more convenient to use.

6, no flow coefficient, the long-term use cycle is long, stable and reliable signal.

7, small pressure loss of low energy consumption, energy saving effect is remarkable.

Five, the technical parameters:

1, the suitable diameter of 10 mm to 8000 mm;

2, the unique internal structure of quadratic mean, provides high accuracy (+ / - 1%) and high repeatability (+ / - 1%);

3, the accuracy is measured actual flow value plus or minus 1%;

4, flow range, typical of 10:1 (the differential value of 100:1);

Before 5, straight pipe required: normally after 7 d, 3 d to ensure measurement accuracy by 0.5% ~ 1.0%;

6, zui high working temperature is 500 ℃, zui high work pressure can reach 40 mpa;

7, the reference standard: ISO 3966-197, JB/T5325-1991 and GB/T2624-2006;

8, connection mode: insert flange connection, plug in threaded connections, pipeline flange, pipeline screw thread connection.

Main components:

1, according to the pipe diameter, with flange is installed on the pipe, made of stainless steel refined but become, according to the various parameters of the users with high precision wind tunnel laboratory simulation in tsinghua university, for supporting the characteristic curve of pipe and database, used for calculation.

2 is to display the measured results, flow totalizer.especially secondary instrument.Through wires connected to each transmitter and thermometer, the motherboard is equipped with advanced CPU and the application software, can use the display window and switch button to setup, calibration and the parameters display.

3, differential pressure transmitter will probe the differential pressure signal is converted into 4-20 madc analog current signal.

4, pressure transmitter in the gas flow measurement with pressure compensation.

5 in gas flow measurement, temperature transmitter temperature compensation.

6, dc power supply for pressure transmitter, differential pressure transmitter power and thermal resistance thermometer.

Seven, the operation and maintenance of pipe flow sensor:

The preparing work before put into operation:

1, sensors installed correctly:

Complete sensors installed in the line, must carefully check before put into operation, require welding is firm, in the right direction, not leak, strictly proper insertion depth, etc.

2, instrument calibration:

Sensor matching instrument differential pressure transmitter and intelligent flow integrating instrument (there could be pressure transmitter and temperature transmitter), etc.Must be after inspection and calibration, can be put into use.The instrument measuring range to conform to the requirements of the sensors and the measured medium.Such as measured zui large air flow Qmax = 5000 m3 / h, the calculation to calculate differential zui big value of sensor

Delta Pmax = 0.6 Kpa, the measuring range of differential pressure transmitter should be set-up of 0 ~ 0.6 Kpa, the corresponding output 4 ~ 20 madc current signal.For universal, flow totalizer.especially should according to the real-time flow range, differential pressure range, medium density, temperature, pressure, flow operation requirements, etc., prior programming configuration, input totalizer.especially can correct operation and make sure totalizer.especially display traffic.

3, instrument wiring correct:

Sensor and differential pressure transmitter, flow integrating instrument of measuring system, such as supporting the power cord, signal output to the input line between instrument, control and alarm, etc., in various instrument wiring board (also known as terminal board) are clearly marked, is must confirm and don't choose to use, before the operation of the instrument connection to check again and again.In order to do the preparing work before put into operation, in addition to read the instruction for use, you should also read the differential pressure transmitter operation instruction handbook ", "operation instruction handbook" intelligent flow totalizer.especially etc, comply with the instruction manual for the guidance of work.

Operation of work:

1, the measurement system is closed:

Operation of preparatory work has been completed, the medium to be measured with flow process piping, sensor measuring system is temporarily closed, then should make three balancing valve is fully open valve group, high pressure valve P l P2 and low pressure valve closed.Meter is in a state of power supply, preheating about 15 minutes.

2, open measurement systems:

Instrument after preheating, open measurement system.Open the Pl on three valve group and P2 valves, balance valve is still in the open.At this time, the differential pressure transmitter has filling the measured medium (gas or liquid), open the drain valve on the transmitter, quickly closed after discharge dirty liquid or gas.Then close three the balance valve on the valve group, transmitter that is entered into a state of differential pressure measurement.Output and the corresponding signal current differential delta P I delta P from the signal current value (m A) to calculate the pressure delta P values (KP) A.Also flow totalizer.especially into work state, show the measured medium flow.

If the above work all goes well, the flow meter works well, commissioning work is complete, delivery production use.

Eight, form a complete set of scheme selection:

1, is according to the measured medium, and the user use the pipe inner diameter, working temperature, working pressure and flow design and production.

2, ZW - 3051/1151 dp series differential pressure transmitter or other types of differential pressure transmitter

3, ZW - 308 series pressure transmitter, or other type of pressure transmitter

4, temperature transmitter, or other type of temperature transmitter

5, ZW - XMJA series or other types of flow totalizer.especially flow integrating instrument

6, of this intelligent velocity-equalizing tube flowmeter, pressure compensation can take temperature, and can show the instantaneous flow and cumulative flow medium medium temperature, the pipe, the pipe pressure and differential pressure equivalent, equipped with communication interface and 4 ~ 20 ma output.

Nine, equipment complete set:

1, velocity-equalizing tube flow sensor 1;

1 2, velocity-equalizing tube flow sensor operating instructions;

3, 1 certificate;

4, form a complete set of transmitter instrument and manual and certificate of approval (which can be ordered by the users themselves).

Ten, the blockage of pipe flow sensor design.

Toba pipe flow probe's unique design thoroughly get rid of the pig and past several average probe easily blocked, the characteristics of accuracy is not high, make a source of measurement accuracy, repeatability and reliability to a new height.

Just when switched on, the fluid in the pipeline under the action of static pressure, into the pipe bending, quickly formed a pressure balance state.When pressure balance formation fluid in high pressure pipe inlet, detour, no longer into the bend.

Toba pipe flow sensor of high, low pressure hole held in nature

In general, dust, sａnd and particles under the action of the vortex street force, concentrated in the very back of the probe.This is why the autumn leaves are always in the leeward behind the house.Probe flowmeter probe held in unique design, coupled with the nature of gravity whereabouts, prevents the particles into, this design essentially prevent the congestion and can create a very stable low voltage signal.

Work continuously probe flowmeter fundamentally eliminate the possibility of the wall, but in the following cases, still should pay attention to prevent:

1, when the pressure pipe leaking, probe high pressure balance to destruction of impurities in the diameter of the smaller particles are likely to enter the hole.

2, when the pipeline was shut down, because of the brown movement of molecules, small particles of impurities may enter the hole.

3, and frequent system key, formed in high, small particles of impurities may enter the hole, accumulate over a long period, it is possible to probe the jam.

4. Medium contains a large number of biological species, or containing fibrous material, may also cause the probe blockage.

Eleven, use requirements:

1, the current body shall be full of pipe flow and stability.

2, the fluid being measured should be single phase, the phase constant, for

Components of complex fluid must be similar to a single component of fluid can be used.

3, the current body under actual conditions of ReD should be greater than 3 x 104

4, should guarantee the sensor before and after the straight pipe length requirements.

5, pipe diameter greater than 100 ㎜ as well.

6, 2 d in front of the sensor on the surface of the pipe, should be clean and smooth.

12, product maintenance instructions:

Toba pipe flow sensor should be performed in the process piping overhaul regular cleaning, there are a number of ways for cleaning, such as air blow test tube accumulated filth;Scrub with kerosene and soft silk net, make each hole to maintain patency.May produce the cause of the failure and remove methods: serial number of failure causes clear way.

1, differential pressure signal output: high and low pressure valve is not open, open the high and low pressure valve.

2, high and low pressure balance valves did not tighten, tighten balance valve.

3, differential pressure signal output is too small, pressure system has a leak phenomenon;Seriously looking for, eliminate the leakage.

4, improper secondary table range selection: uninteresting facts limit pressure transmitter.

5, differential pressure signal output is too large, secondary table range matching is undeserved, augmenting the upper limit, differential pressure transmitter back-pressure aperture jams, cleaning velocity-equalizing tube, eliminate congestion.

13, selection of coding:

Model tag method: ZW - TBG - DN/toba pipe flow sensor
DN - - (㎜) such as DN500 nominal diameter of 500 ㎜ nominal diameter.

14, design selection and order notes:

1, the name of the measured medium;

2, the biggest, commonly used, flow range (m3 / h);

3, work pressure (Mpa), temperature (℃), the maximum pressure (Mpa), upper and lower temperature (℃);

4, medium density, viscosity,

5, pipe material, inner diameter, outside diameter;

6, the pipe laying and local resistance.

7, you need to display instrument of the measurement and control of form a complete set, please refer to the corresponding specifications, choose the right model or the information provided by our company technical personnel according to your designs for you selection.

8, if you have special want to, please contact our sales department.

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.