Far eastone oval gear flowmeter

ZW - LC seriesFar eastone oval gear flowmeterIs a kind of displacement measuring instrument, mainly by the measurement of shell, elliptical gear rotor and driving part.Used in the pipe fluid flow continuous or discontinuous measurement and control instrument.Oval gear flowmeter sensor and secondary instrument of oval gear flowmeter, it is a kind of measuring liquid flows through the pipe flow of the total displacement meter, has remote display the function of the instantaneous flow and cumulative flow, can be combined with most of the control system, realize the automation of traffic detection and control.

Second, the working principle:

ZW - LC series remote measurement part of the oval gear flowmeter is mainly composed of two mutually meshing elliptical gear and shell (measuring room), elliptical gear turn every week the parallelism of the measured medium quality for half moon volume 4 times, by the elliptical gear meteor millions of volume flow rate Q: Q = 4 n nu 0

Type:

N - the rotation of the elliptical gear frequency (r/s);

Nu 0 - half moon part volume (Mr.).

So, in the half moon volume of the oval gear flowmeter nu 0 given conditions, as long as the measure of elliptic gear rotational speed n, can know the measured medium flow.

Elliptic flow meter flow signals (that is, the elliptic gear rotating speed n) showed that has two kinds of on-site display and remote transmission.

In situ show that the gear rotation through a series of deceleration and adjust speed than institutions, directly connected to the instrument panel on the indicating needle, and the total amount after mechanical counter display.

Far eastone shows mainly through the reduction gear after * magnet rotates, making spring relay contact with * magnet synchronization to make or break the rotation of the same frequency, thus far to another display instrument issued by electrical impulses.

Applications:

ZW - LC series far eastone oval gear flow meter is used for measurement of pipeline fluid flow under certain pressure.It has a simple structure, reliable use and high accuracy, flow field has no special requirements for import and export of the pipe, the viscosity of the measured medium range and flow range is very wide, etc.Widely used in petroleum, chemical industry, medicine, transportation, food and other industrial and commercial sector of liquid flow detection.

1, ZW - LC - A cast iron type flowmeter, it is widely used in all kinds of oil products and for the measurement of the cast iron is not corrosive liquid medium;

2, ZW - LC - E cast steel type flowmeter, used in high pressure, low corrosive medium measurement;

3, ZW - LC - B stainless steel type flowmeter is widely used in strong corrosive liquid medium, such as acid, alkali, salt and the measurement of organic compounds, etc.

Four, the main features:

1, to adopt advanced technology of non-contact letters;

2, high precision, affected by the liquid viscosity changes little;

3, small resistance, is particularly suitable for small flow measurement;

4, intrinsically safe explosion-proof, explosion-proof marks ExiaIICT5;

5, 5 VDC input voltage current 24 ma associated equipment: security gate.

Five, the technical parameters:

1, allows basic error: plus or minus 0.1%, plus or minus 0.2%, plus or minus 0.5%;

2 DN, nominal size (mm) : 4 ~ 200;

3, nominal pressure PN (M.P a) : cast iron, stainless steel (P) (a) 1. 0, 1.6, 2.5, 4.0, 6.3;Cast steel (E) 2.5, 4.0, 6.3, 9.6;

4, the liquid temperature to be tested: low temperature type - 40 ~ + 60 ℃ and room temperature type - 10 ℃ ~ + 80 ℃

5, medium temperature type - 10 ℃ ~ + 200 ℃ high temperature type - 10 ℃ ~ + 300 ℃;

6 and measured liquid viscosity (mPa) s) : 0.3 ~ 50000;

7, pipe connection: GB/T9118-2000 standard flange (China);NIST (the standard flange);BSPT (British standard pipe thread) : NPT (American tapered pipe thread);

8, the scene show: L (traffic) 9999999.9 L (single flow) 9999999.9 L (instantaneous flow);

9, output signal, the pulse signal, 4 ~ 20 ma, 1-5 v, 4 ~ 20 ma + HART protocol, the MODBUS support RS232 and RS485 communication (optional);

10, explosion-proof level: EXiaIIBT5EXiaIICT5 protection grade: IP65.

Six, error calculation and adjustment:

1, the basic error of flowmeter, by the verification flow point of all measured values respectively press type calculation: (volume) E = Vm - 99% (V/V

E - meter error (generally refers to the cumulative error) take two significant figures.

The Vm - meter measured values (i.e., values)

V - were revised, flowmeter standard device measured value (that is, the actual value) from the basic formula of error, when the Vm > V, flowmeter fundamental error for "+" values, said flowmeter is going faster.

Vm < V, flowmeter basic error for "-", said flowmeter walked slowly.

2, in order to make the error of flowmeter, within the basic error limit is often the need for error.By changing in counter namely inside a pair of adjusting gear (tooth) are adjusted to change the mechanical transmission ratio, so that the flow meter's worth to adjust.

3, error adjustment can't change the flow characteristic of the flowmeter, the characteristic curve of artificially in a new coordinate system.

4, in general, in the rules (or actual use) flow within the scope of its basic flow check point error range is not big five, the regulation accuracy of basic error limits, all can be adjusted by the error flowmeter qualified basic error.

Flow meter has been used, usually with the adjustment of the original gear set first for error detection, and then according to the error of the specific situation to adjust error.

Seven, measurement requirements:

1, the flow measurement has nothing to do with the flow of the fluid, it is because the oval gear flowmeter is depend on the measured medium pressure head driving elliptical gear rotating and measure.

2, the greater the viscosity of the medium, from gear and measuring the less empty clearance leakage of the leak out, therefore the greater the nuclear medium sticky skin, the smaller the leakage error, to measure more advantage.

3, high measuring accuracy, suitable for high viscosity medium flow measurements, but not containing solid particles of fluid (solid particles will gear jammed, so that you can't measure traffic).If the mixed with gas in the liquid medium to be measured, can also cause measurement error.

Eight, installation and use:

1, the instrument should be in the direction of the installation direction arrow as shown on the instrument housing with the liquid in the same direction, installation position should be paid attention to facilitate reading.

2, instrument installation as far as possible in normal situation, do not install in place of harmful gases and strong heat radiation, the meter counter part.

3, elliptical gear installed into a horizontal position as much as possible, should immediately dial into vertical position (dividing "0" should be in the above, in order to reduce the elliptical gear friction between the two plane and shell, reduce the wear parts.

4, meter installed in the output of the pump, if installed in the suction side, instrument filter pressure loss suction negative pressure of pump, pump shaft of the liquid outflow also caused the instrument error increases, the pump suction flange should also prevent side leakage, otherwise can cause the error of the instrument.

5, need to install filters in front of the instrument, not to let more than 0.2 mm particles through, prevent blockage due to particles, filters should be easy to clean.

6, instrument before installation of valve, the pipeline fluid only one-way flow, prevent damage of counter.

7, instrument proposal as shown in figure 5, bypass and valve, can be installed in horizontal or vertical pavilion to the other direction, from top to bottom, from bottom to top, from left to right, from right to left.

8, instrument when use, should be in the table is full of liquid, liquid to be tested should not be mixed with the gas inside, otherwise the measurement is not allowed.The liquid mixed with gas separator must be installed in front of the instrument.

9, instrument before installation, the pipelines should be carefully before removing debris, only when the instrument connected to pipe, to remove the plug on the instrument interface, to prevent debris into the table.When installing a instrument, should prevent debris into the pipeline.

10, flow in excess of the prescribed flow, oval gear as RPM increases wear increases, and the pressure loss has increased dramatically, so should avoid to use, below the flow is still can calculate, but error increases, the liquid viscosity meter in 10 centipoise start traffic is about to about 1% of full scale.

11, each instrument in the factory were in 7 # mechanical oil at room temperature calibration, oil viscosity varies between room temperature and normal temperature 13 centipoise next month.Volumetric flowmeter measurement of liquid viscosity change in theory, will not affect the measuring precision, but actually because of measuring gap exists between the interior wall and the elliptical gear, clearance of the leak amount affected by liquid viscosity changes.

12, when used to measure high viscosity liquid, usually heat the liquid in order to reduce the viscosity, flow, and then the pipe after the instrument downtime, meter inside is full of liquid cooling and sticky.You must steam in the title is enabled, external washing liquid thermal heating method, after waiting for liquid viscosity reduced in the instrument to use, otherwise the mucus will live transmission parts such as the damage.Do not sweep line steam through the table body, so as not to damage the instrument.

13, measured liquid temperature should not be higher than the specified value, more than even stuck, liquid temperature changes viscosity influence also additional error.In addition, the increase of the temperature increase also caused new moon space volume, make the instrument "go slow", when measuring chamber with elliptic gear such as cast iron, additional error is about 0.33% + / 100 ℃;Measuring room for cast iron, the elliptical gear such as cast aluminum when additional error is 0.14% + / 100 ℃.

14, of the pipeline flow should not dramatically increase or decrease, avoid pipeline vibration, hydraulic shock and stress the phenomenon such as volatility, otherwise will affect the normal work of the instrument.

15, the pressure loss is directly proportional to the square of the liquid flow rate, liquid viscosity increases, the pressure loss is also increased.

Nine, note:

1, right after installation, in accordance with the requirements when using can ensure enough accuracy, usually the cumulative value of precision can reach 0.5, is a more accurate flow meters.

2, however, if the use of the measured medium flow rate is too small, the instrument will highlight the influence of the leakage error, can't guarantee enough accuracy of measurement.

3, therefore, different specifications have a permitted to use the traffic, only when the actual measured flow is greater than the lower limit value, the measurement precision can be guaranteed.

4, secondly, when using, pay attention to the temperature of the measured medium cannot be too high, otherwise not only can increase the measurement error, and there are may be stuck in the gear.

5, therefore, in the instrument by using temperature range.Use for a long time after the gear flow meter, the internal gear are corrosion and wear and tear, which affect measurement accuracy.

6, therefore, often should observe, and regularly check removed, if conditions permit calibration on a regular basis as far as possible.

Ten,The dimensions:

table1, the size of the standard shape: unit: mm

table2, cast steel, cast steel, high viscosity, high temperature cast steel standard dimension: unit: mm

Cast iron, cast steel, high temperature type standard dimension: DN15 ~ DN25, A and B size according to the above-mentioned data add 160 mm hot extension tube: DN40 ~ DN80, A and B size according to the size of the table with 300 mm hot extension tube, the rest of the size with the table size accordingly.
Table 3, stainless steel type standard dimension: unit: mm

Eleven, measuring range:
Ordinary cast iron type (AType), cast steel,EType), stainless steel,B）

Twelve, selection of coding:

13, design selection and order notes:

1, choose oval gear flow timing, it is suggested that according to the measured liquid flow control meter flow range of 30 ~ 70% choose specifications;According to the fluid temperature, and the size of the pipeline pressure, and corrosion properties of liquid viscosity, etc to select flowmeter types;

2, when ordering, please specify the model of flow meter, diameter (mm), whether to ask explosion-proof, name of the medium, flow range (m3 / h), work pressure (MPa), temperature (℃), medium viscosity (MPa) s), to measure the corrosion medium, the user must also specify the medium corrosion properties, medium concentration (%), medium temperature (℃);

3, this product can according to user requirements, within the header assembly electrical/current transmission device;

4, when ordering parts, please click and fill in the figure, the collapse of the list;

5, user, if you have special request, please put forward in order;

6, our company can provide filters, venting device with flow meter, intelligent flow integrating instrument.

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.