Integral orifice plate flow meter
The industrial steam as the secondary energy are very widely used. It has the very important economic meaning for the accurate measurement of the industrial steam, and also it is the main segment for commencing the energy-saving work. There are a big amount of measuring problems of the industrial stream in the lots of industries, such as oil, chemical , light industry, metallurgy, textile, food, and medicine etc.. Especially the country implement central heating policy, which require insistently to settle the problems of the accurate measuring of the large pipe and large flow of the industrial steam. For satisfying the needs of the industrial production, our company produce the LBJ series measuring equipments for the big diameter and big flow rate( thereinafter calling equipment), the applicable diameter specifications are Dg50，Dg80，Dg100,Dg150，Dg200，Dg250，Dg300，Dg350，Dg400，Dg450，Dg500，Dg600.
The measuring range of the equipments are wide, the reading accurately cooperate, which are the best flow measuring equipment in the domestic market. The equipments are mainly applied in the measuring of saturated vapor, overheating vapor, compressed air, and the mixed gas nonflammablely and nonexlosively. The equipments could be applied for the above mentioned flow measurement, display, meter and the online autocontrol of the producing process etc
The equipment make the most advantage of the classic the throttle element and smart flow meter with high accuracy, and through the design method, it adopts the actually operable adjustment method and electric technology to make the usability of the equipment owing the distinctive quality. Now the overviews are as followed:
1. The equipment tracks the magnitude change of the pipe flow rate, and increase the measuring accuracy largely.
2. The throttle element applied by the equipment is specially designed according o the international users supplying the technology conditions and make the reading more accurate and reasonable under the change scope of the scheduled pressure, temperature and flow rate.
3. The equipment adopts the hole plate angle connecting to the ring casing or flange to measure the pressure,
Thereinto, the applicable diameter of the flange for measuring the pressure is Dg450-600, with the features of high-temperature and high pressure resistance, and it is applicable to all kinds of calculations of large diameter and flow rate.
4. The equipment is easy to use, the reading is intuitive and no need to converse; And the equipment has strong complete set, and it is easy to maintenance, examine and manage.
5. For guaranteeing the measurement accuracy and being convenient for the users, the throttle elements has upstream and downstream measuring pipe and installation part.
6. The design of the equipment is rigorous, and the structure is reasonable, possessing the good performances of heat proof, moistureproof and shockproof to ensure the long term work stably.
1.The equipment model number
LBJ- the first character of Chinese Pinyin, symbolizes automatic compensation type flow equipment.
LBJ- x y z
X- symbolizes the specification of the pipe diameter.
Y-symbolizes the measured medium
Z-symbolizes the upper limit of the pressure range(the meter pressure)
x.y.z adopt the digit to symbolize the meanings as followed:
00 – Dg50 01 – Dg80 02 – Dg100
03 – Dg150 04 – Dg200 05– Dg250
06 – Dg300 07 – Dg350 08– Dg400
09 – Dg450 10 – Dg500 11 – Dg600
1-overheating stream 2. saturated stream 3-gas
00 – 0.4Pa 01 – 0.6Pa 02 – 0.8Pa
03 – 1.0Pa 04 – 1.3Pa 05 – 1.6Pa
06 – 2.0Pa 07 – 2.5Pa 08 – 3.0Pa
09 – 4.0Pa 10 – 6.0Pa 11 – 8.0Pa
12 – 10.0Pa
For example: the LBJ-124 type is one saturated stream equipment with Dg80 and the 1.3Mpa pressure upper limit.
2. The measurement range
a. the measuring range of the flow rate.
0 -100000(M3/h) compressed steam(working condition)
b. the measuring range of the pressure
0-10(Mpa) vopor hot water
0-2(MPa) compressed air
c, the measuring range of the temperature
0 ℃- 370℃hot water
100℃- 370℃saturated steam
100℃- 600℃overheating steam
0 - 90℃ compressed air
3.the pipe diameter
It is discussed separately for other pipe diameter users.
4.The measuring accuracy
a.the surrounding temperature is 0-45℃
b. the relative humidity of the air is not above 85%.
c. the working shake frequency is not above 25Hz, and the swing is not above 0.1mm(complete swing)
d. it should not have the corrosive gas in the surrounding air.
6.The time affect of the electrical applicance control ≤15ms
7.the electric power source
220 -50Hz Permitting change of the voltage
8.Circuit signal of the output flow
0-10mA，4-20mA,DC With the load ability 0-1500Ω constant flow property.
9. the circuit signal of the output pressure
With the load ability 0-1500Ω constant flow property. 0-10mA，4-20mA,DC extension need to be added the socket connector.
10. consumed power: ≤ 30 VA
When the fluid flows through the throttle element, the differential pressure is produced at the upstream and downstream sides. If the geosim and kinematic similarityof the unnominal throttle equipment is same as the nominal throttle equipment after completely tested, at the known conditions of the relative parameter, there is the definite value relationship between the static pressure difference and the fluid flow rate flowing. The practical formula of calculating the flow rate when the fluid flows the throttle equipment.
qm = 0.01251.α.ε.d2 20 (kg/h) (1) qv = qm/p
In the formula: qm the mass flux kg/h
qv the resistance value under the condition state.; αthe resistance value under the working state.;ε the swell factor when the fluid passes the throttle equipment; p the fluid density:kg/m3;
The differential pressure mmH2O
D20 the ringent diameter of the throttle element
When The differential pressure, pressure P examined by the sensing part is assembled by the primary instrument, and is changed into the relevant electrical signal by the differential pressure transmitter and the pressure transmitter, at the same time output the platinic thermal resistance Pt to the secondary instrument, and then the relevant flow rate qm is calculated out by the secondary instrument.
The matters need attentions before the equipment put into operation.
1. the connecting pipe system are injected with cold water as the transmission medium.
Measuring the high temperature vapor generally transmit the pressure through the cold water. Under the condition that the vapor does not be delivered in the pipeline, open the primary valve, pressure valve and balance valve, close the wash water valve, directly inject the cold water to the drainer by the tender filling hole, until the drainer is full. Of course, it also could close the balance valve and pressure valve, open the primary valve to import high temperature vapor which slowly condense to the water. Due to the too high temperature vapor which could easily damage the instrument, generally it is not adopted. Especially pay attention when measuring the high temperature vapor, the instrument is strictly forbidden to put into work when the connecting pipe is injected fully with water or the temperature is very high. To measure compressed air, cold water directly adopts the measured medium to transmit the pressure.
2. adjust the null drift of the pressure transmitters
Due to the water column in the connecting pipe produce an additional pressure, making the displayer have the additional reading. This additional pressure need to adjust to the zero, calling null drift. The specific practice is: close the primary valve, open the pressure valve, connect the power, open the shell of the pressure transmitter, adjust the migratory screw to make the output of the pressure displayer is zero.
3.The exhaust and liquor drainage of the differential pressure transmitter
After the connecting pipe is injected with water, sometimes it will gather less gas in the pressure-volume house of the differential pressure transmitter which will effect the pressure transmission, so that it must be overcome. Riving exhaust screw at the top of the positive and negative pressure-volume houses, it means the exhaust is complete when seeing the water squirting, then screwing down. When measuring the gas, it need to rive the screws at the below of the positive and negative pressure-volume house to liquor drainage. Generally the equipment put into new operation does not need to liquor drainage.
Examine the connecting pipeline system if there is any leakiness, close all valves and prepare to put into operation.
The operation step when the equipment put into use.
The most important matter needing to pay attention when putting into operation is that it could operate after the connecting pipe injects with water fully or the injected high temperature vapor become cooling. At this time, if only opening the pressure valve and the balance valve.
Installation and maintenance
1.The matters need to pay attention when installing the equipment
LBJ series differential pressure flowemeter is unitized supply. The main primary and secondary instruments and installation is finished by the making factory. The throttle element and the measuring pipe section also are also composed to the assembly by the making factory. Due to the transportation reason, all the usual materials for the installation are prepared by the users. The on-site installation , generally complete by the users according to the ordering contract and the ordering inquiry.
The on-site installation, according to the pipe arrangement and the practical situation of the spot indicated on the ordering inquiry carry out. the instrument cabinet on the site should be placed near the throttle equipment, the installation place should be convenient to check the instrument and maintenance, The instrument cabinet standing must be steady, with good shock proof. For protecting the electrical instrument, the instrument cabinet should be placed in the surrounding without strong heat emission, humidity, dust, strong shock and strong magnetic field interference.
2. The maintenance of the equipment
When the equipment put into operate, please keep the maintenance and timely examination, when finding the abnormal phenomenon, it should be deal with promptly.
1).please pay attention to check if the pipe has leakage. In case finding the leakage, it need to screw the screw cap of the active connector, and it need to change the gasket if it is necessary.
2). in 1-2 months, it need pollution discharge for the pipe generally. When discharging the pollution, what only need is to close the balance valve and open the valve of the pollution discharge. Closing the valve of the pollution discharge after the discharge medium is cleaning ,and reopening the balance valve after the temperature of the connecting pipe reduce to the normal..
3.)Every element of the instrument is adjusted specialized before out of the factory, and the user mustn’t carry out the normal adjustment
freely. Or it would damage the design intention of the equipment completely. If the users require to handle the adjustment principle of the equipment completely, please contact with us and check the adjustment data of the theoretical calculation, and grasp the adjustment method. And the users never are permitted to do something as their wishes, the result will be responsible by the users, and our company could offer the consultant services.