1、 Product Overview:
The LL series waist wheel flowmeter is a volumetric flow measurement instrument, with a measuring section made of stainless steel material and strong anti-corrosion performance. It can be used for flow measurement of corrosive crude oil or other corrosive media containing water. This flowmeter can display accumulated flow on site and is equipped with a remote output interface. It can also be equipped with a photoelectric converter to output electrical pulse signals or analog signals. It can be paired with a flow integrator for remote measurement, display, and control.
Its structural feature is that there is a measuring chamber inside the casing of the flowmeter, which has one or two pairs of waist wheels that can rotate tangent to each other. A pair of transmission gears are installed coaxially with two search wheels outside the flowmeter housing, which mesh with each other to allow the two waist wheels to be interlocked.
It can accumulate flow on site and is equipped with a remote output interface. It can also be equipped with a photoelectric converter to output pulse signals or analog signals, which can be matched with a flow integrator for remote measurement display and control.
The LL series waist wheel flowmeter mainly consists of three parts: a measuring chamber, a sealed coupling, and a counter. It can indicate cumulative flow and instantaneous flow on site, equipped with a transmitter and intelligent flow control instrument, and can achieve remote measurement and control. Widely used in petroleum, chemical, electric power, metallurgy, transportation, food processing, medicine, national defense, commercial trade and other departments for accurate measurement of fluids such as petroleum and petroleum products, chemical solutions, etc.
2、 Working principle:
The LL series waist wheel flowmeter forms a pressure difference at the inlet and outlet of the flowmeter when the measured liquid flows through the measuring chamber, and the waist wheel rotates under the push of this pressure difference. Simultaneously, by fixing a pair of driving gears on the waist wheel shaft, the two waist wheels are kept rotating continuously. As the waist wheel rotates, the liquid is continuously discharged from the flow meter through the measuring chamber. The amount of liquid flowing through each pair is four times the volume of the measuring chamber. Through a sealed coupling and a reduction mechanism, the number of rotations is reduced and transmitted to the counter, which indicates the instantaneous and cumulative flow rate of the liquid. Installing a transmitter in the counter mechanism becomes a waist wheel with a transmitter. Equipped with display instruments or microcomputer systems, it can achieve remote transmission (quantitative, cumulative, instantaneous and other functions) for automated measurement and control. Please refer to the classification manual for the display instrument for instructions.
3、 Applied Metrology:
LL type, can be used for flow metering of high viscosity liquids such as pure crude oil and heavy oil;
LL-D anti sand model can be used for flow metering of high viscosity fluids such as sand containing crude oil and heavy oil;
The LL-F stainless steel flowmeter is made of stainless steel material in contact with the medium, which has strong anti-corrosion performance and can be used for flow measurement of corrosive liquids, especially suitable for the chemical industry;
LY-C light oil type is particularly suitable for flow metering of low viscosity fluids such as light oil and diesel.
4、 Main features:
1. The measurement accuracy is high, and the basic error can generally reach plus or minus 0.2% to plus or minus 0.5%. When special requirements are met, it can reach plus or minus 0.1%. The characteristics of the flow meter are generally not affected by the flow state or the size of the Reynolds number.
2. Can be used for flow measurement of high viscosity liquids
3. The measurement range is relatively wide, with a typical flow range of 5:1 to 10:1
4. The word wheel counter accumulates the total amount of fluid without the need for external energy. It uses a instant noodle counter to display the cumulative flow rate, and one of them can be reset to zero, making it convenient for users to use in discontinuous metering situations.
5. There is no contact between measuring components, no wear, and a long service life.
6. The large diameter flowmeter adopts a rotor form to reduce the operating noise and vibration of the flowmeter.
5、 Technical parameters:
1. Basic allowable errors: ± 0.1%, ± 0.2%, ± 0.5%;
2. Nominal diameter DN (mm): 15-300;
3. Nominal pressure PN (M.Pa): cast iron (A), stainless steel (P) 1.0, 1.6, 2.5, 4.0, 6.3; Cast steel (E) 2.5, 4.0, 6.3, 9.6;
4. Temperature of the measured liquid:
a. Low temperature type: -40~+60 ℃;
b. Normal temperature type -10 ℃ to+80 ℃;
c. Medium temperature type -10 ℃ to+200 ℃;
d. High temperature type -10 ℃ to+300 ℃;
5. The viscosity of the measured liquid (mPa. s): 0.3~50000;
6. Pipeline connection: GB/T9118-2000 (Chinese standard flange); NIST (American Standard Flange); BSPT (British Standard Pipe Thread): NPT (American Push Pull Pipe Thread);
7. On site display: 99999999 L (cumulative flow) 9999999.9 L (single flow); 9999999.9 L (instantaneous flow rate);
8. Output signals: pulse signal, 4-20mA, 1-5V, 4-20mA+Hart protocol, MODBUS supports RS232 and RS485 communication (optional);
9. Explosion proof level: EXiaIIBT5EXiaIICT5 Protection level: IP65.
6、 Installation and use:
1. A filter should be installed before the flow meter, and the arrows on the two meter bodies should point in the same direction as the flow direction.
2. When the measured liquid contains gas, a gas separator should be installed before the flow meter.
3. Regardless of whether the pipeline is installed vertically or horizontally, the waist wheel shaft of the flow meter should be installed in a horizontal position (i.e. the dial should be perpendicular to the ground).
4. If it is difficult to see the reading clearly when the flowmeter is installed correctly, the counter can be rotated 180 degrees or 90 degrees.
5. The throttle valve should be installed at the inlet of the flow meter, and the opening and closing valve should be installed at the outlet. When using the opening and closing valve, it should be started slowly and not suddenly opened.
6. It is strictly prohibited to use sweeping steam through the flow meter.
7. In the continuous use department, a bypass pipeline needs to be added to the flow meter.
8. Before installing the flow meter, the pipeline needs to be flushed. During flushing, a straight pipe section (replacing the flow meter position) should be used to prevent welding slag, debris, etc. from entering the flow meter.
9. It is strictly prohibited to use water to calibrate flow meters made of cast iron and cast steel materials.
10. The flow rate of the flowmeter shall not exceed the technical requirements during use. The flow meter is optimal for normal operation at a high flow rate of 70-80%.
11. If the measured liquid has chemical corrosiveness, a stainless steel flow meter should be used. If the corrosiveness is strong, a flow meter made of 0Crl8Ni12MO2Ti material should be used.
English
