I. Product Overview:

LXZ series double rotor flowmeter (hereinafter referred to as flowmeter) is the ideal generation of positive displacement flowmeter in China. It is a new type positive displacement flowmeter designed and assembled by precision machining. A pair of spiral rotors is a moving body in the metering cavity, which plays the role of dividing, measuring, transporting and excreting the measured liquid. This type of flowmeter has a positioning gear added to the structure, so that the two rotors do not touch each other when rotating. The flowmeter has stable operation, low noise, less wear, high accuracy, strong viscosity adaptability, and can allow fine particles in the measured liquid to pass through, so that it is not easy to stick the meter. The meter is processed by electroless nickel plating, so it has the characteristics of corrosion resistance and wear resistance, and can replace the meter of stainless steel.

Two, the structure principle:

1. Principle:

The measurement of fluid flow with the LXZ series dual rotor flowmeter is completed in the metering chamber. A pair of helical rotors rotate under liquid pressure, and the enclosed space formed between the rotors and the wall of the measuring chamber (shaded part in the figure) drains 8 times the shadow volume per rotation. Therefore, according to this relationship, as long as the number of rotations of the rotor is measured, the cumulative flow can be calculated, and the instantaneous flow can be measured according to the number of rotations per second.

2. Structure:

The double rotor is mainly composed of shell, a pair of spiral rotor, magnetic coupling, reduction mechanism, adjusting gear, counter and signaling device. Flowmeter body is divided into monomer and double body two kinds. The monomer is the shell and the flowmeter box as one; The double body means that the shell and the flowmeter are two bodies. The rotational speed of the helical rotor is transmitted to the head counter by a magnetic coupling and a series of gear reduction mechanisms. Magnetic coupling is mainly composed of active magnetic steel and driven magnetic steel. Magnetic coupling can improve the working pressure and temperature of the flowmeter, safe operation, easy maintenance.

Three, application:

LXZ series double rotor flowmeter is a precision instrument for measuring and controlling liquid flow in pipelines. Widely used in petroleum, chemical industry, metallurgy, electric power, transportation, ship, oil depot, wharf, tank car and other departments, especially suitable for crude oil, refined oil, light hydrocarbons and other industrial liquid metering flowmeter can be indicated on the spot, word code direct reading and can be equipped with a signal, output electrical pulse signal, far to the secondary instrument or computer, composed of automatic control, automatic detection and data processing system.

Four, the main characteristics:

1, high accuracy, good repeatability, running balance, no pulsation and long life;

2, no straight pipe section before and after the flow meter, small installation space;

3, flow accuracy is not affected by pressure and flow changes, stable performance;

4, with temperature, pressure sensor, temperature and pressure compensation of gas;

5, with pulse signal, analog signal, through RS485 communication interface to achieve the centralized and real-time management of computer data;

6, low power consumption, available internal battery power supply, can also be connected to the external power supply;

7, high resolution special LCD screen, easy to read intuitive.

V. Technical parameters:

1, can measure liquid petroleum, petroleum products, chemical media, etc.;

2, nominal diameter (mm) 10, 15, 25, 40, 50, 80, 100, 150, 200, 250, 300;

3, accuracy (%) 0.1, 0.2, 0.5;

4, pressure loss 0.4-3 mPa.s <40KPa;

5. Working pressure (MPa) 1.6, 2.5, 4.0, 6.3;

6, temperature range (℃) -20 ~ +60, -20 ~ +120, +100 ~ +200, +150 ~ +250;

7. Protection level IP65;

8. Ambient temperature (-30 ~ +70℃);

9, medium viscosity (0.32 ~ 1000mPa.smPa.s);

Vi. Installation requirements:

1, environmental conditions: no corrosive fluid around, small mechanical vibration, less dust and away from heat sources. For intelligent flowmeters equipped with volume correctors, there should also be a regulated environment.

2, the ambient temperature: generally not more than -20 - +8O℃ range.

3, pipeline conditions: before installing the flow meter, the pipeline must be cleaned and purged to remove all debris, rust and dirt. The connecting pipe should generally be coaxial with the inlet and outlet of the meter, and no protruding object protruding from the pipe wall should protrude into the pipe. Flowmeters shall be installed stress-free, taking full account of piping stress due to operating temperature.

As a new positive displacement flowmeter, only to meet its working conditions and according to the requirements of correct use, in order to use its ideal cost-effective, prolong the service life. Therefore, the following three problems should be paid attention to in the selection and use.

1, because of the single shell structure, the highest pressure is not higher than 2.0MPa, so the high pressure long distance pipeline should not be used.

2. When used again in non-continuous use, the air in the metering chamber must be drained from the vent hole to prevent the increase of metering error and damage of graphite bearing due to cavitation.

3, the rotor clearance is not higher than 0.2μm, and the medium in the metering chamber stroke is longer, the purity of the metering medium is higher than other positive displacement flowmeters, need to use not less than 40 purpose stainless steel screen and regular cleaning. The rotor is made of cast iron, and the moisture content of the medium should not be higher than 5%, otherwise it will rust and affect the use.