I. Overview

The LFX rotary steam flow meter is an instrument designed to measure the cumulative mass flow of steam, featuring a mechanical structural design. It displays readings locally via an indicator dial (mechanical) or an LCD screen, showing the mass of steam that has passed through the meter. It can also output pulse signals and includes manual pressure compensation or automatic temperature compensation functions. Due to its simple structure, moderate price, and wide measurement range, it is suitable for applications requiring steam flow measurement in industries such as petroleum, chemical, textile, and heating, as well as for flow metering in the cleaning industry.

II. Working Principle

    When the measured steam flows through the flow meter body, it is throttled by an orifice plate. Under the action of the pressure difference before and after the orifice, a portion of the steam enters the shunt pipe through a nozzle, forming a jet that drives the impeller at the upper end of the rotor shaft to rotate. The lower end of the rotor shaft is equipped with two damping blades that rotate in a damping chamber filled with damping fluid, providing damping motion. This allows the impeller to absorb the kinetic energy of the jet. When the rotational torque of the impeller balances with the damping torque, the rotational speed of the impeller is proportional to the mass flow of the measured steam passing through the flow meter. After calibration and scaling, the actual cumulative steam flow is reflected on the indicator dial. The steam flow meter mainly consists of three major components: the throttling body, the damper, and the indicator. It operates on the differential pressure-shunt principle. When the measured medium (steam) enters the throttling body of the flow meter, a portion flows through the main pipeline's throttling orifice plate, while another portion flows through the shunt pipe and nozzle, forming a jet that acts on the impeller, generating torque. This causes the impeller to drive the rotor shaft to rotate. Damping blades are installed at the lower part of the rotor shaft in a damping chamber filled with damping fluid, restricting the impeller's rotation. As a result, the rotational speed is much slower than the steam jet velocity, allowing the impeller to absorb the kinetic energy of the steam jet. The rotational speed of the impeller corresponds to the torque generated by the steam and the damping torque, establishing a quantitative relationship where the impeller speed is proportional to the flow rate.

III. Main Parameters and Performance Indicators

1. Measured Medium   Saturated steam, slightly superheated steam

(Degree of superheat ≤20°C)

2. Nominal Diameter       02;  05;  08;  10;

3. Operating Temperature   183°C (02)  

240°C (05; 08; 10);

4. Ambient Temperature       Required 0°C to 55°C

(Other temperatures available upon order)

5. Operating Pressure Range  0.03-1.0 (02)  

0.05-1.6 (05; 08; 10);

6. Installation Method        Horizontal installation

7. Density Compensation Method    Mechanical type with manual pressure compensation;

For details, please consult a sales engineer