Steam Vortex Flowmeter

Description

1. Overview of Steam Vortex Flowmeter

The KNKE USA steam vortex flowmeter is specifically designed for the measurement of steam fluid in industrial pipelines, characterized by low pressure loss, high precision, and a wide range of measurement. This flowmeter is nearly unaffected by fluid density, pressure, temperature, or viscosity when measuring operating volume flow. With no moving mechanical parts, it offers high reliability and low maintenance requirements, ensuring excellent parameter stability. It utilizes a piezoelectric stress sensor, suitable for temperatures ranging from -20℃ to +250℃, and can output both analog and digital pulse signals, making it convenient for integration with computer-based digital systems, providing an ideal flow measurement solution.

2. Features of the Steam Vortex Flowmeter

1. Wide temperature range of measured media;
2. On-line maintenance possible under normal fluid conditions without stopping the flow;
3. Simple and robust structure, no mechanical wear, long service life;
4. High measurement accuracy, low pressure loss;
5. Easy installation, low maintenance requirements;
6. Capable of remote signal transmission, facilitating centralized monitoring and management.

3. Technical Parameters of Steam Vortex Flowmeter

1. Accuracy grade: 1.0 for liquid, 1.5 for gas (within standard flow range);
2. Repeatability: 0.2%, 0.3%;
3. Nominal diameter: DN50 to DN500;
4. Flow range:
   • Extended flow range: 20:1 for liquid, 15:1 for gas;
   • Standard flow range: 10:1 for liquid, 8:1 for gas;
5. Nominal pressure: 2.5 MPa;
6. Measured media temperature: -200℃ to +400℃;
7. Pressure loss coefficient: Cd≤2.4;
8. Power supply: 12~24V DC;
9. Output signal:
   • Voltage pulse: Low level ≤1V, High level ≥6V;
   • Standard current: 4~20mA DC;
10. Explosion protection grade: iaⅡT6.

4. Selection Parameters of Steam Vortex Flowmeter

1. Nominal diameter (mm): 15, 20, 25, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300 (insertion type for 300~1000);
2. Nominal pressure (MPa): DN15-DN200 is 4.0 MPa (higher pressure can be provided by agreement), DN250-DN300 is 1.6 MPa (higher pressure can be provided by agreement);
3. Media temperature (℃):
   • Piezoelectric type: -40 to 150℃, -40 to 260℃, -40 to 330℃;
   • Capacitive type: -40 to 400℃ (by agreement);
4. Material: 1Cr18Ni9Ti (other materials can be provided by agreement);
5. Allowable vibration acceleration:
   • Piezoelectric type: 0.2g
   • Capacitive type: 1.0 to 2.0g;
6. Accuracy: ±1%R, ±1.5%R; insertion type is ±2.5%R;
7. Flow range: 1:6 to 1:25;
8. Power supply voltage:
   • Sensor: DC +12V or DC +24V
   • Transmitter: DC +12V or DC +24V
   • Battery-powered type: 3.6V battery;
9. Output signal:
   • Pulse: High level ≥5V, Low level ≤1V;
   • Current: 4~20mA;
10. Pressure loss coefficient: conforms to JB/T9249 standard, Cd≤2.4;
11. Explosion protection grade:

• Intrinsically safe type: ExiaⅡCT2-T4
• Flameproof type: ExdⅡCT2-T5;

12. Protection grade: standard type IP65, submersible type IP68;
13. Environmental conditions: Temperature -20℃ to 55℃, relative humidity 5% to 90%, atmospheric pressure 86 to 106 kPa;
14. Suitable media: gas, liquid, steam;
15. Transmission distance:

• Three-wire pulse output type: ≤300m;
• Two-wire standard current output type (4~20mA): ≤1500m, load resistance ≤500Ω;
• RS485/HART: ≤1200m.

5. Installation Guidelines for Steam Vortex Flowmeter

1. It is not recommended to install the steam vortex flowmeter downstream of a regulating valve; it is preferred to install it upstream;
2. For normal installation, the upstream straight pipe section should be 20D, and the downstream straight pipe section should be 10D; if there is a regulating valve upstream, the flowmeter should be installed 50D downstream of the valve;
3. The straight pipe section at a reduced pipe and 90° elbow should be 20D;
4. For two 90° elbows, the straight pipe section should be 30D, and for spatial three-dimensional 90° elbows, it should be 40D;
5. Ensure that a single-phase fluid is being measured, as multiphase flow will affect accuracy;
6. If there are solid particles in the gas, a filter should be installed before the instrument;
7. When measuring steam or gas with humidity less than 95%, a moisture separator should be installed 50D upstream of the instrument;
8. If installed on a pipeline close to a wall, the distance between the pipeline and the wall should be no less than 0.5 meters;
9. The vortex flowmeter should not be installed in an insulated layer;
10. When installed on a vibrating pipeline, the pipeline should be supported or isolated with a flexible hose;
11. The direction of the fluid must match the direction of the arrow on the vortex flowmeter;
12. The gasket inner diameter must be greater than the inner diameter of the instrument during installation.