Common faults of ultrasonic flowmeter and their solutions

Project Overview

Ultrasonic flowmeters are widely used in flow measurement. Supmea Measurement and Control HSC series ultrasonic flowmeters have a heat accumulation function. They are equipped with a pair of platinum resistors and adopt the international standard enthalpy value heat calculation formula (enthalpy difference method). It can realize the measurement of cold/heat. In order to meet the on-site needs of users in different working conditions, this series of products is divided into integrated, split modular and battery-powered types. It is suitable for cold/heat measurement of air conditioners and unit buildings. Heat measurement in heat exchange stations and heating company pipe networks. It can be used in places where other types of flow meters cannot be applied, such as open channels or river projects. However, equipment will all fail. The following are common failures and solutions for ultrasonic flow meters:

1. Inaccurate readings and large errors

(1) Common reasons

1. Improper sensor location: The sensor is installed at the top and bottom of a horizontal pipe, which is susceptible to sediment interference; or it is installed on a pipe with downward water flow, and the pipe is not filled with fluid.

2. Pipeline vibration or flow pattern fluctuation: For example, the flow meter is installed downstream of the regulating valve, pump, orifice, or there are venturi tubes, orifice plates and other devices nearby.

3. The input pipe diameter does not match the pipe inner diameter.

4. The outer wall of the pipe is not clean or uneven.

(2) Treatment method

1. Optimize the installation position of the sensor: Install the sensor on both sides of the pipeline or on a pipe section filled with fluid to avoid vibration sources and flow fluctuation devices.

2. Adjust the coupling between the sensor and the pipeline: ensure that there is no interference in signal transmission, and use couplant or coupling parts if necessary.

3. Modify the pipe diameter: make it match the input pipe diameter of the flow meter.

4. Thoroughly clean the outer wall of the pipe: choose a flat pipe installation location and avoid installing on welds or uneven areas.

2. Sensor failure

(1) Common reasons

1. Bubbles or particles block the sensor: the ultrasonic signal cannot be transmitted correctly to the receiver.

2. Sensor damage: Signal loss caused by long-term use or mechanical damage.

(2) Treatment method

1. Regularly check the ultrasonic path of the sensor: make sure there are no bubbles or particles blocking it, and clean it in time.

2. Regularly maintain the sensor: Check for damaged or worn parts and replace the sensor if necessary.

3. Power supply and computer problems

(1) Common reasons

1. Unstable power supply voltage: causing the flow meter to work abnormally.

2. The battery is exhausted: If the flow meter is powered by batteries.

3. Computer failure: such as data loss, crash, etc.

(2) Treatment method

1. Ensure stable power supply voltage: Provide a stable power supply environment for the flow meter.

2. Check the battery power regularly: replace the battery in time to avoid running out of power.

3. Restart the computer: Solve the problem of data loss or crash caused by computer failure.

IV. Changes in fluid properties

(1) Common reasons

1. Temperature changes: affect the speed of sound, which in turn affects the accuracy of measurement.

2. Fluid density, viscosity and pressure changes: also affect the speed of sound, leading to unstable measurement.

(2) Processing method

1. Use the temperature compensation function: correct the measurement results according to temperature changes.

2. Ensure that changes in fluid properties do not exceed the specification range of the flow meter, and adjust measurement parameters if necessary.

5. External interference

(1) Common causes

1. Electromagnetic interference: such as electromagnetic interference generated by frequency converters, high-voltage cables, etc.

2. Noise interference: such as machine vibration, sound, etc.

(2) Treatment methods

1. Use shielded cables and electromagnetic shielding measures to reduce the impact of electromagnetic interference.

2. Install the flow meter in an area with less noise: or use sound insulation measures to reduce noise interference.

6. Other common problems

1. The probe alarms after being used for a period of time: Clean the probe regularly, once a year is recommended.

2. Liquid accumulation and freezing blockage in the pressure pipe: purge or energize the pressure pipe and heat it to solve the problem of liquid accumulation and freezing blockage.

Ultrasonic flowmeters may encounter various faults during use, but through reasonable installation, regular maintenance and troubleshooting, these problems can be effectively avoided and solved to ensure the stable operation and accuracy of the flowmeter. Measurement. For more questions related to instrumentation, you can consult Supmea Measurement and Control.