Industrial ultrasonic flowmeters are non-contact flow measurement instruments. They operate based on the principle that the speed of ultrasonic waves in a fluid varies with the flow velocity. By measuring the time difference of ultrasonic wave propagation in the downstream and upstream directions, the flow rate is calculated.

According to the contact method between the probe and the pipe, it is mainly divided into the following two types:

1. External clamp type (external installation)
   • Working principle: Two probes are fixed on the outer wall of the pipe with a clamp, without the need for drilling or cutting the pipe.
   Advantages:
   • Completely non-contact: No contact with the fluid, no pressure loss, and no interference with the fluid.
   • Easy installation: Can be installed without stopping production and is convenient for maintenance.
   • Wide application range: Almost applicable to all pipe materials (steel, cast iron, PVC, copper, etc.)
2. Insertion type (invasive type)
   • Working principle: Open a hole in the pipe and insert the probe directly into the pipe through a ball valve or other device, with the front end of the probe in contact with the fluid.
   • Bundled type: Fix the probe at a specific position on the outer wall of the pipe, and the acoustic wedge penetrates the pipe wall.
   • Flanged type: The probe is fixed on the pipe through a flange.
   • Pipe section type: Pre-install the probe on a standard pipe section to form an integral unit.
   Advantages:
   • High accuracy and good stability.
   • Not affected by pipe wall material and lining.
   • Suitable for large-diameter pipes and cost-effective.

• No moving parts: High reliability and low maintenance.
• Multi-functional measurement: Can measure forward/reverse flow, instantaneous/accumulated flow.
• No pressure loss: Save pumping costs, especially suitable for high-flow applications.
• Wide range ratio: Wide measurement range, adaptable to large flow rate variations.
• Applicable to multiple media: Can measure various uniform liquids such as water, seawater, wastewater, oil, and chemicals.
• Intelligent diagnosis: Advanced meters have self-diagnosis functions for signal quality and installation quality.

• Fluid characteristics: The type of medium (water, oil, gas, etc.), temperature, pressure, viscosity and whether it contains impurities must be clearly defined.
• Pipeline conditions: Pipe diameter, material, straight pipe section length (5D before and 10D after) and installation space affect measurement accuracy.
• Technical parameters: Accuracy (±0.5% to ±1%), repeatability, communication interface (such as Modbus, RS485) and explosion-proof certification.
• Environmental adaptability: Temperature resistance, corrosion resistance and anti-electromagnetic interference ability.

• Industrial field: Oil pipeline flow monitoring, chemical process control, power plant circulating water metering.
• Environmental protection and municipal: Wastewater treatment flow distribution, water supply network monitoring.

Summary: Industrial ultrasonic flowmeters are powerful tools. Their successful application relies on the trinity of "correct selection + professional installation + accurate parameter setting". Under suitable working conditions, they can provide long-term, reliable, and high-precision flow measurement solutions.