Clamp-on type flow sensor for liquids

Measure liquid flow without contact using the PFUW clamp-on ultrasonic sensor

Discover PFUW, the clamp-on ultrasonic flow sensor for liquids. Measure flow without contact, avoid leaks and pressure loss, and monitor water, oil, chemicals and more with one device.

Measure liquid flow accurately without compromising your process

In modern manufacturing, controlling liquid flow is essential to ensure product quality, process stability and operational efficiency. However, traditional in-line flow sensors often create limitations that impact performance, maintenance and flexibility.
When sensors are in contact with fluid, they can introduce risks, increase costs and reduce reliability, especially when working with different or aggressive liquids.

Common challenges engineers face:

• Risk of leakage, clogging or contamination due to invasive sensors
• Limited compatibility: different sensors required for water, oil or chemical liquids
• Pressure loss affecting process efficiency
• Complex installation requiring pipe modification and machine downtime
• Inability to measure low flow rates accurately.

These limitations make it harder to optimise processes and adapt production systems.

PFUW series – Clamp-on ultrasonic flow sensor, non-invasive monitoring

The PFUW series is a clamp-on ultrasonic flow sensor designed to measure the flow rate of liquids from outside the pipe, without coming into contact with the fluid. 
This approach transforms how flow monitoring is implemented making it simpler, safer and more versatile.

Key benefits:

• Measure liquid flow without contact
  Non-invasive ultrasonic technology measures from outside the pipe, eliminating pressure loss, leakage, clogging and contamination, with no pipe modification required
• Use one sensor for multiple liquids
  Monitor water, oil, chemical liquids, antifreeze, beverages and hot fluids up to 90°C, increasing flexibility across different machines and processes
• Install easily on existing piping
  The clamp-on mounting only requires two/four screws, enabling fast retrofit, reduced downtime and simpler installation than traditional clamp-on flow sensors
• Monitor accurately from low flow rates
  Reliable measurement starting from 0 l/min, ideal for cooling circuits, process fluids and industrial utility lines
• Access real-time data and simplify integration
  Integrated display and IO-Link communication provide real-time flow monitoring, easy configuration and faster diagnostics
• User-friendly display
  A 128x128 dot-matrix LCD with dual-screen view displays multiple parameters at once for more information at a glance, while 90° rotation ensures clear visibility and easy visual checks from any installation angle.

See how clamp-on ultrasonic flow measurement works

Unlike conventional sensors, PFUW uses ultrasonic wave transit time technology to calculate flow rate through the pipe wall.

This enables reliable measurement without interrupting the process or altering the piping.

Talk to an SMC expert about your flow measurement application

Whether you need to monitor cooling fluids, chemicals or process liquids, SMC experts can help you select the right solution.

Improve your process reliability with non-invasive ultrasonic flow measurement.