Clamp-On Ultrasonic Flow Meters
Take control of your flow measurement with SmartMeasurement’s clamp-on ultrasonic meters—designed for accurate, reliable, and flexible performance across various industries and applications. Our clamp-on meters go on fast—no pipe cutting, no downtime. They use advanced Doppler and transit time tech to give you accurate flow readings without the mess. Whether you’re measuring water, chemicals, or any industrial fluid, you’ll get reliable results without the extra maintenance. Built for performance. Engineered for simplicity. Ready to install.
Trust SmartMeasurement for high-efficiency flow solutions that fit your process—not the other way around.
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Types of Clamp-On Ultrasonic Flow Meters
Clamps onto the outside of pipes to deliver non-invasive flow measurement. Designed for permanent installation, these meters track flow accurately without interrupting operations. Commonly used in water management, HVAC, and industrial processing.
A portable meter that provides accurate flow readings fast. It’s easy to install and perfect for temporary jobs like maintenance checks, flow verification, or system audits. Trusted in municipal water systems, HVAC, and industrial inspections.
Featured Products
Explore SmartMeasurement’s most popular clamp-on ultrasonic flow meters—engineered for precise, non-intrusive measurement in water treatment, HVAC, energy, and industrial systems. Easily compare models by installation type, application, or feature set to find the right fit for your project.
Not sure which model fits your system? Talk to an Engineer for expert guidance.
ALSONIC FX
- Size Range: 1"-48" (25-1200 mm) line sizes
- Temperature Range: -22~+230 °F ( -30 ~ +110˚C)
- Accuracy: 1-2% of reading
- Applications: Factory automation, HVAC, Building Automation
- Starting At: $1350
ALSONIC EG
- Size Range: Sizes 1-48" (25-1200 mm)
- Temperature Range: -22~+230 °F ( -30 ~ +110˚C)
- Accuracy: 1-2% of reading
- Applications: Residential/Industrial Building Automation, HVAC
- Starting At: $1450
ALSONIC DSP
- Size Range: ¾”-236" (20-6000 mm) line sizes
- Temperature Range: -22~+248 °F ( -30 ~ +120˚C)
- Accuracy: ±0.5 ~1% of reading
- Applications: Clean and dirty liquids; up to 30% total suspended solids
- Starting At: $4375
ALSONIC DDPL
- Size Range: 1"-120" (25-3000 mm) line sizes
- Temperature Range: -22~+302 °F ( -30 ~ +150˚C)
- Accuracy: 1.5%-3% of range
- Applications: Dirty liquids, Municipal & Industrial Wastewater
- Starting At: $3200
ALSONIC PL
- Size Range: 1"-48" (25-1200 mm) line sizes
- Temperature Range: -22~+230 °F ( -30 ~ +110˚C)
- Accuracy: 1-2% of reading
- Applications: Water, HVAC, MRO
- Starting At: $1950
ALSONIC MINI
- Size Range: ⅜”-1½” (10-40 mm) line sizes
- Temperature Range: 15~+300 °F ( -10 ~ +10˚C)
- Accuracy: 2% of range
- Applications: Chemical Injection, batching & dosing, Agriculture
- Starting At: $700
Alsonic DSPPL
- Size Range: ¾”-236" (20-6000 mm) line sizes
- Temperature Range: -22~+248 °F ( -30 ~ +120˚C)
- Accuracy: ±0.5 ~1% of reading
- Applications: Portable diagnostic tool for clean and dirty liquids; up to 30% total suspended solids
- Starting At: $6000
ALSONIC MN2 (ALsonic-MINI 2)
- Size Range: (Std) 3/8"~1 ½ " (DN10~DN40), (Opt) 1/4" (DN8)
- Temperature Range: (Std) -10°C~65°C (Non-frozen), (Opt) -10°C~105°C (Non-frozen)
- Accuracy: (Std) 3%FS, (Opt) 1.5%FS
- Applications: Food & Beverage, Automotive, Chemical processing, and dosing/mixing applications
- Starting At: $900
Need help choosing the right clamp-on meter?
Our engineers can match you with the best model based on your specs and budget.
Why Choose SmartMeasurement?
Clamp-on ultrasonic flow meters snap on fast, require zero downtime, and retrofit seamlessly with easy-to-mount sensors—no pipe cutting needed.
High Accuracy
Achieve precise readings with advanced ultrasonic technology, even in challenging conditions.
Cost Efficient
Consumes minimal power while delivering reliable performance.
Maintenance-Free
No moving parts design minimizes wear & tear, lowering maintenance costs.
Versatile Applications
Suitable for liquids and some gases, making them adaptable across industries.
Non-Invasive Measurement
Measure flow without disrupting the pipeline, reducing downtime and maintenance.
How Does a Clamp-On Ultrasonic Flow Meter Work?
A step-by-step look at how clamp-on meters deliver fast, accurate results — with zero downtime.
Step 1: Install the Sensors Externally
Clamp the ultrasonic transmitters and receivers securely onto the outside of the pipe without cutting, drilling, or interrupting flow. Quick and easy installation ensures fast setup with no system downtime.
Step 2: Send Ultrasonic Signals
The meter’s transmitters emit high-frequency ultrasonic signals through the pipe wall and the liquid inside in both the upstream and downstream direction.
Step 3: Measure the Signal Differential
The system measures the time it takes for the ultrasonic pulses to travel in each direction. The difference in signal time — the differential — is directly related to the speed of the flowing liquid.
Step 4: Calculate Flow Velocity and Volume
Using the measured velocity, the meter calculates the volumetric flow rate, providing accurate, real-time flow measurement without any disruption to the process.
Step 5: Output Data for Monitoring
The meter’s transmitter converts flow data into standard output signals (e.g., 4-20mA, pulse, Modbus) for easy integration with plant monitoring systems.
Applications of Ultrasonic Flow Meters
SmartMeasurement’s clamp-on ultrasonic flow meters are the go-to solution for accurate flow measurement across a wide range of liquid and gas applications without interrupting operations. Designed for versatility and precision, these meters easily mount to the exterior of pipes and allow for reliable velocity and flow monitoring without the need for cutting or process shutdowns. Key industries and uses include:
Water and Wastewater Management
Measure liquid flows in treatment plants, distribution networks, and irrigation systems with minimal maintenance.
HVAC Systems
Monitor chilled water, condenser water, and thermal energy systems efficiently with clamp-on transmitters and sensors.
Oil and Gas Industry
Track the flow of petroleum liquids, natural gas, and refined products without invasive pipe modifications.
Chemical Processing Plants
Control flow rates of aggressive or corrosive liquids where non-intrusive measurement ensures longer equipment life.
Energy and Power Generation
Optimize boiler feedwater systems, cooling circuits, and fuel delivery lines with precise, non-intrusive flow data.
With wide pipe size ranges as well as compatibility across different liquid and gas types, SmartMeasurement’s clamp-on ultrasonic meters are the preferred choice for flow measurement solutions.
SmartMeasurement Clamp-On Ultrasonic Flow Meters FAQ
Got questions about clamp-on ultrasonic flow meters? Here are some of the most common ones our engineers get — click to view the answers.
What is a clamp-on an ultrasonic flow meter?
A clamp-on ultrasonic flow meter is a non-invasive device that measures the flow of liquids by using ultrasonic signals transmitted through the wall of a pipe. Instead of being installed inside the flow stream, clamp-on sensors attach externally to the pipe, making installation quick and disruption-free. These meters are ideal for applications requiring minimal downtime, such as water treatment, HVAC, chemical processing, and energy systems.
How accurate is the clamp-on ultrasonic flow meter?
Clamp-on ultrasonic flow meters can achieve accuracy levels of ±1% to ±2% of reading under ideal conditions. Factors like proper sensor placement, pipe material, and flow profile influence measurement accuracy. For clean, full-pipe flow applications, especially with stable flow rates, clamp-on meters deliver precise and repeatable data—comparable to some in-line systems but with none of the installation complexity.
What is the difference between clamp-on and in-line ultrasonic flow meters?
The key difference is how the meter interacts with the pipe. Clamp-on ultrasonic flow meters mount externally and send signals through the pipe wall, while in-line ultrasonic meters are installed directly into the pipe and contact the fluid. Clamp-on meters offer easier installation, no system shutdowns, and reduced maintenance. In-line meters may offer slightly higher accuracy in challenging flow conditions but require pipe cutting and longer installation time.
What are the limitations of clamp-on ultrasonic flow meters?
Clamp-on meters are highly versatile, but they do have some limitations. Accuracy can decrease with highly aerated or slurry-filled fluids, or with poorly aligned sensors. They also depend on good acoustic coupling with the pipe surface, so heavily corroded or layered pipe materials may affect signal strength. However, these limitations are usually mitigated with proper model selection, installation, and calibration.