The XRATE Liquid On- and Offloading meter from Xsens provides accurate, reliable and cost effective flow measurement for any liquid. The meter is clamped to the outside of a pipe and measures liquids with ultrasonic signals straight through the pipe wall. It measures the transit time of acoustic signals through the liquid over the full bore of the pipe, measuring the full velocity profile to achieve high accuracy of 1% of flow. It typically provides an output in m3/hr or any other metric that clients require.

The clamp on design allows for easy installation (2-3hrs) and it can be installed close to bends and valves if needed. Since the meter is not in contact with the liquids, it is not affected by erosion, corrosion, waxing, scaling or leakages. This makes the meter very reliable and robust, with minimal maintenance required.

This meter is used to measure oil flow rates in tough onshore and offshore environments. It has a lightweight design and is available from 1.5inch to 30inch as standard and bigger on request. It comes with an integrated flow computer to provide the required outputs through analogue 4-20ma or digital Modbus signals.
There is no limit on pressure, viscosity, density or sour service as it does not affect the measurement or the meter itself. Turn down ratio is 1:400 meaning we can measure 0,1 to 40 m/s. There is also no need for static mixers or flow straighteners as the meter measures the full velocity profile.

For remote installations we can offer WiFi, cellular and satellite signals while adding solar panels for power. The meter can be accessed remotely through internet connection to be monitored and updated if needed.
Local displays for local reading of measurements can be added on request.

The meter is Ex Zone 1 and 2 certified for hazardous areas and can also be supplied without such certification to reduce cost.

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  • Measure liquid flowrates from outside of a pipe
  • High accuracy 2% of flow (including presence of gas)
  • Handles oil flow rates including free gas (up to 20%)
  • No limitation on density, viscosity, pressure or sour service
  • The meter can correct for uneven flow distribution by measuring the full velocity profile through patented helical shaped transducers
  • Rugged design for tough weather conditions and marine conditions
  • Can be installed close to bends, valves and other restrictions
  • Clamp on design means easy installation in 2-3 hrs
  • Very suitable for large pipe diameters (standard up to 30”, larger on request)


Xsens Specification

Item Requirement Range
General 1 Line size 1.5″ to 30″ and higher
2 Line Schedule Any
3 Pipe Class Any
4 Pipe Material Carbon Steel, SS316,Duplex (others)
5 Hazardous Area Protection Atex, IECEx Zone 1 and 2
6 Ingress Protection IP 66 (higher on request)
Process Conditions 7 Fluid Hydrocarbon / Water / Liquid mixture
8 Phase Liquid with or without gas (typically up to 20% GVF)
9 Corrosive / Erosive Can handle both due to clamp-on design
10 Case Min Max
11 Flowrate m/s 0.1 40
12 Density No limit No limit
13 Design pressure No limit No limit
14 Design Temperature -20 deg C 100 deg C (higher as option)
15 Viscosity Range from water to heavy bunker oil
Sensor 16 Sensor Type Ultrasonic non-intrusive (clamp-on type).
Up to six pairs (redundancy)
17 Measurement Principle Ultrasonic Guided Wave Transit Time & Time Of Flight and Doppler
18 Housing Sensor Material SS316 / Aluminium
19 Cable from sensor to transmitter Armored, flame retardant type
20 Uncertainty  +/- 2% of flow at 0 gas and +/-5% up to 10% GVF (add +/-0,01 m/s)
21 Turndown ratio 400:1
22 Removable Assembly Yes
23 Electrical Connection 4-20mA / Modbus (WiFi, Canbus, Profibus and other on request)
24 Upstream Straight Length 2-5D (target)
25 Downstream Straight Length 2-5D (target)
26 Flow Straighteners Not required
27 Static Mixer Not required
Transmitter 28 Housing Material SS316 / Aluminium
29 Calibration 0 – 100%
30 Electrical Connection To custom specifications
31 Power Supply 12-24 VDC (external power, or other).
Typical 9,5Watt, 11 watt at start up
32 Output Signal Modbus serial connected to flow computer via RS-485 /4-20mA
(others on request)
33 Mounting Integrated in sensor
Options 34 Pressure Transmitter NA
35 Temperature Transmitter 2*PT 100  elements included
36 Flow Computer Included
37 Local Display Optional
38 Mounting Kit Included
39 Weight From 25 kg to150 kg depending on size
40 Dimensions See GA drawings from Xsens