Ultrasonic Flow Measurement on Large Mains Water Pipes
VALVES & FLOW CONTROL THE METRI PRO-LITE
ICENTA
Ultrasonic Flow Measurement on Large Mains Water Pipes
Portable ultrasonic flow metering offers a practical approach to non-invasive flow measurement , eliminating the need to cut into pipes . This makes them ideal for a variety of applications , particularly in situations where disrupting existing infrastructure is undesirable and they are very cost effective compared to other technologies when used on large pipelines . iCenta field tested the Metri Pro-Lite on a large diameter water transmission pipe , evaluating its performance and suitability for such applications .
Testing the Metri Pro-Lite on a 1260 mm Mains Water Pipe
The Metri Pro-used to measure the flow within a large diameter raw water transmission pipe . The reservoir was constructed in the 1980s and the pipe itself is made from Ductile iron and has a 10 mm cement liner . It is 1260 mm and was deemed to be in good condition . This test aimed to assess the suitability of the system , and gain insight into its performance using the standard sensors . Sensor Selection and Installation The Standard 1 MHz sensors , being a proven technology in production for several years , were the natural starting point . A small , medium and large sensor are available – the 1MHz sensor tested here would be considered to be the medium sized version .
Ultrasonic transit-time difference flow meters are pulse – echo systems where the two-way travel times of ultrasonic pulses are accurately measured . Typically , one pulse is sent at an angle to the flow ( from precise wedge-shaped transducers ) and a minute difference is measured between a pulse travelling upstream compared to a pulse travelling downstream – the ΔT time difference . These measurements resolve time differences to parts per billion and as electronics becomes more capable and at a more reasonable cost , these meters now offer outstanding value for money .
Setting the meter up is a simple procedure where you measure the pipe circumference , and enter the pipe material , fluid type , the fluid temperature , them number of acoustic traverses and any liner details . The Metri Pro-Lite has the option of using a dedicated wall thickness gauge . It has a useful A-Scan display and really is a welcome addition to the system .
Initially , the sensors were installed in a single path or “ Z mode ” on opposites sides of the pipe . This configuration ensures optimal signal strength . Installation involved careful alignment using a bubble level and a ratchet strap to secure the sensors in place . A good signal was immediately detected .
Evaluating “ V Mode ” Performance
This is a large pipe , and to further explore the capabilities of the Metri Pro-Lite , the Standard 1 MHz sensors were then tested but this time in a 2 path “ V mode .” configuration , where the sensors are on the same side of the pipe . This mode offers an alternative configuration for signal transmission and reception , and the advantage is that the ΔT time shift is doubled . While the signal strength was marginally lower in “ V mode ” compared to “ Z mode ,” it remained sufficiently strong for accurate flow measurement .
Key Takeaways from the Field Testing
The field testing successfully demonstrated the Metri Pro-Lite ’ s ability to measure flow accurately in large diameter ( 1260 mm ) water pipes containing water . The tests revealed the Standard 1 MHz ( IC- US-M10 ) sensors , although physically quite small , certainly “ pack a punch ” reliable results in both “ Z ” as well as the more challenging “ V ” mode . In terms of calibration , of course the water companies ’ data is confidential and as we logged the data , with its real time clock , we could look at the flowrates from the reference meter , and we were able to confirm a close agreement to the actual figure , within 2 % of reading .
Beyond the Data : User Experience and Additional Features
In conclusion , field testing the Metri Pro-Lite on a large diameter water pipe proved its capability for non-invasive flow measurement in this challenging scenario . The Standard 1 MHz sensors showed their capability on one or the larger pipes in the UK , offering reliable and a very cost-effective performance . The user-friendly design and comprehensive data logging features further enhance the value proposition of the Metri Pro-Lite , making it a compelling solution for a wide range of flow measurement needs . iCenta have over 20 years ’ experience within the ultrasonic flowmeter market which is continuously expanding . With experienced staff and a growing market , iCenta are well positioned to help with ultrasonic ( and all other technology ) flowmeters . Please bear in mind that ultrasonic flow meters are applicable to many process control environments and have matured into an accurate and cost-effective solution .
www . icenta . co . uk | sales @ icenta . co . uk | 01722 439880
114 PECM Issue 68