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『Keyence Flow Meter Clamp On: External Transit-Time Fluid Velocity Monitoring』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
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Keyence Flow Meter Clamp On: External Transit-Time Fluid Velocity Monitoring
Quick Answer: Clamp-on transit-time flow meters from Keyence measure fluid velocity by sending ultrasonic signals through the pipe wall. They work best on clean liquids without bubbles or solids. Silver Automation Instruments offers an alternative clamp-on meter that covers pipe sizes from DN15 to DN6000 and costs a fraction of the Keyence price while delivering the same 4-20 mA HART and Modbus outputs.
How an External Transit-Time Clamp-On Meter Works
The meter clamps onto the outside of an existing pipe. Two ultrasonic transducers are mounted a set distance apart. One sends a signal downstream, the other upstream. The difference in travel time gives you the fluid velocity directly. No pipe cutting, no process shutdown. This is standard for both Keyence and Silver Instruments clamp-on models. For clean water, chemicals, or oils below 10 000 cP viscosity, accuracy reaches plus minus 1 percent of rate. You can log data locally or send 4-20 mA and RS485 signals to a PLC. The transducer gap depends on pipe material, wall thickness, and fluid sound speed. Most engineers use the built-in wizard, enter pipe DN and material, and the meter calculates the spacing automatically.
Keyence FD-Q versus Silver Instruments GXF-S: What Engineers Should Know
Keyence promotes the FD-Q series for small pipes from DN15 to DN200. The meter controls liquid flow and can switch a valve when flow deviates. It has a bright display and easy push-button setup. The full kit with sensor and controller can cost over USD 2 500. That fits Japanese OEMs and automated machinery builders. But for a process plant in the Middle East or a desalination plant in Australia, you may need to monitor a DN500 brine line or a DN800 cooling water header. Keyence does not go that large.
Silver Instruments GXF-S clamp-on meter works from DN15 all the way up to DN6000. We use the same transit-time principle and pair-matched transducers for accuracy. The transmitter supports Modbus RTU, 4-20 mA HART, and pulse output. The housing is IP66 rated, so it works in the Gulf heat and Southeast Asia humidity. Last month a chemical plant in Saudi Arabia ordered four units for DN200 and DN250 carbon steel pipes carrying 90 degrees C thermal oil. They replaced inline turbine meters and avoided welding. Total cost per loop was under USD 1 100. That is a real project number you can verify.
Fluid Conditions That Work and Those That Fail
Transit-time meters need a clean liquid. Suspended solids above 10 000 ppm or gas bubbles larger than 1 percent void fraction will kill the signal. In practice, we have seen a paint factory in Vietnam try a clamp-on meter on a 500 cP resin line with small pigment particles. The reading jumped around. The engineer switched to a Silver Instruments oval gear meter with PTFE gears and the output stabilized. For dirty fluids, a Doppler type ultrasonic meter sometimes works, but its accuracy is lower. If your flu
Installation Tips for Real Field Conditions
Pipe surface must be clean. Rust, paint layers thicker than 0.5 mm, and air gaps under the transducer give you a weak signal. Use the supplied coupling gel or a long-term bonding pad. On vertical pipes always mount the sensors on the side to avoid air collection at the top. For horizontal pipes, the 3 o clock or 9 o clock position is best. We have seen many customer photos with transducers at 12 o clock on a partly filled pipe. That always fails. Also, if the pipe is lined with cement or rubber, measure the exact liner thickness and enter it into the meter. Our GXF-S accepts a liner database for common materials like PTFE, glass, and cement mortar. Keyence FD-Q expects a bare metal pipe typically.
Cost and Lead Time: A Direct Comparison
A Keyence FD-Q20 clamp-on sensor with control module costs around USD 2 500 ex works Japan, with a lead time of 2 to 4 weeks. Silver Instruments GXF-S for a DN50 pipe, including the transmitter and paired transducers, is priced under USD 850 FOB Nanjing. We keep standard models in stock and ship within 5 working days. For bigger sizes up to DN6000, we build to order and deliver in 3 weeks. Because we focus on process industry and water utilities, our electronics accept two RTD inputs for energy metering. That lets you calculate heat flow in chilled water or hot oil loops. Keyence does not offer this thermal energy function. So if your project needs a clamp-on BTU meter, Silver Instruments has the integrated solution.
FAQ
Can a clamp-on meter measure gas flow? No, transit-time ultrasonic technology requires liquid coupling. For gases you need a thermal mass or Coriolis meter. Contact us with your gas type and pressure.
What pipe materials are supported? Carbon steel, stainless steel, copper, PVC, HDPE, and ductile iron. Always confirm wall thickness. Silver Instruments GXF-S includes a thickness gauge function.
Do we need to recalibrate after installation? The zero point is set at the factory. On site you can run an on-site verification if the pipe is full and flow is zero. No annual recalibration is mandatory, but we recommend a dry-block check every two years for ISO 9001 records.
Is the Keyence FD-Q suitable for a desalination plant? It works only up to DN200. Most desalination brine lines are DN300 to DN600. Silver Instruments GXF-S fits those sizes and handles 70 000 ppm saltwater without metal parts in contact with fluid.
How do we order the right sensor? Send us your pipe size (DN), fluid type, temperature (°C), and flow range to [email protected]. We will select the correct transducer and transmitter. Call +86-25-68650347 or WhatsApp +86-25-52155837 for a quick quote.
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