A chemical plant producing alcohols and industrial solvents needed continuous flow monitoring on transfer lines in an explosion-classified area, while avoiding direct contact with aggressive, high-purity fluids. Clamp-on YF-W200D meters were installed on the outside of the stainless pipework for a non-intrusive, shutdown-free solution.
The challenge
- Solvent vapors create a classified hazardous zone requiring Ex instrumentation.
- Aggressive, high-purity fluids make wetted sensors undesirable.
- Production could not be stopped to cut or tap the pipelines.
- Needed 4–20 mA flow signals into the DCS for transfer control.
The solution: YF-W200D
The plant mounted clamp-on transducers externally on stainless transfer lines and located the YF-W200D Ex converter on a nearby wall. The 4–20 mA output feeds the DCS and RS485 provides totalized volume for batch records. See the YF-W200D specifications →
- Non-contact clamp-on measurement protects fluid purity and resists corrosion.
- Installed with no shutdown, tapping or pipe modification.
- Dual-balance differential signal circuit rejects plant electrical noise.
- Ex converter safely serves the classified solvent area.
Configuration used in this application
| Instrument | YF-W200D explosion-proof transit-time ultrasonic flow meter |
|---|---|
| Transducers | External clamp-on on stainless steel pipe |
| Line size / material | DN80 stainless steel |
| Fluid | Ethanol / industrial solvents, 10–40 °C |
| Accuracy | ±1% of reading |
| Flow velocity | 0.2–3 m/s |
| Outputs used | 4–20 mA to DCS, RS485 Modbus |
| Power | DC 24 V, 1.5 W |
How it is deployed
- Survey the pipe and confirm a 10D upstream / 5D downstream straight section.
- Clean and couple the clamp-on transducers to the stainless pipe.
- Fix the Ex converter and route the transducer cable to it.
- Enter pipe and fluid parameters, then validate signal and zero.
What the operator gets
- Continuous solvent flow data with zero fluid contact.
- Installation completed during normal production with no shutdown.
- Stable readings despite VFD and electrical noise in the plant.
- Safe Ex installation with no wetted parts to corrode.
Frequently asked questions
Can clamp-on ultrasound measure clean solvents accurately?
Yes. Clean, low-gas liquids such as alcohols and solvents are ideal for transit-time clamp-on measurement, giving ±1% of reading with adequate straight run.
Will the transducers be damaged by aggressive external environments?
The transducers are mounted on the outside of the pipe and do not contact the fluid; the converter is in the Ex enclosure. Suitable coupling and protection match the plant environment.
Is periodic re-coupling required?
Correctly installed clamp-on transducers with stable coupling provide long service; routine inspection is light and can be scheduled with normal maintenance.
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