Inline Ultrasonic Flow Meter

Factory-Calibrated Wafer + Flanged Pipe-Segment, DN15 to DN1200

Wafer body DN15-DN300 · flanged body DN350-DN1200
±0.5 % of rate factory-calibrated sealed unit
0 to ±12 m/s bi-directional · transit-time, no field straight-pipe penalty

  • Sealed flow-tube body with built-in transducer pair; factory calibration on known internal straight-pipe length removes the field 10D/5D rule
  • Reads DI, RO, glycol, hydrocarbon, and any low-conductivity liquid that electromagnetic cannot read
  • OEM volume buy: custom Modbus register map, custom 4-20 mA scaling, OEM-printed label, custom calibration certificate
↓ Request datasheet (PDF)
25.84 m3/h TX RX FLOW IN FLOW OUT WAFER FLANGE WAFER FLANGE Sealed flow-tube body · factory-calibrated as one unit DN15-DN1200 · ±0.5 % · wafer + flanged options · 5-7 days

The Inline Ultrasonic Flow Meter drops into the pipeline as a sealed flow-tube with built-in transducer pair, factory-calibrated to ±0.5 % of rate across DN15 to DN1200. Wafer body DN15-DN300; flanged in-line DN350-DN1200. Internal calibrated length cuts the field straight-pipe rule to 3D/2D. Transit-time reads DI, RO, glycol-water, and light hydrocarbon up to 10 cSt where EMF cannot. 4-20 mA × 2, Modbus RTU, M-BUS EN 13757; HART option. AC mains or DC 8-36 V. 5–7 business days.

Benefits

  • Factory-calibrated sealed flow-tube body; transducer pair built into the body; internal calibrated length cuts field rule to 3D/2D vs clamp-on 10D/5D.
  • DN15 to DN1200 single-Series; wafer DN15-DN300 (shortest face-to-face); flanged DN350-DN1200 (full-bore continuity). DN200-DN300 either style.
  • Reads any liquid above the noise floor regardless of conductivity; DI, RO, glycol-water, light hydrocarbon up to 10 cSt where EMF cannot read.
  • ±0.5 % of rate factory-calibrated; traceable to reference master meter; certificate ships with bench-tested velocity range and accuracy class.
  • Modbus RTU, M-BUS EN 13757, 4-20 mA × 2; Modbus for BMS; M-BUS for EU billing; 4-20 mA for SCADA + OEM skid. HART option.
  • AC 90-260 V universal + DC 8-36 V bus; global mains without rewiring; 24 V building control supply. IP65 transmitter + IP68 flow-tube body.
  • 5–7 business days factory-direct; ISO 9001 cal cert, EMC 2014/30/EU, mill-cert traceability. OEM volume supports custom register map, scaling, label, cert.

Configure your build.

Build a quotable model code from DN, body style, output, power, and accessory selection. Send the configured code with your pipeline context (medium, design pressure, BMS spec); the engineering team replies with a sized quote within one business day.

Your configuration

PF-UFM-IN-DN50-W-STD-A-304-AC
DN50 wafer body, standard medium-temp (-30 to +90 °C), 4-20 mA x 2 + Modbus + Pulse, 304 stainless body, AC 90-260 V universal mains.
Estimated unit price$ 1,180
Request engineering quote Request datasheet

Applications

🏭

Industrial process water

Plant cooling-water primary, tower makeup, condensate return, demineralized supply. Wafer DN50-DN200 replaces vortex / EMF on existing flanged lines. ±0.5 % cal suits ISO 50001 EnMS.

❄️

Chilled-water primary + condenser primary

HVAC chiller plant primary on new construction; flanged DN300-DN800 fits district-cooling headers. Glycol-water tolerance covers anti-freeze loops where EMF cannot read.

⚗️

DI / RO / low-conductivity process water

Pharma purified water, semicon fab DI, RO permeate, lab DI supply. Transit-time reads regardless of conductivity. 316L wetted parts on purified service.

📦

OEM skid integration

Factory-calibrated flow-tube drops into OEM skid (cooling tower, chiller cabinet, boiler, water-treatment). Volume buy 20-200; custom register map, 4-20 mA scaling, OEM label, cert at order.

Full specifications.

Measurement principleTransit-time ultrasonic, factory-calibrated sealed flow-tube body with built-in transducer pair on a fixed internal straight-pipe length
Nominal diameterDN15 to DN1200 (wafer body DN15-DN300; flanged in-line body DN350-DN1200; DN200-DN300 either body style)
Accuracy±0.5 % of rate (factory-calibrated as sealed unit, traceable to reference master meter)
Repeatability0.2 % of span
Velocity range0 to ±12 m/s, bi-directional with reverse-flow detection
Particulate tolerance≤ 10 000 ppm suspended solids
Medium temperature−30 to +90 °C standard; HT version −30 to +160 °C for boiler condensate + district-heat primary
Compatible mediaPotable / process water · DI / RO / low-conductivity water · glycol-water blends (30-50 % typical) · light hydrocarbon up to 10 cSt viscosity · treated cooling-tower water · demineralized lab supply
Body material304 stainless standard · 316L stainless corrosion-resistant · carbon steel + epoxy lining cost-down industrial water
ConnectionWafer between ANSI 150 / PN16 / DIN flanges · flanged in-line ANSI 150 / 300 + PN10 / PN16 / PN25
DisplayLCD multi-line readout showing instantaneous flow, totalizer, alarm status, diagnostics; 500 ms update rate per UFM family standard
Output signals4-20 mA × 2 (0.1 % accuracy) · RS-485 Modbus RTU · M-BUS EN 13757 · HART (factory option) · Pulse OCT
BMS integrationModbus native · BACnet via Modbus gateway · KNX via converter · LonWorks via gateway · M-BUS direct EN 13757
Power supplyAC 90-260 V universal mains · DC 8-36 V industrial bus
Power consumption2 W typical
Ingress protectionIP65 transmitter housing · IP68 flow-tube body
Hazardous areaEx d available as factory custom build (NOT a standard option)
Install rule3D minimum free-pipe upstream / 2D downstream from meter inlet/outlet flanges (~1/3 the footprint of clamp-on field rule)
OEM optionsCustom Modbus register map · custom 4-20 mA scaling · OEM-printed label · custom calibration certificate · volume-buy 20-200 units
Compliance ships standardISO 9001 calibration certificate with each meter · EMC 2014/30/EU · mill-cert traceability on body material
Custody-transfer certification (buyer-arranged, not shipped from factory)OIML R75 heat metering · MID EU custody · AGA-9 North American pipeline (all NOT shipped from factory)
Lead time5 to 7 business days from factory

Installation rules.

  1. Maintain 3D upstream / 2D downstream free pipe from flanges. A 90° elbow within 1D introduces profile asymmetry.
  2. Verify pipe-fill before measurement. Pipe must stay 100 % liquid-filled; air pockets falsify the signal. Use an air vent on the loop high point or mount on vertical-upward.
  3. Align flow direction with the direction arrow on the body. Reverse-flow detection works, but mounting against the arrow inverts the reading; verify direction at commissioning.
  4. Torque flange bolts evenly to gasket spec. Wafer body needs even torque to avoid distorting the body and shifting transducer alignment. Star pattern with a torque wrench.
  5. Calibrate the Modbus register map and slave address at commissioning. Factory pre-configures from BMS spec; OEM skids ship pre-configured plug-and-play.

Frequently asked questions

Inline vs clamp-on ultrasonic flow meter; which one fits my application?+
Inline (this product) is a sealed flow-tube body that drops into the pipe line as a pipe segment, factory-calibrated as a unit. Pick inline when the application is new construction, when the install allows a flanged or wafer pipe-segment insertion, and when the buyer needs the precision that comes from factory calibration on a known straight-pipe length inside the body. Clamp-on is the external-mount counterpart that retrofits on existing pipes without cut; pick clamp-on when the pipe is already in place, when shutdown is not acceptable, or when the host pipe diameter exceeds DN1200 (clamp-on goes to DN6000 via L transducer). Same transit-time physics on both; different install style.
Wafer vs flanged body; which one and at what DN?+
Wafer body fits between two flanges of the host pipeline, secured by long studs through both flanges and the wafer body; the shortest face-to-face dimension, fits DN15 to DN300 typical. Flanged in-line body has its own ANSI 150 / PN16 flanges bolted to the host flanges (longer face-to-face dimension, full-bore flow path), serves DN350 to DN1200. For DN200 to DN300 either option is available; wafer wins on cost and on shorter installed length; flanged wins on easier maintenance access and on full-bore continuity. Specify body style at order based on the host pipeline configuration.
How does factory calibration remove the field straight-pipe rule?+
The inline flow-tube body includes a calibrated straight-pipe length upstream and downstream of the transducer pair inside the sealed body. The factory calibration table is built on this fixed geometry, so the field installer only needs to bolt the meter into the line without managing 10D upstream / 5D downstream straight-pipe rule against external elbows and valves. The exception is severe disturbance immediately upstream; a 90-degree elbow within one pipe diameter of the meter inlet flange still introduces profile asymmetry that the internal calibrated length cannot fully cancel. Install rule: maintain 3D minimum free-pipe upstream and 2D downstream from the meter inlet/outlet flanges; this is roughly 1/3 the straight-pipe footprint of a clamp-on retrofit on the same line.
Can the inline meter handle DI water, RO water, glycol blends, and other low-conductivity liquids?+
Yes. Transit-time ultrasonic is independent of fluid conductivity; the sound transit-time signal works regardless of whether the medium is conductive water (potable, wastewater, cooling water) or non-conductive (DI water, RO water, glycol-water blends, light hydrocarbon, mineral oil up to 10 cSt viscosity). This is the structural difference from electromagnetic flow meters which require >=5 microS/cm conductivity floor. For closed-loop HVAC chilled-water systems running on treated low-conductivity water + corrosion-inhibitor packages, electromagnetic cannot read; inline ultrasonic is the right pick. For solvent-grade hydrocarbon above 10 cSt viscosity, go to Coriolis (ZLMFM) family instead.
Does the inline meter integrate with OEM skid + BMS + SCADA equally well?+
Yes; three native integration interfaces. 4-20 mA loop output (two channels, 0.1 % accuracy) feeds plant SCADA + OEM skid PLC analog-input racks. RS-485 Modbus RTU exposes flow rate, totalizer, alarm, and diagnostics over serial for direct BMS or Modbus polling. M-BUS output meets EN 13757 European HVAC billing compliance for tenant chargeback installations. HART overlay is a factory option for HART-multiplexer fields. OEM volume buy supports custom Modbus register map, custom slave address, custom 4-20 mA scaling, and OEM-printed label at order. The flow-tube body geometry fits standard ANSI 150 / PN16 / DIN flange patterns common to OEM skid plumbing.
What is the velocity range, and where does the accuracy range start to relax?+
Velocity range is 0 to plus-minus 12 m/s bi-directional. Accuracy holds at plus-minus 0.5 % of rate across the calibrated range from 0.3 to 10 m/s; at very low velocity (below 0.1 m/s) the transit-time difference signal approaches the sensor noise floor and accuracy relaxes to plus-minus 1.0 % of rate; at very high velocity (above 10 m/s) flow-tube vibration and turbulence cause repeatability to relax to 0.5 % of span. For sub-0.1 m/s low-flow audit applications, go to the clamp-on portable version with longer-integration signal processing instead.
What is the lead time, and what calibration certificate ships with the meter?+
Standard lead time is 5 to 7 business days from order confirmation, factory direct. Each meter ships with an ISO 9001 calibration certificate listing the serial number, factory calibration table tested at the bench against a reference master meter, the calibrated velocity range, and the tested accuracy class. EMC 2014/30/EU compliance certificate ships standard. Mill-cert traceability note covers the flow-tube body material (304 / 316L stainless standard; carbon steel ASTM A53 + epoxy-lined option for cost-sensitive industrial water) and the wetted-parts heat-number traceability back to the steel mill. OIML R75, MID, and AGA-9 are buyer-arranged with the local notified body.

Need help spec’ing the build?

Send DN, body style, medium, design pressure, and BMS target. Engineering replies with transducer pair, body style, and quote in one business day.