pFlow D118 Clamp-On Ultrasonic Flow Meter

Overview

The pFlow D118 is a wall-mounted, clamp-on transit-time ultrasonic flow meter engineered for accurate, non-invasive liquid flow measurement across water treatment, utility and process applications. Built on low-voltage broadband pulse transmission and the manufacturer’s TVT signal-processing technology, the pFlow D118 delivers ±0.5% accuracy of measured value on pipe sizes from 25 mm to 5000 mm without ever breaking into the pipeline. Because the transducers clamp onto the outside of the pipe, the meter introduces no pressure drop, no leak path and no wetted parts — a decisive advantage in treated-water, potable and effluent lines where hygiene and pipeline integrity cannot be compromised.

As the official authorized partner and exclusive regional representative for pFlow, Seven Star LLC proudly supplies the pFlow D118 throughout the Sultanate of Oman and the wider GCC with full manufacturer warranty, factory-calibrated transducers and local engineering support. Units are deployed across municipal water networks in Muscat, desalination and reverse-osmosis plants along the Batinah coast, and industrial utilities in the Sohar and Salalah economic zones, where the combination of clamp-on installation and RS485 MODBUS integration allows plants to add reliable flow metering to live systems without a shutdown.

Measurement Principle of the pFlow D118

The pFlow D118 operates on the transit-time differential principle. A pair of encapsulated ultrasonic transducers is clamped to the pipe exterior, and each transducer alternately transmits and receives an ultrasonic pulse that crosses the liquid at a diagonal to the flow axis. A pulse travelling downstream is carried along by the moving liquid and arrives fractionally sooner than a pulse travelling upstream against it. The meter measures this transit-time difference to nanosecond resolution, and because the difference is directly proportional to the mean velocity of the liquid along the acoustic path, the instrument resolves velocity over a bidirectional range of ±0.01 to ±12 m/s with 0.1% repeatability.

Volumetric flow is then derived from the measured velocity and the internal cross-sectional area of the pipe, which the operator enters as pipe outside diameter, wall thickness and material during commissioning. Low-voltage broadband pulse transmission gives the pFlow D118 a strong signal-to-noise margin, so the instrument remains stable on liquids carrying small quantities of entrained air or suspended solids typical of industrial and wastewater service. The practical consequences of this measurement approach matter to any plant engineer: there are no moving parts to wear or seize, no obstruction and therefore no permanent pressure loss, no risk of contaminating the process fluid, and no need to drain, cut or weld the line to install the instrument.

Engineering Design of the pFlow D118

The transmitter of the pFlow D118 is housed in a die-cast aluminium enclosure rated IP65, suitable for permanent installation in plant rooms, pump houses and outdoor utility cabinets across the Gulf climate. The operator interface combines a 20 × 2 lattice alphanumeric backlit LCD with a 22-key light tactile keyboard, giving direct menu-driven access to configuration, diagnostics and totaliser data without proprietary software or a laptop. A standard SD card slot logs up to 512 days of data at a user-selectable interval of 1 to 3600 seconds, so historical flow records survive independently of the plant SCADA system.

Field wiring is straightforward once the enclosure is mounted: the power board presents clearly ordered terminals for AC supply (90–245 VAC), DC supply (10–36 VDC), relay output, OCT pulse output, analogue input, transducer connection, 4–20 mA output, RS232 and RS485. The encapsulated transducers ship with 9 m of double-shielded cable and can be extended to 305 m where the transmitter must sit remote from the measuring point. Two mounting geometries are supported — the Z method for pipes from 50 mm to 5000 mm, preferred on heavily scaled or corroded pipe because of its stronger signal path, and the V method for 300 mm to 1200 mm pipes where only one side of the pipe is accessible.

Key Features

The following features define the pFlow D118 and explain why it is specified so widely on water and utility projects across Oman:

• Clamp-on transit-time measurement delivers ±0.5% accuracy of measured value with 0.1% repeatability and requires no pipe cutting, welding or process shutdown.
• An exceptionally wide pipe range of 25 mm to 5000 mm allows a single instrument model to be standardised across small process lines and large municipal mains.
• Bidirectional measurement covers ±0.01 to ±12 m/s and reports positive, negative and net totalised flow in parallel with a 7-digit display and scale factor.
• TVT signal-processing technology with low-voltage broadband pulse transmission maintains a stable reading on liquids containing small amounts of air bubbles or suspended solids.
• A complete output set — 0/4–20 mA analogue into a maximum 750 Ω load, 0–9999 Hz OCT pulse and a 1 Hz relay — integrates the meter into existing DCS, PLC and BMS architectures.
• RS232 and RS485 communication interfaces with MODBUS support allow the pFlow D118 to be polled directly by plant SCADA and energy-management platforms.
• A standard SD card records up to 512 days of flow history at intervals from 1 to 3600 seconds, providing an independent audit trail for billing and compliance reporting.
• Dual-supply flexibility of 90–245 VAC or 10–36 VDC, an IP65 die-cast aluminium transmitter and transducers rated to 80 °C suit the instrument to demanding Gulf installations.

Industrial Applications

The pFlow D118 is applied wherever accurate liquid flow data is required without interrupting the process. In municipal and industrial water treatment it monitors raw intake, filtration throughput, backwash and final effluent lines; in reverse-osmosis and desalination plants it meters feed, permeate and brine streams where wetted metering hardware would be attacked by chloride corrosion. District cooling schemes and commercial HVAC systems across Muscat use the instrument on chilled-water risers and condenser circuits to verify design flow and support energy audits, while process industries — chemical, pharmaceutical, and food and beverage — rely on its non-invasive nature to preserve product purity and sanitary pipework.

As the officially authorized partner for pFlow, Seven Star LLC distributes the pFlow D118 to hospital complexes, hotel and hospitality chains, agricultural and irrigation networks, and heavy industrial facilities throughout the Sohar and Salalah economic zones. The instrument is equally valuable as a permanent installation and as a diagnostic reference for maintenance teams troubleshooting suspect inline meters, balancing pump circuits or building a baseline before a plant efficiency project. Regional clients specify the pFlow D118 because it can be commissioned on a live line in a single shift, with no civil work, no pipe spool fabrication and no production loss.

Technical Specifications

The verified manufacturer specifications for the pFlow D118 are summarised below:

Call To Action

Seven Star LLC supplies the pFlow D118 clamp-on ultrasonic flow meter with formal RFQ support, competitive project pricing and regional warehouse stock for short lead times. Submit a request for quotation for single units or multi-site project quantities, ask our instrumentation division for the full technical datasheet and transducer selection guidance, or arrange a site survey to confirm pipe compatibility before ordering. As the authorized partner for pFlow in Oman and the GCC, Seven Star LLC provides genuine factory-supplied instruments, full manufacturer warranty, commissioning assistance and after-sales technical support. Contact our instrumentation team today to specify the pFlow D118 for your water treatment, HVAC or process metering application.