Forbes Marshall FLOWIRL 8400 Vortex Flowmeter

Overview

The Forbes Marshall FLOWIRL 8400 is an all-in-one vortex flowmeter that Forbes Marshall offers for the measurement of saturated and superheated steam, industrial gases, compressed air and liquids. It is designed to cope with fluctuating pressures and temperatures, making it a strong choice for metering energy carriers in auxiliary and supply processes. The basic version includes temperature compensation for saturated steam, an optional integrated pressure sensor adds full density compensation for gases and superheated steam, and built-in gross and net heat calculation supports energy management systems.

Seven Star LLC supplies the Forbes Marshall FLOWIRL 8400 to boiler operators, utilities engineers and energy managers in Oman and the GCC, with engineering support in Muscat. Steam and compressed air are among the largest hidden energy costs in a plant, and measuring them accurately at each consumer is the first step to the savings that steam system audits identify.

Measurement Principle

The Forbes Marshall FLOWIRL 8400 works on the Karman vortex street principle. A bluff body placed across the measuring tube sheds vortices alternately from each side as fluid flows past it, and a sensor located behind the bluff body detects them. The shedding frequency f is proportional to the flow velocity v, and the relationship is described by the dimensionless Strouhal number S and the width b of the bluff body: f = S × v / b. The signal converter evaluates the vortex frequency to calculate operating and standard volume flow and mass flow.

Real plants generate pipe vibration and hydraulic noise that can disturb a vortex signal. The meter therefore uses Advanced Vortex Frequency Detection (AVFD), a signal filtering technology that improves noise immunity and keeps the reading stable. With the optional pressure sensor, volume flow, pressure and temperature are all measured at a single point, so mass flow is computed directly and the errors that come from separate, distant sensors are avoided. There are no moving parts in the flow path.

Engineering Design of the Forbes Marshall FLOWIRL 8400

The Forbes Marshall FLOWIRL 8400 is available as a compact flange version with integrated temperature measurement, as a sandwich (wafer) version with optimised centring rings that can be turned to align the meter exactly with the pipeline, and as a remote version in which the signal converter sits in a field housing up to 50 m (164 ft) from the flow sensor. The F1R and F2R flange versions integrate a reduction of one or two nominal sizes, which improves low-flow accuracy in large lines without separate reducers. The flow sensor and process connections are 316L stainless steel and the electronics housing is die-cast aluminium with a two-layer epoxy/polyester coating.

Flange connections cover DN15 to DN300 at PN16 to PN100 to EN 1092-1, and 1/2 to 12 inch at Class 150 to 600 to ASME B16.5; sandwich versions cover DN15 to DN100 at PN100 and 1/2 to 4 inch at Class 600. The meter is a 2-wire device powered from 12-36 VDC, with a passive 4-20 mA HART 7 output, a passive binary output for pulse, frequency, status or limit switch, and a passive 4-20 mA current input. Ingress protection is IP66/67 for the compact housing and for both remote housings, and IBR approval is listed for steam systems.

Key Features

Engineers choose the Forbes Marshall FLOWIRL 8400 for these reasons:

• One meter measures conductive and non-conductive liquids, gases, saturated steam and superheated steam.
• Temperature compensation for saturated steam is standard, giving mass and energy flow without extra sensors.
• Optional integrated pressure and temperature compensation removes separate transmitters and cabling.
• AVFD signal filtering provides better noise immunity in vibrating installations.
• F1R and F2R integrated diameter reduction gives accurate results in large lines with low flow.
• Remote converter option allows mounting up to 50 m from the sensor for reading at eye level.
• Accuracy of 0.75% for liquids and 1.5% for steam and gas mass flow, with 0.1% repeatability.
• Medium temperature from -40 to +240°C and pressure up to 100 bar, with IP66/67 housings.

Industrial Applications

Forbes Marshall lists saturated and superheated steam measurement, steam boiler monitoring, industrial gas consumption, compressed air consumption, compressor output monitoring, free air delivery evaluation, and SIP and CIP processes in food, beverage and pharmaceutical plants as typical applications. In Oman the Forbes Marshall FLOWIRL 8400 fits boiler outlet and header steam metering in refineries, fertiliser and petrochemical plants in Sohar, departmental steam metering in food and dairy plants, and compressed air audits in manufacturing sites in Rusayl and Nizwa industrial estates.

For energy managers, the integrated heat calculation allows boiler efficiency and specific steam consumption to be tracked from the meter itself. Seven Star LLC supplies the Forbes Marshall FLOWIRL 8400 with application support from Muscat, helping customers across the GCC size the meter, choose between standard and reduced-bore versions, and plan the straight pipe runs that the brochure specifies.

Technical Specifications

The Forbes Marshall FLOWIRL 8400 data below is taken from the Forbes Marshall FLOWIRL 8400 brochure.

Compare with the Rosemount 8800D vortex flowmeter, the Yokogawa VF701 vortex flowmeter and the Spirax Sarco TVA steam target flowmeter.

How to Order

To order the Forbes Marshall FLOWIRL 8400, send Seven Star LLC a formal RFQ with the medium, line size, flange rating, operating pressure and temperature and the expected flow range, and our instrumentation team will confirm the configuration. We offer supply on request and engineering support in Muscat for customers in Oman and the GCC. Download the Forbes Marshall FLOWIRL 8400 brochure from this page, and contact our flow measurement division for sizing and delivery times.