VFF Rotary Piston PD Flow Meter is ideal for use in applications with very low flow rates and high pressures, such as offshore chemical injection applications.
The VFF Rotary Piston Positive Displacement Flow Meter is designed for very low flow rates (as low as 0.049 gallons/day) and high pressures (up to 60,000 psi) of oils, hydraulic fluids, corrosion, wax, scale, and hydrate inhibitors, biocides, and oxygen scavengers used in the offshore oil recovery industry. The high grade materials used in the construction of the meter bodies, allow these PD meters to resist chemical and environmental corrosion. The VFF flow meter also provides exceptional rangeability with potential turndowns of up to 3000:1.
The VFF has successfully metered for over 30 years fluids such as oils, hydraulic fluids, corrosion / wax / scale / hydrate inhibitors, biocides, oxygen scavengers, etc. Meter bodies are produced in a variety of high grade materials which offer good chemical and environmental resistance.
Applications for flow-rates as low 0.00013 litre/min (0.19 litres/day) have been metered within the offshore oil industry. The VFF flow meter provides exceptional range ability with potential turndowns of up to 3000:1, dependent on operating viscosity.
The meters range in size from the smallest standard stock size, LF05 – 30 L/hr max, to the largest V270 – 270 L/min max. Higher flow-rate meters may be available to special order. An extensive range of meter construction offers pressure ratings from 0 to 1380 bar (20,000 PSI) suitable for most industrial applications and special higher pressure rating designs are manufactured up to 4000 bar.
Technical Specification :
MEASURING ACCURACY : ± 1% of reading, requires linearization.
FLOW MEASURING RANGES :
- 0 to 114 gal/day (0 to 18 L/hr)
- 0 to 190 gal/day (0 to 30 L/hr)
- 0 to 570 gal/day (0 to 90 L/hr)
- 0 to 1141 gal/day (0 to 180 L/hr)
- 0 to 2536 gal/day (0 to 400 L/hr)
- 0 to 5072 gal/day (0 to 800 L/hr)
- 0 to 5.3 GPM (0 to 20 L/min)
- 0 to 10 GPM (0 to 40 L/min)
- 0 to 16 GPM (0 to 60 L/min)
- 0 to 33 GPM (0 to 125 L/min)
- 0 to 71 GPM (0 to 270 L/min)
MAXIMUM OPERATING PRESSURE : up to 60,000 psi (4000 bar).
MAXIMUM FLUID TEMPERATURE : -40 to 100°C with remote-mounted electronics.
PORTS : NPT standard, BSPP available.
MATERIALS OF CONSTRUCTION : Available in 316L, Duplex F51(UNS S31803), Super Duplex F53(UNS S32750)/F55(UNS S32760). 6Mo F44 (UNS S31254) & Titanium.
Internals : Constructed of either Nitronic-60 (antigalling) or Titanium for the LF03, LF05 & LF15 size to achieve the lowest flow and widest turndown possible. Chambers and rotors are PVD coated. Coatings are applied by physical vapour deposition. A hard metal chromium nitride base layer provides surface hardness and appropriate support for the carbon (WC/C) which is laid over. The WC/C coating provides excellent protection against adhesive wear and its low coefficient of friction reduces the risk of surface fatigue (pitting) and fretting corrosion, vastly improving turndown and low flow capability.
Seal : There is a single FPM O-ring pressure seal between the top cap and body and a FPM seal between internal chamber and body. Other elastomers are available e.g. FFKM, FEP covered silicon and in higher pressure versions PTFE and Inconel. Other seals are internal to the body and materials will be selected dependent on the fluid.
Connections : NPT threaded connections are standard for lower pressure versions, Autoclave Medium Pressure fittings (cone & thread) are standard for higher ratings. ANSI flanges in raised face and ring type joint also available. Hubs such as Grayloc, Galperti, Techlok and more are available on request.
Sensor : Two reed switches in one single compact sensor housing that can be set for reverse flow detection or redundancy. Tested for over 1 billion pulses.
Accuracy : 1% of reading, requires linearisation. Provided by all Litre Meter instrumentation.
Viscosity : 0.5 – 100,000 cSt or greater.
Temperature rating : -40 oC – 100 oC with remote mounted electronics. For direct mount versions see next page. Higher temperature special versions available on request.
Filtration : A 100 micron filter is advisable for 100% long life serviceability. For LF03 & LF05 size a 40 micron filter is recommended.