Litre Meter have been making meters for higher pressures for over 3 decades. Our first 1,380bar unit was shipped in 1997. We’ve now produced a brochure to cover these ratings.
Litre Meter have been manufacturing flowmeters since 1975. We’ve always concentrated on the harder margins of metering typically at low flows and/or at high pressure. The VFF range has many uses in the oil and gas industry and meets the high specifications required. Outside of oil and gas we have manufactured these to 2,500 bar. We have recently noticed a trend towards 20,000 psi ratings and this brochure is in response to that.
Since 1997 we have made numerous VFF meters for 1,380 bar in Oil and Gas applications and a reference list is provided at the end of this article.
The same design can be used on 22.5ksi (1,550 bar) with little modification.
The breakthrough in our design philosophy came when we separated the measurement of the fluid from the pressure containment. We designed a measurement chamber that floats in the pressure vessel. This ensures accurate, pressure independent flow metering from 10 psi to 20,000 psi. The Pressure Balance Chamber is explained below.
- Rotary Piston/ Oscillating Piston type flow meter with a single
moving part provides robust and low maintenance technology.
- Suitable for low & high viscosity liquids at pressure ratings up to
4,000 bar (60,000 psi). 20,000 psi designs as standard.
- Available materials of construction: 316L (UNS S31603), Duplex F51(UNS S31803), Super Duplex F53(UNS S32750)/F55(UNS S32760), 6Mo F44(UNS S31254), Hastelloy (UNS N10276) & Titanium (UNS R56400).
- Connections: Autoclave, Grayloc Hubs, Galperti Hubs, Techlok hubs. More on request.
- Communications: 4‐20mA HART, Pulse, MODBUS, Foundation Fieldbus, dependent on electronics and certification requirements.
- Very Low Flow Measurement
- Tolerant of particulate up to 100+ microns
- Low pressure drop (<0.1 bar typical)
20K Flowmeters ‐ Applications and Rates
The VFF has successfully metered fluids such as oils, hydraulic fluids, corrosion / wax / demulsifier / pour point depressant /scale / hydrate inhibitors, biocides, oxygen scavengers, etc. for over 30 years. 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 litres/min (0.19 litres/day) have been metered within the offshore oil industry. The VFF flow meter provides exceptional rangeability with potential turndowns of up to 3000:1, dependent on operating viscosity.
The meters range in size from the smallest standard stock size, LF03 ‐ 18 L/Hr max, to the largest V270 ‐ 270 L/min max. Higher flow‐rate meters are available to special order.
An extensive range of meter designs and materials offers pressure ratings to 20,000 psi (1,380 bar). Higher pressure rating designs are manufactured up to 4,000 bar (60,000 psi). 20,000 psi designs available, as standard, up to HF60 and special designs can measure higher flow rates.
20K Flowmeters ‐ Meter Sizes
The VFF meter is not just one size, one specification. It’s a comprehensive range of carefully engineered devices to meet today’s standards in the most demanding oil & gas arenas. It’s truly a Versatile Fluids Flowmeter.
In the illustration below the smallest meter is typically housing an LF05 or LF15 rotor and chamber with FlowPod instrument and Autoclave Engineers MP connections.
The middle unit is a medium size meter, say, VFF4 with hub connections and FlowPod display.
The right‐hand meter also has hubbed connection sizes, FlowPod display but is larger to accommodates the HF60 rotor and chamber.
Pressure Balance Chamber
What Is a Pressure Balance Chamber?
Extensive testing by Litre Meter in 2005 proved that leaks occur over the top of the rotor at higher pressures. This is due to minute distortions of the cap. For example, at 700 bar the cap moves by just 0.02mm in the centre. Increasing the bulk of the cap still produces this movement. The effect on meter performance was the creation of a leak path for fluid that avoided the positive displacement of the rotor. This was equivalent to about a 3% inaccuracy at 700 bar. As a result, of this Litre Meter designed a pressure balance chamber for its VFF flowmeters so it could operate at extreme pressure and at low flow rates. The pressure balance chamber acts as a barrier, protecting the internal measurement components of the instrument from the high pressure conditions, preventing them from expanding and contracting under the immense pressure. NO DISTORTION MEANS ACCURATE MEASUREMENT AT ANY PRESSURE. All VFFs over 414 bar are fitted with this technology. It is identified by the letters PBC in the calibration certificate.
- No distortion of the chamber at higher pressures.
- Enables selection of optimal materials for the chamber to match the rotor i.e. PVD coated stainless steel or titanium.
- Enables selection of optimal materials for the pressure vessel.
- Enables construction of a duplex bodied flowmeter.
- Swappable PBC for simplified sparing.
Flow ranges and references
All VFF flowmeters are custom calibrated across the customer specified min – max flow conditions and working viscosity. The minimum flow rates achievable are dependent on fluid viscosity. To see the achievable calibration ranges for each meter size please consult the table below. We can offer meters that range from 0.005 L/hr to 3,600 L/hr at 20K pressures to best suit your applications and with exceptional turndowns.
Areas of key significance:
- Extended experience in measuring 20,000 psi in Oil & Gas applications.
- World leaders in low flow and high pressure measurement.
- High or low viscosity fluids flow measurement.
- The Chemical Injection Specialists.
Litre Meter have already provided meters for 2,500bar. Offshore models at 22.5K, 25K, 30K, 40K and 50K will be produced.
Litre Meter continues to innovate in the field of flow measurement. Recent successes include the LF05 and LF03 size meters, a new sensor, the FlowPod instrument and the FlowLabPro calibrator series. In the near term, expect to see lower flow capabilities, more calibrators and a low flow meter for any liquid type.