At the end of 2017 there was more activity than usual at Litre Meter as some of the largest VFF meters were gathered together for assembly and calibration. A complex project involving 7 different VFF sizes including the largest ever VFF was nearing completion. The V400 weighs a hefty 600kg and measures a suitably massive flow rate of 330 l/min and is designed for 19m³/h normal flow. The liquid is lean MEG (monoethylene glycol) which is used as an antifreeze in offshore production platforms, amongst others. The VFF series normally tops out at 2″ connections so 6″ was quite an engineering and logistical task.
The pressure rating of 260+bar and the customer’s 6″ line dictated the use of 6″ANSI2500 connections and a 316L body. On top of this is the standard chemical injection instrument, the FlowPod, which provides a clear display, 2 wire operation and HART all in a 316 Exd enclosure.
Other meter sizes included a V270 for methanol measurement, several HF60s also for methanol and an LF03 measuring just 0.5 litres per hour of antifoam (40,000 to one range from the smallest to the largest, in case you’re wondering). They all use the VFF rotary piston technology with pressure balanced chambers to ensure accurate measurement independent of operating pressure. The range of displacements is from 0.4ml up to around 860 ml.
Connection ratings were equally disparate, ranging from ANSI150 to API6A, matching pressure ratings from 16.5 to 690bar.
Litre Meter CEO Charles Wemyss said: “Many new technologies provide superb measurement at various pressures, flow rates and operating conditions but lack the ability to provide measurement when the going gets tough, the pressures get high and the rates get low, or in this case when the rate gets high. For super low flows at challenging pressures, or when pulsing flow can’t be tamed, the VFF comes out on top.
“Hydrate, scale and corrosion prevention strategies provide protection during normal operation, start-up and shutdown.
“Litre Meter’s VFF flowmeter is ideally suited for use in the oil and gas industry and in particular for low flow / high pressure applications.
“Years of experience in chemical injection applications onshore and offshore have confirmed the instrument’s capability to reliably measure fluids under extreme conditions of both flow and pressure.”