Flow Control

Litre Meter specialise in the design, manufacture and supply of flowmeters. The unique Pelton wheel based meter design ensures an inherent reliability which has been proven in more than three decades of operation. Listed below are all the flow meters within our range that are suitable for flow control in the UK:


Pelton Wheel Also known as a radial turbine the highly efficient Pelton Wheel meter has some major advantages. The very large blade area compared with the flow inlet port size produces an exceptionally wide range flowmeter which can measure very low flows. The flow through the inlet of the meter is accurately directed onto the rotor which rotates at a speed in linear proportion to the flow rate. A small sensing coil detects the ferrites mounted in the flow meter rotor blade tips as they pass. No drag is imposed on the rotor which assists in the measurement of extremely low flows. Sapphire bearings provide a very low friction mechanically-robust bearing with long life characteristics. Turndown can be as high as 280:1. Ideally suited for low viscosity process liquids measurement up to 2" pipe sizes and larger and up to 10cSt. 0.003 to 500 l/min; ±2.0% of reading (also 1.0%); some models suitable for flow measurement at higher pressure.
Thermal Mass Capillary The Capillary Thermal principal of operation is based on heat transfer and the first law of thermodynamics. During operation, process gas enters the instrument’s flow body and it divides into two flow paths. The vast majority of the gas flow passes through the Laminar Flow Element (LFE) bypass. A very small portion of the total flow is diverted through a small “Capillary” sensor tube with an ID between .007 to .028 inches. This technology is ideal for gas flow measurement and gas flow control. Flowmeter accuracy: ±1% of full scale. From 0.1 to 4 sccm up to 1000 slpm.
Ultrasonic Ultrasonic flowmeters measure the travelling times (transit time models) or the frequency shifts (Doppler models) of ultrasonic waves in a pre-configured acoustic field that the flow is passing through to determine the flow velocity. The Sierra range of ultrasonic (transit time) Innovasonic devices are available, click for details. Litre Meter has access to other ranges but the Innovasonic is relatively unique as not only are fixed and portable ultrasonics available but also insertion devices for tougher applications. Ultrasonic flow meters can measure water and other liquids over a range of velocities and with a certain amount of solid content. 25mm to 10000mm;±1.0% of reading (also 0.5%); 0 to ±40 ft/s (0 to ±12 m/s).
Turbine Inline ‘axial’ turbine flowmeters are velocity measuring devices - they measure the average velocity of a fluid flowing through the body of the meter. Mounted within the body of a gas turbine flowmeter is a vaned rotor. The rotor is centred on a shaft and allowed to rotate on bearings. The shaft is supported in the housing by tube bundles that also provide a measure of flow conditioning for the fluid stream. Good for gas flow metering particularly at higher pressures. 0.15 to 3.5 up to 200 to 12,000 ACFM. ±1% reading - typical. ±0.25% repeatability. Also suitable for water, fuel and oil flow metering. Wide size range and excellent accuracy. 0.24-17 up to 3028-56775 litres/min. Overrange 150% intermittent. ±0.25% reading - typical. ±0.1% repeatability.
Electromagnetic Magnetic flowmeters, also known as electromagnetic flowmeters or induction flowmeters, obtain the flow velocity by measuring the changes of induced voltage of the conductive fluid passing across a controlled magnetic field. The fluid has to be conductive so tap water and waste water are OK. Care has to be taken in measuring solvents, hydrocarbons, de-ionised and demineralised water where electromagnetic flow meters are not normally used due to low conductivity. Contact Litre Meter for full details. 3mm to 2000mm although insertion units can be used up to 3000mm. ±0.2% over flow range 0.5 to 5 m/s; turndown 1000:1; maximum velocity 10 m/s.
Helical Screw

Positive displacement flowmeters, also known as PD meters, measure volumes of fluid flowing through by counting repeatedly the filling and discharging of known fixed volumes. A typical positive displacement flowmeter comprises a chamber that obstructs the flow. Inside the chamber, a rotating/reciprocating mechanical unit is placed to create fixed-volume discrete parcels from the passing fluid. The helical screw principle uses 2 counter rotating gears to form a continuous constant volume cavity.  The SRZ series is available exclusively in stainless steel.