Flow Transmitters
Materials Selection
Litre Meter flowmeters are constructed from very high quality materials to meet the requirements of the Chemical, Pharmaceutical and Process Industries. However, the meters may be economically applied for many less demanding applications. This is due to the excellent cost-effectiveness of the meter's construction.
The meter rotor is normally manufactured in plastic with ferrites that are sensed by the meter pick-up system. These ferrites may be sealed when the rotor is constructed from PFA (perfluoroalkoxy), PVDF, Glass- filled Nylon or Glass-filled polypropylene. PFA (Teflon) has an effectively similar chemical resistance to PTFE (Teflon) for use to 135°C. Optional sealing of the rotor ferrites is normally recommended for fluids that are aggressive to metals.
MM Series 100 bar meters have a PTFE meter cap/body seal. Other meters are equipped with an O-Ring seal, which is fluoropolymer (FPM) as standard. Alternatives are ethylene-propylene rubber (EPDM), chemically-resistant PTFE covered silicon, Kalrez and many others. Very high pressure meters usually have metal O-Rings in silver plated Inconel or PTFE coated 316.
Special Materials Of Construction And Design
Litre Meter supply chemically-resistant flowmeters constructed entirely from titanium, PFA, PVDF, PP or PVC except for the precision sapphire bearings. The meters can be constructed with special pipework arrangements such as fusion welding, flanged or screwed connections as appropriate. Meters from high-purity 440 PFA material offer minimal 'parts per billion' process fluid contamination.
To meet the highest pressure applications, 316 stainless steel is normally used and the meters can be suitable for up to API 6BX 1380 bar flange mounting, screwed or compression fittings. Particular aspects of Quality Assurance can be specified including non-destructive testing, and of course material certificates.
Meters with titanium turbine ring assemblies are used for the highest concentrations of Nitric Acids or Sea-water, for example. For Sea-water service a gun-metal body can be offered. Special stainless steel meters are available with hygienic end connections.
The specialist team at Litre Meter are happy to offer advice concerning the selection of the most suitable materials for difficult measurement problems. Meters can be engineered to meet individual installation circumstances as part of our comprehensive service.