Fluid Menu

Low Viscosity Liquids - Pelton

Selection

Flow Transmitters

Type	Pipe Size		L/min	m3/h	Gal/min
LM003	9mm	1/4"	0.004 - 0.060	0.00024 - 0.0036	0.0009 - 0.013
LM005	9mm	1/4"	0.006 - 0.100	0.00036 - 0.006	0.0013 - 0.022
LM01	9mm	1/4"	0.01 - 0.25	0.0006 - 0.015	0.002 - 0.055
LM05	9mm	1/4"	0.02 - 1.3	0.0012 - 0.078	0.004 - 0.29
LM24	9mm	1/4"	0.03 - 4.3	0.0018 - 0.258	0.007 - 0.95
LM45	9mm	1/4"	0.04 - 6.3	0.0024 - 0.378	0.009 - 1.39
LM90	9mm	1/4"	0.08 - 15	0.0048 - 0.9	0.0176 - 0.30
LM220	9mm	1/4"	0.1 - 28	0.006 - 1.68	0.022 - 6.17
MM 12.5	12.5mm	1/2"	1 - 65	0.06 - 3.90	0.22 - 14.32
MM20	20mm	3/4"	2 - 130	0.12 - 7.80	0.44 - 28.63
MM25	25mm	1"	3 - 160	0.18 - 9.60	0.66 - 35.24
MM30	30mm	1 1/4"	5 - 220	0.3 - 13.20	1.1 - 48.46
Connections Screwed - Pipe - Hose

 

Type	Pipe Size		L/min	m3/h	Gal/min
MM37	37mm	1 1/2"	7 - 350	0.42 - 21
MM50	50mm	2"	10 - 500	0.6 - 30
MM62	62mm	2 1/2"	20 - 800	1.2 - 48
MM75	75mm	3"	25 - 1300	1.5 - 78
MM100	100mm	4"	50 - 2200	3 - 132
MM150	150mm	6"	100 - 5000	6 - 300
MM200L	200mm	8"	300 - 5500	18 - 330
MM200	200mm	8"	300 - 8200	18 - 492
MM250	250mm	10"	400 - 13500	24 - 810
MM300	300mm	12"	500 - 20000	30 - 1200
Connections: Between Flanges

Low Viscosity Liquids - Pelton

Wide Flowrange Meters

Many flow lines are over-sized in relation to the maximum flow in order to reduce pressure losses in the system. The Litre Meter flowmeter offers a w ide range of operation and can function under these relatively low flow conditions. In cases of very low flow, the meter and its adjacent pipework can be a smaller size in order to enhance the accuracy. Naturally, the best accuracy lies in the top 90% of the meter's range.

Meters cover flows rates from 0.003 to 22,000 l/min. Each meter is calibrated over the standard flow rate range shown in the tables. For most meters at the higher figure, a pressure drop of 750 mbar is experienced across the meter. If a higher pressure drop can be accommodated, a flow rate over-run is permitted in most cases.

 

Viscosity Effects

Viscosity affects all turbine-type meters. If the viscosity is low, this is minimal. Viscosity imposes drag on the rotor, reducing the RPM even at high flows. Rangeability (turndown) is also reduced and it is desirable to operate in the higher end of the meter flowrange as non-linearity can appear at low flows.

A relatively high viscosity fluid can be metered if the application temperature and resulting viscosity is stable. This applies to many batching systems, for example, where simple re-calibration will restore system accuracy.

 

All viscous fluids create an increased pressure drop throughout pipeline systems. Since it is desirable to operate flowmeters at the higher end of their flow range, most users operate pumped rather than gravity fed systems.

 

Reliability Assured

Where flowmeters are correctly sized for the application, long life and high reliability is assured. An example of this is the measurement of diesel fuel at normal ambient temperatures as used in marine engines and land-based boilers. Flowmeters for this fluid have been operating for up to 30 years of continuous use without problems.

 

Environmental Protection

For most flowmeters IP68 is standard.

 

Flow Transmitters

Type Selection

Meter types fall into two basic categories. The first includes units designed for use with pressures up to 40 bar and temperatures up to 70°C. These meters have the transmitter electronics circuit housed in 316 stainless steel directly mounted above the turbine assembly on top of the meter body.

Meters in the second category are selected for a higher service pressure or for higher fluid temperatures. The top cap of the meter is constructed from stainless steel or titanium. The transmitter electronics is stalk- mounted in a metal enclosure. This design allows the temperature of the electronics to be maintained at less than 70°C while the metered fluid may be up to 135°C. Meters in this second category can be supplied for service up to 2000 bar.

 

Motor Type	Pressure Rating bar	Max Temp Centigrade	Body	Rotor	Turbine Ring	Transmitter Electronics or Top Cap
SPFA	40	70	SS	PFA	SS	SS
LMX	100	100	SS	PFA	SS	SS
SS	100	135	SS	PFA	SS	SS
SS	200	135	SS	PFA	SS	SS
SS	300+	135	SS	PFA	SS	SS
Ti	50	135	Ti	PFA	Ti	Ti
GN	2	70	GN	PFA	SS	SS
PVC	5	50	PVC	PFA	SS	SS
PVC3	5	50	PVC	PFA	PVC	PVC/SS

GN = Glass filled nylon	PP = Glass filled polypropylene
PVDF = Polyvinyladine flouride	PFA =Perfluoroalkoxy (Teflon)
PVC = Polyvinyl Chloride	SS =Stainless steel 316
TI = Titanium	* =Optionally to 85ßC
† = Optionally to 85ºC or 125ºC

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 are sealed and the rotor is constructed from PFA (perfluoroalkoxy) which has an effectively similar chemical resistance to PTFE (Teflon) for use to 135°C.

 

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, fluoropolymer and many others. Very high pressure meters can have metal O-Rings or C-rings.

The table above lists material combinations together with service pressure and temperature ratings.

 

Selected Materials

For Special Applications

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. Other materials such as super duplex and 17-4PH can be used.

 

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.