Lake Monitors Case Drain Monitor - Manual (Page 9)

The indicated flow reading will read high for heavier fluids and low for
lighter fluids. A corrective factor can be applied to the standard scale
or a special scale can be added at a slight additional costs. When
flowing other specific gravities, the basic equations below can be used.
For WATER Meters use: 1.0/Specific Gravity x scale reading
For OIL Meters use: .873/Specific Gravity x scale reading
Viscosity Effect
The meters incorporate a unique floating, sharp-edged orifice disk.
The floating, sharp-edged orifice disk offers greater operating stability
and accuracy over a wide range of viscosities.
PNEUMATIC METER USES & OPERATING THEORY
Lake’s rugged, high-pressure, pneumatic meters are designed for
permanent installation in compressed gas systems. These products
provide a low cost means to measure compressor volumetric outputs,
pneumatic tool consumptions and other industrial gas flow rates.
Lake meters operate using the variable annular orifice method with
compression spring return –the identical method used in our field
proven liquid flow rate meters. The product’s follower, where the
measurement is indicated, is magnetically coupled through a high
pressure casing to the meter’s internal orifice assembly.
Benefits of these design features are:
high operating pressure
linear displacement of the follower with respect to flow rate
high turn-down ratios
measuring accuracy within ±4% of full-scale
operation in any mounting orientation
Lake meters are offered in three standard materials of construction:
aluminum for standard monitoring applications to 600 PSIG
brass for media/material compatibility
stainless steel for compatibility and operation to 1000 PSIG.
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