Emerson Rosemount 3308, Справочное руководство

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Reference Manual
00809-XXXX-4811, Rev AA
February 2012
A-3
Rosemount 3308
PRELIMINARY
Process Temperature and Pressure Rating
Process Temperature
Final rating depends on flange and O-ring
selection. Table A-1 on page A-4 gives
the temperature ranges for standard tank
seals with different O-ring materials.
Notes:
• The maximum product temperature is at the lower part of the flange
• The maximum temperature for the Remote Housing Connection at the vessel connection point is
302 °F(150 °C)
ASME / ANSI Flange Rating 316L SST Flanges according to ASME B16.5 Table 2-2.3. Max. 302 °F/580 psig (150 °C/40 bar)
EN Flange Rating 1.4404 according to EN 1092-1 material group 13E0. Max. 302 °F/580 psig (150 °C/40 bar)
Fisher & Masoneilan
Flange Rating 316L SST Flanges according to ASME B16.5 Table 2-2.3. Max. 302 °F/580 psig (150 °C/40 bar)
JIS Flange Rating 316L SST Flanges according to JIS B2220 material group 2.3. Max. 302 °F/580 psig (150 °C/40 bar)
Tri-Clamps Rating Maximum pressure is 16 bar for 1.5 in. (37.5 mm) and 2 in. (50 mm) housing; and 10 bar for 3 in. (75 mm)
and 4 in. (100 mm) housing. The final rating depends on the clamp and gasket.
Plate Design Certain models of flanged Alloy and PTFE covered probes have a tank connection design with a protective
flange plate of the same material as the probe and with a backing flange in 316L / EN 1.4404. The
protective flange plate prevents the backing flange from being exposed to the tank atmosphere
For Alloy C-276 and Alloy 400, probes with flange plate design is available up to Class 300/PN 40.
For PTFE, probes with flange plate design is available up to Class 150/PN 16
Flange Connection Rating See Table A-2 for the conditions used for flange strength calculations
Interface Measurements
Considerations The Rosemount 3308 is a good choice
for measuring the interface of oil and
water, or other liquids with significant
dielectric differences. It is also possible to
measure interfaces with a Rosemount
3308 in applications where the probe is
fully submerged in the liquid. If interface
is to be measured, follow these criteria:
• The dielectric constant of the upper
product must be known and should
not vary. The Radar Configuration
Tools software has a built-in dielectric
constant calculator to assist the user
in determining the dielectric constant
of the upper product
• The dielectric constant of the upper
product must have a lower dielectric
constant than the lower product to have a distinct reflection
• The difference between the dielectric constants for the two products must be larger than 10
• Max. dielectric constant for the upper product is 10 for the coaxial probe and 5 for twin lead probes
• The upper product thickness must be larger than 8 in. (0.2 m) for the flexible twin lead probe;
4 in. (0.1 m) for the rigid twin lead, and coaxial probes in order to distinguish the echoes of the two
liquids
• Sometimes there is an emulsion layer (mix of the products) between the two products which can affect
interface measurements. For guidelines on emulsion situations, consult your local Emerson Process
Management representative
Pressure
psig (bar)
Temperature °F (°C)
Max. Rating, Standard Tank Connections
580 (40)
232 (16)
-14 (-1)
-40 (-40) 302 (150)
PTFE covered probe
and flange (model
code 7)
Level
Interface Level
Level = Interface Level
Interface Measurement with
fully submerged probe
Interface Measurement