249W Level Sensor
Instruction Manual
Form 5729
March 2005
8
Figure 11. Positioning Type 249W Wafer Body on
the Connecting Flange
W8224
LOCKING NUTS
DISPLACER SPUD
DISPLACER
STEM
EXTENSION
DISPLACER
STEM
END PIECE
DISPLACER ROD
COTTER SPRING
Figure 12. Displacer and Displacer Rod Connections
holes in the blind flange and connecting flange.
Thread the nut back onto the stud.
8. Tighten all nuts in a crisscross fashion to the
torque recommended in tables 1 or 2.
Maintenance
Sensor parts are subject to normal wear and must
be inspected and replaced as necessary. The
frequency of inspection and replacement depends
upon the severity of service conditions.
WARNING
Always wear protective clothing and
eyewear when performing any
maintenance operations to avoid
personal injury.
Avoid personal injury or property
damage resulting from the sudden
release of pressure. Before performing
any maintenance procedure:
D
Relieve any process pressure in
the process vessel where the Type
249W sensor is installed.
D
Drain the process liquid from the
process vessel.
D
Shut off any electrical or
pneumatic input to the controller or
transmitter attached to the Type 249W
sensor and vent any pneumatic supply
pressure.
D
Use caution when loosening
flange bolting or pipe plugs.
D
Remove the controller or
transmitter from the torque tube arm
(key 2).
Before performing any maintenance
procedure requiring the handling of
the displacer, inspect the displacer
(key 4) to make sure process pressure
or liquids have not penetrated the
displacer.
The displacer in this unit is a sealed
container. If penetrated by process
pressure or liquid, the displacer may
hold pressure or hazardous liquid for
an extended period. A displacer that
has been penetrated by process
pressure or liquid may contain:
D
pressure as a result of being in a
pressurized vessel.
D
liquid that becomes pressurized
due to a change in temperature.
D
liquid that is flammable,
hazardous, or corrosive.
Sudden release of pressure, contact
with hazardous liquid, fire, or
explosion, which might result in
personal injury or property damage,
can occur if a displacer that is
retaining pressure or process liquid is
punctured, subjected to heat, or
repaired.
