Instruction Manual
D200099X012
249 Caged Sensors
April 2017
11
Figure 7. Cage Head Mounting Positions
RIGHT‐HAND MOUNTING
LEFT‐HAND MOUNTING
67FR FILTER/REGULATOR
AH9150-A
A2613-2
1. Before starting any maintenance procedure, be sure the following safety actions have been completed.
Relieve process pressure in the vessel where the 249 sensor is installed.
Drain the process liquid from the vessel.
Shut off any electrical or pneumatic input to the controller or transmitter attached to the 249 sensor and vent
any pneumatic supply pressure. Remove the controller or transmitter from the torque tube arm.
Be sure the cage is also free of process pressure and/or liquid. Use caution when loosening flange bolting or pipe
plugs.
Be sure process pressure or liquids have not penetrated the displacer.
2. Remove the hex nuts (keys 20 or 22) from the bolting (key 21) and reposition the head as desired.
Replacing the Torque Tube Arm and Changing the Mounting
1. Looseness of the driver bearing (key 4); wear on its knife‐edged surface; or a bent, worn, or corroded displacer rod
assembly (key 7) may impair performance. Be especially sure to check the ball on the displacer rod.
2. After following the proper procedure to remove the cage head and the displacer from the cage, move the sensor
assembly to a suitable maintenance area.
CAUTION
Support the sensor assembly to avoid damage to the displacer, displacer stem, displacer rod assembly, and associated
parts.
3. Remove the controller/transmitter and displacer (key 10). Then, remove the hex nuts (key 20) that hold the torque
tube arm (key 3) to the cage head (key 2). Separate the torque tube arm from the cage head.
