Instruction Manual

Instruction Manual

D102803X012

249W Sensor

December 2012

Figure 13. Torque Tube and Displacer Rod Assemblies

W0654‐1

REMOVAL OR INSTALLATION OF POSITIONING PLATE

EXPLODED VIEW OF TORQUE TUBE AND DISPLACER ROD ASSEMBLY

DISPLACER ROD

ASSEMBLY

ROTARY

SHAFT

TORQUE TUBE

OUTER TUBE END

POSITIONING PLATE

DRIVER BEARING

W0145‐2

GASKET

1. After following the proper procedure to remove the sensor and the displacer from the process vessel or displacer

cage, move the sensor assembly to a suitable maintenance area. Support the assembly to avoid damage to the

displacer, displacer stem, displacer rod assembly, and associated parts.

2. Remove the controller/transmitter and displacer (key 4). Then, remove the hex nuts (key 20) that hold the torque

tube arm (key 2) to the wafer body (key 1). Separate the torque tube arm from the wafer body.

3. Remove the nuts (key 18) and retaining flange (key 14) holding the positioning plate (key 15) at the end of the

torque tube arm.

CAUTION

If the displacer is still attached to the displacer rod at this point, be careful not to let the torque tube assembly slip when

using the screwdriver leverage procedure in steps 4 and 6. Sudden release of the displacer could cause damage to the

displacer or torque tube assembly.

4. Remove the positioning plate (key 15) by freeing its two lugs.

The vertical lug fits into a hole in the flange of the torque tube arm (figure 13). The horizontal lug (hidden behind

the screwdriver in figure 13) fits into a slot in the outer tube end of the torque tube assembly (the figure 13

exploded view shows this lug to the right of the outer tube end).

The positioning plate may be pried away from the torque tube arm and outer tube end if the displacer already has

been disconnected from the displacer rod. However, if the displacer is still connected to the displacer rod, place a

screwdriver blade in the slots of the positioning plate and outer tube end as shown in figure 13. Slowly turn the

positioning plate to release its lug from the torque tube arm. Then, carefully turn the plate back to allow the

displacer to come to rest and slip the other lug of the plate from its slot in the outer tube end.

5. Pull the torque tube assembly and tube end gasket out of the torque tube arm. Remove the tube end gasket

(key 13) and discard (a new gasket will be installed in step 6). Clean and inspect the gasket mating surfaces.

6. Install a new tube end gasket into recess in torque tube arm.

7. Insert the torque tube assembly into the torque tube arm as shown in figure 13. Rotate the torque tube assembly

until its socket mates with the driver member on the displacer rod assembly and so the outer tube flange rests