Baker Hughes Masoneilan 12400 Series, Instruction Manual & Safety Manual

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4.2.2. I
NTERNAL MOUNTING
An internally mounted 12400 Series instrument has no displacer chamber and the mechanism chamber bolts directly to the
vessel nozzle flange.
a. Type 12403 Top Flange Mounted Instrument (Figure 5)
There are two mounting possibilities:
1. Overhead space necessary for mounting the instrument is
sufficient:

Attach the displacer to the torque tube before bolting the
chamber flange to the nozzle flange on the vessel.
2. Overhead space is insufficient: in this case, install a detachable
hanger extension. Before attaching the extension:

Lower the displacer partway into the tank.

Fasten and pin the extension to the displacer.

Hook the displacer to the torque arm and lower the entire unit
into position. When the extension consists of several
detachable elements, repeat this operation for each element
and the lower the displacer progressively into the tank.

Mount the instrument and bolt the mechanism chamber onto
the nozzle flange.
b. Type 12404 side flange mounted Instrument (Figure 6)
When the instrument is side flange mounted, provide enough clearance to permit attachment of the displacer after the
chamber flange is bolted in place. To attach the displacer:

Reach into the end of the protective case and depress the torque arm.

Bring the displacer hanger up through the hole in the bottom of the case and slip the displacer hanger over the torque
arm pin.

Lower the displacer until the pin engages the top of the slot in the hanger.
4.2.2.1. Guide brackets for type 12404 (Figure 6)
If the liquid is in motion, provide brackets as shown in Figure 6 to guide the lower end of the displacer. The diameter of the
hole must be 25 to 35 mm (1” to 1 1/2”) larger than the diameter of the displacer for ranges to 1.8 m (6’ ), and 50 to 70 mm (2”
to 3”) larger for greater ranges.
Place t he brackets at 50 to 70 mm (2” to 3”) from each end of the displacer. Locate the centerline of the hole so that the
displacer hangs freely.
4.2.2.2. Stilling well for type 12403 (Figure 5)
If the liquid is turbulent, provide a stilling well.
Make the well from tubing or pipe of a suitable diameter to allow
sufficient clearance between displacer and pipe. Mount it so that
it extends at least 75 mm (3”) below a free hanging displacer.
Provide a hole at the top of the stilling well to equalize pressure
between well and vessel.
4.2.2.3. Instrument case mounting (Figure 7)
The standard case mounting is left handed — the case is to the left
of the displacer. Right hand mounting is optional. To reverse
instrument case mounting, refer to Section 9 - Maintenance.
Figure 5 Figure 6
Type 1240 3 Type 1240 4
Left mounting
(top view)
Right mounting
(top view)
Figure 7