Maintenance; Removal Of 12400 Case From Torque Tube; Installation Of 12400 Case On A Torque Tube; O N A 12200/300/400 Series Torque Tube - GE Masoneilan 12420 Instruction Manual & Safety Manual

9. Maintenance

1. Do not remove covers
manual 400152322. See figures 12 and 13.
2. The following actions may require opening the mechanism compartment. Before any new
commissioning, check that all covers and the plug are correctly mounted with gaskets/O-rings in good
condition.
3. Use only GE's Masoneilan original parts. Pay particular attention to the plug (90) which includes a
compressible gasket (192).
4. Read carefully instructions from the ATEX instruction Manual 400152322.
9.1. REMOVAL OF 12400 CASE FROM TORQUE TUBE (FIGURES 1, 12, 13, 15 & 21)
a. Switch off power supply. Unscrew safety screw (106) until it disengages from the case and remove the cover (104) of the
connection compartment. Disconnect supply wires from terminals (90).
b. Remove cover (107) of the mechanism compartment. Remove the spring arm (242) from the pin (243) on the beam to
disengage and relax it.
c. Using a 2.5 mm hex wrench, loosen screw (62) to uncouple the beam (54) from the torque rod.
d. While holding the case to prevent it from falling, loosen the four screws (121), using a 5 mm hex wrench, and remove
them along with the washers (122). Remove the case by pulling it along the axis of the torque tube while being careful to
prevent from any deformation of the coupling flexure (70).
e. If the original case or an identical one is reinstalled on the same torque tube, do not remove the coupling flange (116)
from the torque rod. Also, do not disconnect the coupling flexure subassembly (70). As an alternative, loosen screws (119)
using a 1.5 mm hex wrench and remove the coupling flange-flexure sub-assembly (116-70).
f. If the torque tube is not dedicated to 12400 instrument, remove the DLT case adapter kit, if necessary. This kit includes a
flange, a gasket, and screws, (see Figure 21).
9.2. INSTALLATION OF 12400 CASE ON A TORQUE TUBE (FIGURES 1, 12, 13, 15, 20 & 21)
9.2.1. O 12200/300/400 S
N A
a. Mount the torque tube (137) on a support. The knife pivot at the
back of the tube must be oriented toward the top.
b. On the transmission rod (138), mount the bias assembly (241).
c. On the transmission rod (138), mount the coupling S/A (75)
including flange (116), coupling flexure S/A (70) [incl. flexure (71), pin
(72) and washer (73)], flange (117) and its two loosened screws (118)
(see figure 19).
d. Attach a weight to the torque arm equivalent to that of a displacer
half immersed in a 1.4 specific gravity liquid. The target is the
coupling S/A and bias S/A to be vertical for mid S.G.1.4. See Section
7.1.b1.
e. Position the sub-assembly vertically on the rod so that the distance
between the coupling flexure (71) and the torque tube flange is 59.5
mm ±0.5 (see figure 20). Firmly tighten this sub-assembly to the rod,
using the two lateral screws (119).
f. Put the bias at 1 mm from the coupling S/A, align the bias S/A with
the coupling S/A and tighten it on the rod with the two lateral
screws (244).
48 | GE Oil & Gas
(281, 104 and 107) from 12400 case without prior reading of ATEX instruction
ERIES TORQUE TUBE
DANGER
® 2014 General Electric Company. All rights reserved.
54
62
241
119
244
243
116
70 / 71
118
59
Figure 20
Adjustment of Coupling Flexure t (71)
On Coupling Flange (116)
138
242