ARMY TM 9-6115-604-12
NAVY NAVFAC P-8-633-12
(4) Install right and left hand upper rear stiffeners (5 and 6, Figure 4-12), the #7-#11 top roof panel (7), the #12 top
roof panel (4), gaskets (8), gasket (12, Figure 4-13), and roof angles (4 through 8) using hexagon head cap
screws, hexagonal nuts, and lock washers (1, 2, and 3, Figure 4-12), and screw and captive washer assemblies
(1, Figure 4-13).
(5) Install hexagon head cap screws (16, Figure 4-13), lock washers (17), and hexagonal nuts (18), securing roof
angles (4 through 8).
(6) Install hexagon head cap screws (16, Figure 4-13), flat washers (18), lock washers (17), and hexagonal nuts (19),
and install conduit support assembly (13).
(7) Install hexagon head cap screws (16), lock washers (17), flat washers (18), and hexagonal nuts (19), and install
support brackets (15) and conduit support hanger (14).
(8) Install mufflers In accordance with paragraph 3-15.
4-18. MAINTENANCE OF SOUND INSULATION PANELS. See Figure 4-13. Interior roof and wall panels of the
control room are lined with sound insulation material comprised of acoustic dampers and absorbers. To minimize
transmission of engine noise and vibration into the control room and switchgear compartments, the rear control cabinet
panels and supporting hardware are likewise acoustically insulated with acoustic barriers, absorbers, and dampers Repair
of sound insulation panels generally consists of patching minor tears and holes on the exterior fabric lining or
replacement of sound insulation layers where damage or deterioration is evident.
Repair. Repair minor tears and holes on the grey fabric lining by patching over with fabric mending tape.
Replace. Replacement of sound insulation layers consists of removal of all components mounted on the affected
housing panel, removal and replacement of sound insulation material on housing panels, and reinstallation of
components and panels. It is recommended that replacement sound insulation layers be precut to proper
dimensions prior to installation.
Determine area requiring sound insulation replacement Remove all mounted assemblies or components from
affected panel(s) as needed If electrical components require removal, tag and disconnect all wiring connections
prior to removal.
For removal of AC components such as distribution panels, 120 V ac receptacles, junction boxes, control
room heater, light fixtures and switches, refer to the appropriate paragraphs In Section IX of this Chapter (b)
For removal of fan and motor assembly B1 03, fire extinguisher brackets, fan shutter assembly, desk top, and
document component, refer to paragraph 4-12 of this section.
Remove housing panels requiring sound insulation replacement.
To remove roof panels, refer to paragraph 4-13, step a, and Figure 4-12 and Figure 4-14. Note that only the
first three roof panels (4 and 7, Figure 4-12) directly above the control room are acoustically insulated.
To remove control room panels requiring sound insulation replacement, refer to paragraph 4-13 and Figure 4-
To remove engine/generator compartment sound insulations (at rear of switchgear cabinets only), refer to step
Roof Panel Insulation Replacement.
Remove roof angles (4 and 5, Figure 4-13) from #12 roof panel (4, Figure 4-12) by removing screw and
captive washer assemblies (1, Figure 4-13) at both panel ends. Remove roof strips (2 and 3, Figure 4-13) and
roof angles (6, 7, and 8) from #10 and #11 roof panels by removing screw and captive washer assemblies (1)
at panel comers.