 |
|||
|
|
|||
| ||||||||||
|
|  MIL-E-23457B(SHIPS)
other accessories or engine attached piping necessary for engine operation but which are not
specified herein or in the contract or order shall be furnished by the engine manufacturer.
Unless otherwise specified in the contract or order, piping including valve fittings and
flanges, alarm systems, wiring, or mechanical linkage required to connect detached acces-
sories, instruments, and controls to the engine, or to cooling water, fuel starting air,
electrical, exhaust, or lubrication system will be furnished by the installing activity.
3.7.2 Guards and shields. Guards and shields shall be furnished as specified in
#
3.7.2.1 and 3.7.2.2
3.7.2.1 Gaurds. Guards for protection of personnel shall be provided for flywheels
#
and other exposed parts. Where there are no feasible means for attaching the guard
to the equipment, the guards will be furnished by the engine manufacturer and the installing
activity will accomplish the installation.
3.7.2.2 Shields. Hot machinery surfaces shall be shielded or insulated so that no
#
external surface of the machinery shall exceed a temperature of 204.4C. Asbestos insulating
products or materials shall not be used. Fuel and lubricating oil filters, strainer, lines
or fittings, including gage lines, shall be located or shielded so that any leaks cannot
drip or spray on any component with a surface temperature of 400F or higher or into the
engine intake.
3.7.3 Turbochargers.
Turbochargers (if used) shall be capable of containing within
#
the housing any parts of the rotating members which may become fragmented due to loosening,
shattering, or over-speeding. The engine manufacturer shall confirm to the DCAS that this
requirement is met by actual destructive testing or certified documented proof of prior
testing.
If this requirement cannot be met, the installing activity should be advised so
that protective shielding can be installed.
#
3.7.4 Crackcase fumes. The engine manufacturer shall provide a system to dissipate
through the engine intake or exhaust system all oil fumes generated by the engine in the
crankcase and other areas.
3.7.5 Engine crankcase and air box explosion protective devices or design Diesel
#
engines with cylinder bore diameter of 6 inches or greater shall be protected from the hazard
of crankcase or air receiver explosions by one of the procedures specified in 3.7.5.1 through
3.7.5.5.
3.7.5.1 If the crankcase can be demonstrated by test (see 4.4.2.10) to withstand an
#
internal gas gage pressure of 125 pounds per square inch (lb/in 2 ) without rupture, it shall
be considered to be safe to contain a crankcase explosion and no other protection devices
are required. For the purpose of this demonstration, the term crankcase shall be interpreted
to include the entire engine structure that would be exposed to internal gas pressure in the
event of a crankcase explosion.
#
3.7.5.2 If the integrity of the engine crankcase and related volume cannot be demon-
strated as specified in 3.7.5.1, the engine shall be provided with spring loaded explosion
relief valves, to provide a total relief area of at least 1-1/2 square inches (in2) for each
cubic foot (ft 3 ) of total crankcase volume. These relief valves shall be fully open at a
crankcase gage pressure of 20 lb/in2, and to close and seal the crankcase from air when the
pressure has been relieved. The entire crankcase system in the terms of 3.7.5.1, including
any access covers, shall withstand an internal gage pressure of at least 25 lb/in2 without
failure when explosion protection devices are used.
#
3.7.5.3 The air receivers of two cycle engines (only) of 6 inch diameter or larger
cylinder sizes shall also be protected from air receiver explosions. If the air receivers,
including all associated structure that would be subject to gas pressure in event of air
explosion can be demonstrated by test (see 4.4.2.11) to withstand an internal gas gage
pressure of 125 lb/in2, no other air receiver explosion protection device shall be required.
#
3.7.5.4 If the pressure integrity requirements of 3.7.5.3 cannot be met, the air
receiver shall be provided with an explosion relief valve or valves, having at least
1-1/2 in2 of relief area per ft3 of total air receiver system volume. These relief valves
shall be tight at maximum air receiver operating pressure and to be fully open at a
gage pressure of 20 lb/in2 above that operating pressure level. The valves shall be capable
of relieving the explosion and reseating tightly. When these explosion relief valves are
8
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals