18.104.22.168 Mercury and mercury compounds. Clutches and parts shall not contain
mercury or mercury compounds and shall be free of mercury contamination. Use of
mercury shall be prohibited for inspection, examination, and tests.
22.214.171.124 Materials prohibited from lube oil contact. Paint, plastic, cadmium
and zinc coatings shall not be applied to any surface that will be in contact with
Metal surfaces shall be free of defects (see 4.6.1 through
3.2.4 Sur face hardened parts. Minimum case depth shall be in accordance
with 3.2, tables I and II, where applicable.
Castings shall pass the inspection specified in 4.5.4.
3.2.6 Recovered materials. Unless otherwise specified herein, all equip-
ment, material, and articles incorporated in the products covered by this specifi-
cation shall be new and may be fabricated using materials produced from recovered
materials to the maximum extent practicable without jeopardizing the intended use.
The term "recovered materials" means materials which have been collected or
recovered from solid waste and reprocessed to become a source of raw materials, as
opposed to virgin raw materials. None of the above shall be interpreted to mean
that the use of used or rebuilt products is allowed under this specification
unless otherwise specifically specified
3.2.7 Substitute materials. Materials other than those specified are
substitute materials (see 6.10 and 6.10.1).
3.3 General. Clutches shall be constructed for engagement, operation,
and disengagement without interruption under all specified expected conditions
of misalignment, shaft flexure, bearing wear, and any other specified anticipated
motion between the driving and driven shafts.
3.3.1 Operating characteristics. The design of all clutches shall be
matched with driver and driven equipment to provide stable operation under
all steady state, maneuvering, reverse, windmilling, locked shaft, trail shaft,
and disconnect operation (as applicable) conditions for propulsion clutches and
transient state load changes, including overloads for auxiliary clutches (see 6.3
and appendix A). Design shall also consider increased torque which occurs during
maneuvering and crash astern from full ahead, and then crash ahead to full power
for propulsion machinery. Time required for various operating conditions and
increased torque shall be in accordance with gear specification requirements or
parent equipment specifications when clutch requirements are contained therein, or
as required (see 6.2). Unless otherwise specified (see 6.2), the design torque
load of propulsion machinery clutches shall be 120 percent of full torque.
126.96.36.199 Natural frequencies. The natural frequency of a clutch design
shall not fall within 10 percent of the following:
(a) Any speed within the range from minimum to full power revolutions
per minute (r/rein) (see 6.2).
(b) Two times any speed within the same range as (a) above.