Section
7 Control and monitoring of main, auxiliary and emergency engines
7.1 General
7.1.2 Oil mist detection or engine bearing temperature monitors (or equivalent
device) fitted as required by Vol 2, Pt 2, Ch 1, 10.8 Oil mist detection 10.8.1
are to operate as follows:
- For trunk piston engines, automatic shutdown of the engine is to
occur when oil mist or high bearing temperature is detected.
- For crosshead engines, automatic slow-down is to occur when oil mist
or high bearing temperature is detected.
- Where arrangements are made to override the automatic slow-down or
shutdown due to high oil mist or bearing temperature, the override is to be
independent of other overrides.
- Where the bearing temperature monitoring method is chosen, all
bearings in the crankcase are to be monitored where practicable, e.g. main,
crankpin, crosshead.
- Where engine bearing temperature monitors or equivalent devices are
provided for the prevention of the build-up of oil mist that may lead to a
potentially explosive condition within the crankcase, details are to be submitted
for consideration. The submission is to demonstrate that the arrangements are
equivalent to those provided by oil mist detection, see
Vol 2, Pt 2, Ch 1, 10.8 Oil mist detection 10.8.15.
Where required, for each trunk piston engine, one oil mist detector (or engine bearing
temperature monitoring system or equivalent device) having two independent outputs for
initiating the alarm and shutdown would satisfy the requirement for independence between
alarm and shutdown systems.
7.1.3 All main and auxiliary engines intended for Mobility or Ship Type systems
are to be provided with means of indicating the lubricating oil pressure supply to them.
Where such engines are of more than 37 kW, audible and visual alarms are to be fitted to
give warning of an appreciable reduction in pressure of the lubricating oil supply.
Further, these alarms are to be actuated from the outlet side of any restrictions, such
as filters, coolers, etc.
7.2 Main engine governors
7.2.1 An efficient speed governor is to be fitted to each main engine so adjusted
that the speed does not exceed that for which the engine is to be certified by more
than 15 per cent.
7.2.2 Engines coupled to electrical generators that are the source of power for
main electric propulsion are to comply with the requirements for electrical generator
engines in respect of governors and overspeed protection devices.
7.2.3 When electronic speed governors of main internal combustion engines form part of a
remote control system, they are to comply with the following conditions:
- If lack of power to the governor may cause changes in the present speed
and direction of thrust of the propeller, which consequently compromise safe
operation of the vessel, then a backup power supply is to be provided;
- Local control of the engines is always to be possible. A means
to effect safe transfer of control to the local control position and then control the
engine is to be available in all normal and reasonably foreseeable abnormal
conditions;
- In addition, electronic speed governors and their actuators are
to be type approved in accordance with LR’s Type Approval System Test Specification
Number 1.
7.3 Auxiliary and emergency engine governors
7.3.1 Prime movers for driving generators of the main and emergency sources of electrical
power are to be fitted with a speed governor which will prevent transient frequency
variations in the electrical network in excess of ±10 per cent of the rated frequency,
with a recovery time to steady state conditions not exceeding 5 seconds, when the
maximum electrical step load is switched on or off.
7.3.2 In the case when a step load equivalent to the rated output of a generator
is switched off, a transient speed variation in excess of 10 per cent of the rated speed
may be acceptable, provided that this does not cause the intervention of the overspeed
device as required by Vol 2, Pt 2, Ch 1, 7.5 Overspeed protective devices.
7.3.3 At all loads between no load and rated power, the permanent speed variation should not
be more than ±5 per cent of the rated speed.
7.3.4 Prime movers are to be selected in such a way that they will meet the load demand within
the ship’s power distribution system. Application of electrical load should be possible
with two load steps and must be such that prime movers, running at no load, can suddenly
be loaded to 50 per cent of the rated power of the generator followed by the remaining
50 per cent after an interval sufficient to restore the speed to steady state. Steady
state conditions should be achieved in not more than 5 seconds. Steady state conditions
are those at which the envelope of speed variation does not exceed +1 per cent of the
declared speed at the new power.
7.3.5 Application of electrical load in more than two load steps can only be
permitted if the conditions within the ship’s power distribution system permit the use
of such prime movers which can only be loaded in more than two load steps ( see
Figure 1.7.1 Reference values for maximum possible sudden power increase (four-stroke
engines)) and provided that this is already
allowed for at the design stage. This is to be verified in the form of system
specifications to be approved and to be demonstrated at ship’s trials. In this case, due
consideration is to be given to:
- The power required for the electrical equipment to be
automatically switched on after blackout and to the sequence in which it is
connected.
- Where generators are to be operated in parallel and where the
power has to be transferred from one generator to another in the event of any one
generator being switched off.
Figure 1.7.1 Reference values for maximum possible sudden power increase (four-stroke
engines)
7.3.6 Emergency generator sets are to comply with the requirements of Vol 2, Pt 2, Ch 1, 7.3 Auxiliary and emergency engine governors 7.3.1 to Vol 2, Pt 2, Ch 1, 7.3 Auxiliary and emergency engine governors 7.3.3 even when:
- their total consumer load is applied suddenly; or
- their total consumer load is applied in steps, subject to:
- the total load being supplied within 45 seconds of
power failure on the main switchboard;
- the maximum step load being declared and
demonstrated;
- the power distribution system being designed such that
the declared maximum step loading is not exceeded; and
- the compliance of time delays and loading sequence with
the above being demonstrated at ship’s trials.
7.3.7 For a.c. generating sets operating in parallel, the governing
characteristics of the prime movers shall be such that within the limits of 20 per cent
and 100 per cent total load, the load on any generating set will not normally differ
from its proportionate share of the total load by more than 15 per cent of the rated
power of the largest machine, or 25 per cent of the rated power of the individual
machine in question, whichever is the less. For an a.c. generating set intended to
operate in parallel, facilities are to be provided to adjust the governor sufficiently
finely to permit an adjustment of load not exceeding 5 per cent of the rated load at
normal frequency.
7.4 Additional requirements for auxiliary engine governors for naval vessels
7.4.1 The no-load stability of governors on electrical generator engines is to
be such as to enable satisfactory paralleling to be achieved.
7.5 Overspeed protective devices
7.5.1 Each main engine developing 220 kW or over which can be declutched or which
drives a controllable pitch propeller and also each auxiliary engine developing 220 kW
and over for driving an electric generator, is to be fitted with an approved overspeed
protective device.
7.6 Unattended machinery
7.6.1 Where main and auxiliary engines are fitted with automatic or remote
controls so that under normal operating conditions they do not require any manual
intervention by the operators, they are to be provided with the alarms and safety
arrangements required by Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery to Vol 2, Pt 2, Ch 1, 7.8 Auxiliary engines as appropriate.
Alternative arrangements which provide equivalent safeguards will be considered.
7.6.2 Where machinery is arranged to start automatically or from a remote control station,
interlocks are to be provided to prevent start-up under conditions which could present a
hazard to the machinery.
7.6.3 Where machinery specified in this Section is required to be provided with a
standby pump, the standby pump is to start automatically if the discharge pressure from
the working pumps falls below a predetermined value.
7.6.4 Where a first stage alarm together with a second stage alarm and automatic
shutdown of machinery are required in the relevant Tables of this Section, the sensors
and circuits utilised for the second stage alarm and automatic shutdown are to be
independent of those required for the first stage alarm.
7.6.5 Means are to be provided to prevent leaks from high pressure fuel oil
injection piping for main and auxiliary engines dripping or spraying onto hot surfaces
or into machinery air inlets. Such leakage is to be collected and, where practicable,
led to a collector tank(s) fitted in a safe position. An alarm is to be provided to
indicate that leakage is taking place. These requirements may also be applicable to high
pressure hydraulic oil piping depending upon the location.
7.7 Engines for propulsion purposes
7.7.1 Alarms and safeguards are indicated in Vol 2, Pt 2, Ch 1, 7.7 Engines for propulsion purposes 7.7.2 to Vol 2, Pt 2, Ch 1, 7.7 Engines for propulsion purposes 7.7.8 and Table 1.7.1 Engines for propulsion purposes:
Alarms and slow-downs and Table 1.7.2 Engines for propulsion purposes:
Automatic shutdowns.
Table 1.7.1 Engines for propulsion purposes:
Alarms and slow-downs
| Item
|
Alarm
|
Note
|
| Lubricating oil sump level
|
Low
|
Engines
|
| Lubricating oil inlet pressure*
|
1st
stage
low
|
Engines. Slow-down
|
| Lubricating oil inlet
temperature*
|
High
|
Engines
|
| Lubricating oil filters differential
pressure
|
High
|
—
|
| Activation of oil mist detection
arrangements (or activation of the temperature monitoring systems or
equivalent devices of:
- the engine main, crank and crosshead bearing oil
outlet; or
- the engine main, crank and crosshead bearing)
|
High
|
For crosshead engines, automatic slow-down. For trunk-piston engines,
see
Table 1.7.2 Engines for propulsion purposes:
Automatic shutdowns. See also
Vol 2, Pt 2, Ch 1, 7.1 General 7.1.2
|
| Cylinder lubricator flow
|
Low
|
One sensor per lubricator unit on
crosshead engines. Slow-down
|
| Thrust bearing temperature*
|
High
|
Slow-down
|
| Piston coolant inlet pressure
|
Low
|
If a separate system.
Slow-down
|
| Piston coolant outlet
temperature*
|
High
|
Per cylinder (if a separate system).
Slow-down
|
| Piston coolant outlet flow*
|
Low
|
Per cylinder (if a separate system).
Slow-down
|
| Cylinder coolant inlet pressure or
flow*
|
Low
|
Slow-down (automatic on trunk piston
engines)
|
| Cylinder coolant outlet
temperature*
|
1st
stage high
|
Per cylinder (if a separate system)
Slow-down (automatic on trunk piston)
|
| Engine cooling water system – oil
content
|
High
|
Required for crosshead engines where
engine cooling water used in oil/water heat exchangers
|
| Sea-water cooling pressure
|
Low
|
—
|
| Fuel valve coolant pressure
|
Low
|
If a separate system
|
| Fuel valve coolant temperature
|
High
|
If a separate system
|
| Fuel oil pressure from booster
pump
|
Low
|
—
|
| Fuel oil temperature or
viscosity*
|
High
and Low
|
Heavy oil only
|
| Common rail fuel oil
pressure
|
Low
|
—
|
| Fuel oil high pressure
piping*
|
Leakage
|
See
Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery 7.6.5
|
| Common rail servo oil pressure
|
Low
|
—
|
| Charge air cooler outlet
temperature
|
High
|
Trunk piston engines
|
| Scavenge air temperature
(fire)
|
High
|
Per cylinder, (2 stroke engines).
Slow-down
|
| Scavenge air receiver water level
|
High
|
—
|
| Exhaust gas temperature*
|
High
|
Per cylinder. Slow-down (automatic on trunk
piston engines), see Note 5
|
| Exhaust gas temperature deviation from
average*
|
High
|
Per cylinder, for engine power >500
kW/cylinder, see Note 5
|
| Turbocharger speed
|
High
|
Category B and C turbochargers, see Notes
11 and 12
|
| Turbocharger exhaust gas inlet
temperature
|
High
|
Category B and C turbochargers, see Notes
6 and 12
|
| Turbocharger lubricating oil inlet
pressure
|
Low
|
Only for forced lubrication systems on category B
and C turbochargers, see Notes 7, 10 and 12
|
| Turbocharger lubricating oil outlet
temperature
|
High
|
Category C turbochargers, if not a forced system, oil
temperature near each bearing, see Notes 7 and 12
|
| Starting air pressure*
|
Low
|
Before engine manoeuvring valve
|
| Control air pressure
|
Low
|
—
|
| Direction of rotation
|
Wrong way
|
Reversible engines, see also
Vol 2, Pt 2, Ch 1, 7.7 Engines for propulsion purposes 7.7.7
|
| Automatic start of engine
|
Failure
|
See
Vol 2, Pt 2, Ch 1, 7.7 Engines for propulsion purposes 7.7.7
|
| Electrical starting battery charge
level*
|
Low
|
—
|
| Feed water or
water/thermal fluid forced circulation flow (if fitted )
|
Low
|
See
Vol 2, Pt 7, Ch 3, 6.2 Feed and circulation pumps 6.2.6 and Note 8
|
| Uptake temperature
|
High
|
To monitor for soot fires. See Notes 8
and 9
|
Note
1. Where 'per cylinder' appears in this
Table, suitable alarms may be situated on manifold outlets for trunk
piston engines.
|
Note
2. For engines and gearing of 1500 kW or
less only the items marked * are required.
|
Note
3. Common sensors are acceptable for
alarms and slow-down functions.
|
Note
4. Except where stated otherwise in the
Table, slow-down may be effected by either manual or automatic means,
by reduction of speed or power as appropriate.
|
Note
5. For trunk piston engine powers <500
kW/cylinder, a common sensor for exhaust gas manifold temperature may
be fitted.
|
|
Note 6. Alarm and indication
of the exhaust gas temperature at turbocharger inlet may be waived if
alarm and indication for individual exhaust gas temperature is provided
for each cylinder and the alarm level is set to a value specified by the
turbocharger manufacturer. For Category B turbochargers, the exhaust gas
temperature may be alternatively monitored at the turbocharger outlet
provided that the correlation between inlet and outlet temperatures is
established and verified and the alarm level is set to a correspondingly
safe level for the turbine.
|
Note
7. Where the outlet temperature for each
bearing cannot be measured due to the design, details of alternative
proposals in accordance with the turbocharger manufacturer’s
instructions may be submitted for consideration.
|
Note
8. Alarm only required when an exhaust
gas economiser/boiler/thermal oil heater is fitted.
|
Note
9. Alternatively, details of an
appropriate fire detection system are to be submitted for
consideration.
|
|
Note 10. Separate sensors are to be provided if the lubrication oil system
of the turbocharger is not integrated with the lubrication oil system of
the engine or if it is separated by a throttle or pressure reduction
valve from the engine lubrication oil system. Where the turbocharger is
provided with a self-contained lubricating oil system integrated with the
turbocharger, lubricating oil inlet pressure need not be
monitored.
|
Note
11. Where multiple turbochargers are
activated sequentially, speed monitoring is not required for the
turbocharger(s) being activated last in the sequence, provided that
all turbochargers share the same intake air filter and they are not
fitted with waste gates.
|
|
|
Table 1.7.2 Engines for propulsion purposes:
Automatic shutdowns
| Item
|
Alarm
|
Note
|
| Lubricant oil inlet pressure
|
2nd stage low
|
Automatic shutdown of engines,
see
Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery 7.6.4
|
| Activation of oil mist detection
arrangements (or activation of the temperature monitoring systems or
equivalent devices of:
- the engine main and crank bearing oil outlet; or
- the engine main and crank bearing)
|
High
|
For trunk piston engines, automatic
shutdown. For crosshead engines, see
Table 1.7.1 Engines for propulsion purposes:
Alarms and slow-downs. See also
Vol 2, Pt 2, Ch 1, 7.1 General 7.1.2.
|
| Cylinder coolant outlet
temperature
|
2nd stage high
|
Automatic shutdown of trunk piston,
see
Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery 7.6.4
|
| Overspeed
|
High
|
Automatic shutdown of engine,
see also
Vol 2, Pt 2, Ch 1, 7.5 Overspeed protective devices. Details of alternative proposals in accordance with
the manufacturer’s instructions may be submitted for consideration
|
7.7.4 The
following engine services are to be fitted with automatic temperature
controls so as to maintain steady state conditions throughout the
normal operating range of the propulsion engine(s):
-
Lubricating oil
supply.
-
Piston coolant
supply, where applicable.
-
Cylinder coolant
supply, where applicable.
-
Fuel valve coolant
supply, where applicable.
-
Fuel oil supply,
where fuel oil grades require heating or cooling only, see also
Vol 2, Pt 2, Ch 1, 7.7 Engines for propulsion purposes 7.7.5.
7.7.6 Indication
of the starting air pressure is to be provided at each control station
from which it is possible to start the main propulsion engine(s).
7.7.7 The number of automatic consecutive attempts which fail to produce a start
are to be limited to three. For reversible engines which are started and stopped for
manoeuvring purposes, means are to be provided to maintain sufficient starting air in
the air receivers. For electric starting, see
Vol 2, Pt 2, Ch 1, 9.2 Electric starting.
7.7.8 Prolonged
running in a restricted speed range is to be prevented automatically
or, alternatively, an indication of restricted speed ranges is to
be provided at each control station.
7.8 Auxiliary engines
7.8.2 For engines operating on heavy fuel oil, automatic temperature or viscosity
controls are to be provided.
Table 1.7.3 Auxiliary engines: Alarms and
shutdowns
| Item
|
Alarm
|
Note
|
| Lubricating oil inlet temperature
|
High
|
—
|
| Lubricating oil inlet pressure
|
1st stage low
|
—
|
|
|
2nd stage low
|
Automatic shutdown of engine,
see
Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery 7.6.4
|
| Activation of oil mist detection arrangements (or activation of the
temperature monitoring systems or equivalent devices of:
- the engine
main and crank bearing oil outlet; or
- the engine main and crank
bearing)
|
High
|
Automatic shutdown of engine, see
also
Vol 2, Pt 2, Ch 1, 7.1 General 7.1.2
|
| Fuel oil
high pressure piping
|
Leakage
|
See
Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery 7.6.5
|
| Coolant
outlet temperature (for engines >220 kW)
|
1st stage high
|
—
|
|
|
2nd stage high
|
Automatic shutdown of engine,
see
Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery 7.6.5
|
| Coolant
pressure or flow
|
Low
|
—
|
| Fuel oil
temperature or viscosity
|
High and Low
|
Heavy oil only
|
| Overspeed
|
High
|
Automatic shutdown of engine, see
also
Vol 2, Pt 2, Ch 1, 7.5 Overspeed protective devices. Details of alternative proposals in accordance with
the manufacturer’s instructions may be submitted for consideration.
|
| Common rail servo oil pressure
|
Low
|
—
|
| Common rail fuel oil pressure
|
Low
|
—
|
| Starting
air pressure
|
Low
|
—
|
| Electrical starting battery charge level
|
Low
|
—
|
| Exhaust
gas temperature (for engines >500 kW/cylinder)
|
High
|
Per cylinder.
|
| Feed water or water/thermal fluid forced circulation flow (if
fitted)
|
Low
|
See
Vol 2, Pt 7, Ch 3, 6.2 Feed and circulation pumps 6.2.6 and Note 3
|
| Uptake temperature
|
High
|
To monitor for soot
fires. See Notes 3 and 4
|
| Turbocharger speed
|
High
|
Category B and C
turbochargers, see Notes 7 and 9
|
| Turbocharger exhaust gas inlet temperature
|
High
|
Category B and C
turbochargers, see Notes 8 and 9
|
| Turbocharger lubricating oil outlet temperature
|
High
|
Category C
turbochargers, if not a forced system, oil temperature near each bearing,
see Notes 6 and 9
|
| Turbocharger lubrication oil inlet pressure
|
Low
|
Only for forced
lubrication systems on category B and C turbochargers, see Notes 5, 6
and 9
|
Note
2. The tailoring document or System
Design Description may specify additional requirements of the Naval
Administration.
Note
3. Alarm only required when an exhaust
gas economiser/boiler/thermal oil heater is fitted.
Note
4. Alternatively, details of an
appropriate fire detection system are to be submitted for
consideration.
Note 5. Separate sensors are
to be provided if the lubrication oil system of the turbocharger is not
integrated with the lubrication oil system of the engine or if it is
separated by a throttle or pressure-reduction valve from the engine
lubrication oil system.
Note 6. Where outlet
temperature from each bearing cannot be monitored due to the
engine/turbocharger design, alternative arrangements may be accepted.
Continuous monitoring of inlet pressure and inlet temperature in
combination with specific intervals for bearing inspection in accordance
with the turbocharger manufacturer’s instructions may be accepted as an
alternative.
Note 7. Where multiple turbochargers are activated sequentially, speed
monitoring is not required for the turbocharger(s) being activated last
in the sequence, provided that all turbochargers share the same intake
air filter and they are not fitted with waste gates.
Note 8. Alarm and indication of the exhaust gas temperature at the
turbocharger inlet is not required if alarm and indication for individual
exhaust gas temperature are provided for each cylinder and the alarm
level is set to a value specified by the turbocharger manufacturer. For
Category B turbochargers, the exhaust gas temperature may be
alternatively monitored at the turbocharger outlet provided that
correlation between inlet and outlet temperatures is established and
verified and the alarm level is set to a correspondingly safe level for
the turbine.
|
7.9 Emergency engines
7.9.1 Alarms and safeguards are indicated in Table 1.7.4 Alarms and safeguards for
emergency engines.
Table 1.7.4 Alarms and safeguards for
emergency engines
|
Item
|
Alarm for engine power <220 kW
|
Alarm for engine power ≥220 kW
|
Note
|
| Fuel oil
leakage from pressure pipes
|
Leakage
|
Leakage
|
See
Vol 2, Pt 2, Ch 1, 7.6 Unattended machinery 7.6.5
|
| Lubricating oil temperature
|
-
|
High
|
-
|
| Lubricating oil pressure
|
Low
|
Low
|
-
|
| Activation of oil mist detection arrangements (or activation of the
temperature monitoring systems or equivalent devices of:
-
the engine main and crank bearing oil outlet; or
- the
engine main and crank bearing)
|
-
|
High
|
See Note
|
| Coolant
pressure or flow
|
-
|
Low
|
-
|
| Coolant
Temperature (can be air)
|
High
|
High
|
-
|
| Overspeed
|
-
|
High
|
Automatic
shutdown
|
|
Note For engines having a
power of more than 2250 kW or a cylinder bore of more than 300 mm.
|
7.9.2 The
safety and alarm systems are to be designed to 'fail safe'. The characteristics
of the 'fail safe' operation are to be evaluated on the basis not
only of the system and its associated machinery, but also the complete
installation, as well as the ship.
7.9.3 Regardless
of the engine output, if shutdowns additional to those specified in Table 1.7.4 Alarms and safeguards for
emergency engines are provided except
for the overspeed shutdown, they are to be automatically overridden
when the engine is in automatic or remote control mode during navigation.
7.9.5 In
addition to the fuel oil control from outside the space, a readily
accessible local means of engine shutdown is to be provided.
7.10 Additional requirements for engine stopping
for naval vessels
7.10.1 At least
two independent means of stopping the engines quickly from the control
station under any conditions are to be available.
|