Man L23/30DF, Руководство по проекту

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The ash must be soft. If this prerequisite is not met, it is likely the rate of dep-
osition in the combustion chamber will be higher, particularly at the outlet
valves and at the turbocharger inlet housing. Hard additive ash promotes pit-
ting of the valve seats, and causes valve burn-out, it also increases mechani-
cal wear of the cylinder liners.
Additives must not increase the rate, at which the filter elements in the active
or used condition are blocked.
The washing ability must be high enough to prevent the accumulation of tar
and coke residue as a result of fuel combustion.
The selected dispersibility must be such that commercially-available lubricat-
ing oil cleaning systems can remove harmful contaminants from the oil used,
i.e. the oil must possess good filtering properties and separability.
The neutralisation capability (ASTM D2896) must be high enough to neutral-
ise the acidic products produced during combustion. The reaction time of
the additive must be harmonised with the process in the combustion cham-
ber.
The evaporation tendency must be as low as possible as otherwise the oil
consumption will be adversely affected.
The lubricating oil must not contain viscosity index improver. Fresh oil must
not contain water or other contaminants.
Lubricating oil selection
Engine SAE class
16/24, 21/31, 27/38, 28/32S, 32/40, 32/44, 35/44DF, 40/54,
45/60, 48/60, 58/64, 51/60DF
40
Table 2: Viscosity (SAE class) of lubricating oils
We recommend doped lube oils (HD oils) according to the international spec-
ification MIL-L 2104 or API-CD with a base number of BN 10–16 mg KOH/g.
Lube oils of military specification O-278 may be used if they are listed in the
table Lube oils approved for use in MAN Diesel & Turbo four-stroke engines
that run on gas oil and diesel fuel . Lube oils not listed here may only be used
after consultation with MAN Diesel & Turbo.
The operating conditions of the engine and the quality of the fuel determine
the additive content the lube oil should contain. If marine diesel oil is used,
which has a high sulphur content of 1.5 up to 2.0 weight %, a base number
(BN) of appr. 20 should be selected. However, the operating results that
ensure the most efficient engine operation ultimately determine the additive
content.
In engines with separate cylinder lubrication systems, the pistons and cylin-
der liners are supplied with lubricating oil via a separate lubricating oil pump.
The quantity of lubricating oil is set at the factory according to the quality of
the fuel to be used and the anticipated operating conditions.
Use a lubricating oil for the cylinder and lubricating circuit as specified above.
Multigrade oil 5W40 should ideally be used in mechanical-hydraulic control-
lers with a separate oil sump, unless the technical documentation for the
speed governor specifies otherwise. If this oil is not available when filling,
15W40 oil may be used instead in exceptional cases. In this case, it makes
no difference whether synthetic or mineral-based oils are used.
The military specification applied for these oils is NATO O-236.
Washing ability
Dispersion capability
Neutralisation capability
Evaporation tendency
Additional requirements
Doped oil quality
Cylinder lubricating oil
Oil for mechanical/hydraulic
speed governors
Specification of lubricating oil (SAE 40) for operation with MGO/MDO and biofuels
D010.000.023-07-0001
General
2017-07-13 - de
010.000.023-07
MAN Diesel & Turbo
2 (5) D010.000.023-07-0001 EN