Man B&W L35MC6-TII, Руководство по проекту

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MAN B&W 9.01
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MAN Diesel
198 74 75-3 .1 MAN B&W L35MC
Cylinder Lubricating Oil System
The cost of the cylinder lubricating oil is one of the
largest contributions to total operating costs, next
to the fuel oil cost. Another aspect is that the lu-
brication rate has a great influence on the cylinder
condition, and thus on the overhauling schedules
and maintenance costs.
It is therefore of the utmost importance that the
cylinder lubricating oil system as well as its opera-
tion is optimised.
Cylinder lubricators and service tank
The cylinder lubricators can be either the electronic
MAN B&W Alpha Cylinder Lubricators or a me-
chanical type driven by the engine. Basic design is
MAN B&W Alpha Cylinder Lubricators, EoD: 4 42
104. The options are listed in the Extent of Delivery.
The cylinder lube oil is supplied from a gravity-
feed cylinder oil service tank to where it is being
pumped from the cylinder oil storage tank. The
size of the cylinder oil service tank depends on
the owner’s and yard’s requirements, and it is
normally dimensioned for minimum two days’
consumption.
The cylinder lubricating oil consumption could be
monitored by installing a flow meter on the pres-
sure side of the pump in the supply line to the
service tank, if required by the shipowner. Pro-
vided the oil level in the service tank is kept the
same every time the flow meter is being read, the
accuracy is satisfactory.
A cylinder lubricating oil supply system for engine
plants with MAN B&W Alpha Cylinder Lubricators
is shown in Fig. 9.02.02 and for plants with me-
chanical cylinder lubricators in Fig. 9.03.03. In both
cases a dual system for supply of two different BN
cylinder oils is shown.
Cylinder oils
Cylinder oils should, preferably, be of the SAE 50
viscosity grade.
Modern highrated twostroke engines have a
relatively great demand for detergency in the cyl-
inder oil. Therefore cylinder oils should be chosen
according to the below list.
A BN 70 cylinder oil is to be used as the default
choice of oil and it may be used on all fuel types.
However, in case of the engine running on fuel
with sulphur content lower than 1.5 % for more
than 1 to 2 weeks, we recommend to change to a
lower BN cylinder oil such as BN 40-50.
The cylinder oils listed below have all given long-
term satisfactory service during heavy fuel opera-
tion in MAN B&W engine installations:
Also other brands have been used with satisfac-
tory results.
Cylinder oil feed rate (dosage)
The recommendations are valid for all plants,
whether controllable pitch or fixed pitch propellers
are used.
In case of average sulphur content, the average
cylinder oil feed rate at all loads for MAN B&W Al-
pha Cylinder Lubricator is 0.7 g/kWh. Adjustment
of the cylinder oil dosage of the MAN B&W Alpha
Cylinder Lubricator to the sulphur content in the
fuel being burnt is further explained in Section 9.02.
The nominal cylinder oil feed rate at nominal MCR
for a mechanical cylinder lubricator is typically
0.8 - 1.2 g/kWh.
Company Cylinder oil
SAE 50, BN 60-80 Cylinder oil
SAE 50, BN 40-50
BP Energol CLO 50 M
Energol CL 605 Energol CL 505
Energol CL-DX 405
Castrol Cyltech 70 / 80AW Cyltech 40 SX / 50 S
Chevron *) Taro Special HT 70 Taro Special HT LS 40
ExxonMobil Mobilgard 570 Mobilgard L540
Shell Alexia 50 Alexia LS
Total Talusia Universal
Talusia HR 70 Talusia LS 40
*) Includes Caltex, Chevron and Texaco