Crankcase Ventilation System - Wartsila 31 Product Manual

Wärtsilä 31 Product Guide
7.3.4 Pre-lubricating oil pump (2P02)
The pre-lubricating oil pump is a scew or gear pump, which is to be equipped with a safety
valve.
The installation of a pre-lubricating pump is mandatory. An electrically driven main pump or
standby pump (with full pressure) may not be used instead of a dedicated pre-lubricating
pump, as the maximum permitted pressure is 200 kPa (2 bar) to avoid leakage through the
labyrinth seal in the turbocharger (not a problem when the engine is running). A two speed
electric motor for a main or standby pump is not accepted.
The piping shall be arranged so that the pre-lubricating oil pump fills the main oil pump, when
the main pump is engine driven.
The pre-lubricating pump should always be running, when the engine is stopped.
Depending on the foreseen oil temperature after a long stop, the suction ability of the pump
and the geometric suction height must be specially considered with regards to high viscosity.
With cold oil the pressure at the pump will reach the relief pressure of the safety valve.
Design data:
Capacity
Max. pressure (safety valve)
Design temperature
Viscosity for dimensioning of the electric
motor
7.3.5 Pressure control valve (2V03)
Design data:
Design pressure
Capacity
Design temperature
7.3.6 Lubricating oil pump, stand-by (2P04)
The stand-by lubricating oil pump is normally of screw type and should be provided with an
overflow valve.
Design data:
Capacity
Design pressure, max
Design temperature, max.
Lubricating oil viscosity
Viscosity for dimensioning the electric
motor
7.4

Crankcase ventilation system

The purpose of the crankcase ventilation is to evacuate gases from the crankcase in order to
keep the pressure in the crankcase within acceptable limits.
Wärtsilä 31 Product Guide - a1 - 18 October 2016
see Technical data
350 kPa (3.5 bar)
100°C
500 cSt
1.0 MPa (10 bar)
Difference between pump capacity and oil flow through engine
100 °C
see Technical data
0.8 MPa (8 bar)
100°C
SAE 40
2
500 mm /s (cSt)
7. Lubricating Oil System
7-11