MAN B&W ME ENGINE

MAN B&W Overhaul video introduction Exhaust Valve and Fuel Pump

Variable Turbine Area VTA (+playlist)

lifting appliances

Why are lifting appliances ‘thoroughly examined’

A lifting appliance generally has no ‘redundancy’– so a single failure is enough to cause a major accident.
Various national regulatory schemes require that lifting appliances

 should be thoroughly examined by a ‘competent person’ at least once every 12 months. Some legal frameworks may require more frequent examinations, depending on the national authority, the competent person, and whether the equipment is used for lifting personnel.
Lifting appliances are examined in accordance with
two main legal frameworks, depending on the type of equipment and its purpose.
•
Ships’ deck cranes, engine room cranes, and lifting equipment are examined in accordance with:
- the Merchant Shipping Regulations
- flag state requirements
- International Labour Organization (ILO) Convention 152, where it applies.
Ship-mounted life saving appliances are examined in accordance with:
- Safety Of Life At Sea (SOLAS) 1974
- International Maritime Organization (IMO) LSA Code
- the IMO Maritime Safety Committee (MSC) circulars
- individual flag state requirements.
Classification societies such as Lloyd’s Register offer two survey and examination services
for lifting appliances (excluding LSA davits):
• certification
• classification
Classification is used in two situations:
• Mandatory – where the lifting appliance is the essential feature of a classed
ship. This applies for example to a heavy lift crane on a heavy lift barge, or lifting
arrangements for diving operations on diving support ships.
• Optional – when the owner requests classification, even though the lifting appliance

may not be an essential feature of a classed ship.

Engine - MAN - ME & MC Series - Fundamentals

Marine Surveyor conduct a Ship Stern Tube Inspection www.maritimeconsult...

Engine Structure Rt flex 50

Engine Structure Rt flex 50

Wärtsilä RT-fl ex50 engines have a wellproven
type of structure, with a ‘gondola’-type
bedplate surmounted by very rigid, A-shaped
double-walled columns and cylinder block,
all secured by pre-tensioned vertical tie rods.
The whole structure is very sturdy with low
stresses and high stiffness. Both bedplate and
columns are welded fabrications which are
also designed for minimum machining.
A high structural rigidity is of major
importance for the today’s two-stroke engine’s
long stroke. Accordingly the design is based on
extensive stress and deformation calculations
carried out by using a full three-dimensional
fi nite-element computer model for different
column designs to verify the optimum frame
confi guration.
The double-walled column has thick guide
rails for greater rigidity under crosshead shoe
forces. The RT-fl ex supply unit is carried on
supports on one side of the column and the
scavenge air receiver on the other side of the
cylinder jacket. Access to the piston underside
is normally from the supply unit side, but
is also possible from the receiver side of the
engine, to allow for maintenance of the piston
rod gland and also for inspecting piston rings.
The cylinder jacket is a single-piece castiron
cylinder block with a high rigidity. The
cylinder liners are seated in the cylinder block,
and are sufficiently robust to carry the cylinder
covers without requiring a support ring. A light
sleeve is applied to upper part of each liner to
form a water jacket.
The tilting-pad thrust bearing is integrated
in the bedplate. Owing to the use of gear
wheels for the supply unit drive, the thrust
bearing can be very short and very stiff, and
can be carried in a closed, rigid housing.