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Replacing boiler gauge glass,

Replacing boiler gauge glass,

watch following video

Axial damper.

The engine is equipped with an integrated axial damper. The duty of the axial
damper is the reduction of axial vibrations.
The damper consists of an upper , and a lower cylindrical part , which are both
screw fastened to the last bearing girder, and of a damping flange  which is a
part of the crankshaft. The oil quantity required for the damping is adjusted by
means of a throttling valve.

The engine is equipped with an axial damper monitoring system arranged above
the end casing at the free end. 
The oil pressure in the aft side and fore side chamber
of the axial damper is monitored, and in case of oil pressure drop an alarm is
triggered (setting values see Alarms and Safeguards .

The reason for this alarm must be investigated and remedied:
 

Orifices in the pressure gauge pipes clogged
 
Shut-off valves closed in the pressure gauge pipes

 Low oil pressure and / or high oil temperature in the bearing oil system
 
Throttle valve mal-adjusted
 
Excessive wear of the sealing rings, e.g. caused by dirt particles (clearance
too big).

Thrust Pads in RT flex

In fixed pitch propeller plants the respective execution for right hand or left hand
rotating engines has seven thrust pads on either side of the thrust bearing flange,
each adapted to the respective sense of rotation.

In controllable pitch propeller plants the thrust bearing is equipped on either
side with two thrust pads each for left hand and right hand rotation respectively

The thrust pads are lubricated with bearing oil which is led by lubricating oil pipe
to spray nozzles . The nozzles are dimensioned in such a way that in operation
an oil film forms between thrust bearing flange  and thrust pads (hydraulic

wedge)

Hot Lay-up

In this lay-up condition, the machinery is kept
in operation for the sake of fast recommissioning,
but measures may be taken to
reduce various operational costs

Hot lay-up for up to one month

This lay-up condition is suitable for 24 hours
re-commissioning time. During this period, the
vessel complies with classification and flag
state requirements. The crew may be reduced
to the level as required by safe manning
certificate. Machinery will be kept running
with consideration to minimum consumption.
Normally no return on insurance fee applies

during the first 30 days idle.

Hot lay-up for up to three months

Insurance lay-up returns may be granted for
idle periods exceeding 30 days. If manning
reductions below safe manning certificate
limits are considered

Hot lay-up for up to twelve months

This condition is suitable for 1 week recommissioning
time. When the vessel is laid
up or otherwise taken out of service for a
period of more than 3 months, notifications on
lay-up should be issued to the classification
society and flag state. Manning may then be
reduced below the safe manning certificate
limit in agreement with the flag state, the
classification society, other local authorities
and insurance companies. Most port authorities
will have local requirements on laid-up
vessels, such as oil pollution coverage, wreck
removal or minimum manning.
ISM and ISPS certificates are still valid but
additional verification shall be performed to reinstate
both certificates upon recommissioning.
See Section 5 for details on

ISM and ISPS.

Single Phase Induction Motor, How it works ?

Replacing A Gauge Glass (+playlist)

Spectroscopy,metals analysis

Spectroscopy

Spectrographic metals analysis is usually the 'heart' of most oil analysis programs.  Using either a Rotrode Emission Spectrometer or an Inductively Coupled Plasma Spectrometer (ICP), 20 or more metals can be simultaneously determined.  The metals analyzed for include wear, additive, and contaminant metals and are reported in parts per million (ppm). 

Laboratories uses a Rotating Disk Emission Spectrometer. The instrument is quick and easy to operate and is accurate within acceptable limits.

The Rotrode Spectrometer has a particle size detection limitation of between 3µ and 10µ (depending on the particular metal in question and the amount of surface oxidation on the particle surface) compared to the .5µ - 2µ limitation of the ICP.  Results of the Rotrode Spectrometer are accurate to about 1 or 2 ppm. 
 Results of the ICP are accurate to .1 ppm.  The advantage of the Rotrode Spectrometer is that no dilution of the sample is required, while the advantage of the ICP is its accuracy.  With proper sample preparation, an ICP can measure in the 10's of parts per billion (ppb).  

Particle size limitations of an ICP are even more sever than a Rotrode Spectrometer because the sample and particles have to be nebulized.  If measuring very low concentrations, the diluent (usually diesel fuel) has to be at least as clean. 

Corrosion Microcell

EOOW MCA ORAL EXAM DEMO

Wärtsilä Low-Speed Dual-Fuel Engines (+playlist)

Hot lay-up, Cold lay-up

Hot lay-up
Hot lay-up condition, the machinery is kept in operation for the sake of fast re-commissioning, but measures
may be taken to reduce various operational costs.

Cold lay-up
In cold lay-up condition the machinery is taken out of service and the vessel is kept “electrically dead” with the
exception of emergency power.

Single Phasing of a Motor?

Single Phasing of a Motor?

Single Phasing is where one of the 3-phase's supplying the Motor becomes disconnected.  The Motor will continue to run if this happens and can result in Motor Burnout.  The effect of Single Phasing is to increase the Current in the two remaining Lines and cause the Motor to become very noisy due to uneven Torque produced

How is 15ppm reached in an Oily Water Separator?

How is 15ppm reached in an Oily Water Separator?

15ppm is achieved in an Oily Water Separator by normally passing through a Two Stage Separator where in the first stage Oil/Water is passed into the coarse separating compartment. Here some oil will rise to the top of the Compartment due to its lower density, Heating Coils may aid this. 

  The remaining Oil/Water will flow down into the Fine separating Compartment and moves slowly between Catch Plates.  More Oil will separate out onto the underside of these Plates and travel outwards until free to rise to the oil collecting space. 

  The almost Oil Free Water (usually being at 100ppm at this stage) will then pass to the second stage of the separator, which is a Filter Unit comprising of two Filter Units.  

The first Filter Stage removes Physical Impurities present and promotes some Fine Separation. 

  The second Stage Filter uses Coalescer Inserts to achieve the fina, Oil/Water Mixture leaving this Stage at less than 15ppm.

Why is Simultaneous Injection of Fuel Oil and Starting Air into a Main Engine Cylinder Undesirable and How is it Prevented?

Why is Simultaneous Injection of Fuel Oil and Starting Air into a Main Engine Cylinder Undesirable and How is it Prevented?

Simultaneous Injection of Fuel and Starting Air into a Cylinder is Undesirable as it could lead to an Explosion in the Start Air System. 

It is prevented by means of Interlock, which prevents Fuel being Injected when the Air Start Auto Valve is Open. 

The Interlock Operates a Stop Solenoid, which keeps the Fuel Rack at Zero Position. 

What are the Safety Devices fitted to an Air Compressor?

What are the Safety Devices fitted to an Air Compressor?

Low Lub Oil Pressure Shut Down

High Air Temperature Shut Down

1st Stage Relief Valve

2nd Stage Relief Valve

A Fusible Plug is fitted after the 2nd Stage Cooler, Set at 120°C

If Water Cooled, a Jacket Water Safety Valve is fitted.

What is the Primary Function of the Expansion Valve in a Refrigeration System?

What is the Primary Function of the Expansion Valve in a Refrigeration System?

The Primary Function of an Expansion Valve in a Refrigeration System is to regulate the Flow of Refrigerant from the H P side to the L P side of the System. 

The pressure drop causes the Saturation Temperature to drop, enabling it to boil off at the Low Temperature of the Evaporator.

Cloverleafing-

Cloverleafing-
When the cyl l.o. has inadequate acid neutralising properties for the fuel being burnt or if there is insufficient quantity of oil injected then cloveleafing can occur
This is basically regions of corrosive wear midway between the quills and upwards towards the top of the liner. These areas may be visible due to the corrosive effect and they are cloverleaf shaped.
 Eventually the rings become unsupported in these areas, gas builds up on the front face and the ring is subject to collapse.

Emma Mersk

Improved High Lift safety valve material

Materials for all parts must be non corrodible. Common materials are Bronze, Stainless steel or Monel metal, depending on the conditions of service. The valve chest is normally made of cast steel.