(1) 3. Stern tube sealing systems (service)

                                                          

This test contains questions about subjects you should (or could) know about servicing stern tube sealing systems.  Issues included are related to the technical side, different types of sealing systems as well the actual service work.

In total the test contains 60 questions for which you will get 30 minutes to complete it.

Note: once the test has been started you have the mentioned time to answer all questions, there is no way to stop and re-start the test.

 

General service knowledge

What is the function of a sealing system?

  • To prevent a fluid from going out a section
  • To prevent a fluid from going in a section
  • It works both ways

What is the correct way to replace sealing rings?

  • Replace the sealing ring(s) by means of bonding
  • Replace the sealing ring(s) by means of overhaul
(click on the answer(s) which are correct)

For replacing the sealing ring(s) by bonding you need to remove the propeller?

  • Yes, removal of the propeller is necessary.

What temperature setting do you need on the heater box for normal seal replacement on a lip-type sealing system?

  • 60°C
  • 90°C
  • 120°C

What is the minimum "bonding" time by replacing a sealing ring by means of bonding?

  • 30 min.
  • 45 min.
  • 60 min.

Shipyard dry-dock stuff

Before and after a service job you need to take the wear down readings.

With taking the wear down reading you can monitor the wear  

On a service job on an aft stern tube sealing system

you will start the job with 

Match the correct products:

  • Sealing ring
    Two component glue
  • O-cord
    Super glue
  • Gasket
    Loctite 5922

After a vessel is docked, oil is dripping from the rope guard.

  • AFT monitoring is still active
  • FWD monitoring is still active
What could be the reason?

If vessel is in drydock the AFT monitoring starts leaking, what could be the reason,

  • The rope guard is still in place
  • Valves of the AFT monitoring system are still open
  • Scaffolding is not placed correct
  • IWS plug is still installed

Put the steps of a bonding job in correct order:

  • Step 1
    check OC / drawings / spares / jig
  • Step 2
    clean al spares and bonding tools
  • Step 3
    prepare the correct glue
  • Step 4
    put the sealing ring on the shaft and secure it
  • Step 5
    apply heat
  • Step 6
    take the sealing ring out the jig and sand down the bonded surface
  • Step 7
    install the spring

General facts (1)

  • After service is provided on a FWD sealing system, only radial alignment is necessary

General facts (2)

  • After a service job on an AFT sealing system is provided, you need to check the axial alignment

General facts (3)

  • After a service job an an AFT sealing system is finished, you need to take the wear down

General facts (4)

  • Before you start a job on an AFT sealing system service, you need to take the wear down

General facts (5)

  • Below 8ºC, you need to have external heating and a tent to carry out a bonding job on a FWD sealing system

Is it wise to install a cast iron liner on the AFT sealing system:

  • Yes
  • No

Shipyard workshop stuff

Is it possible to machine a ceramic liner:

  • No
  • Yes

In a new Prime spacer ring, the necessary oil holes are already pre-drilled:

  • yes
  • no

STATEMENT: for all different seal types, the machining dimensions for the liners are identical:

  • yes
  • no

Is it possible to machine a cast iron liner:

  • Yes
  • No

What is the most common name of the "cut" on de picture below:

  • Dovetail
  • Goosetail
  • Svalehale

Lip-type sealing system

Mark the position of the standby sealing ring in de picture below (1):

Drag and drop the names of all mentioned parts to the correct position (1):

  • Cover ring
  • Support ring AFT
  • Intermediate ring
  • Intermediate ring 3S
  • AFT flange
  • Spacer ring
  • AFT liner
  • FWD flange
  • Support ring FWD
  • Cover ring, non-split
  • Clamp ring
  • FWD liner

Mark the position of sealing ring #3 in the picture below:

Mark the correct position of the size of the sealing system:

System facts FWD lip-type sealing systems (1):

  • A cast iron seal box can only be used for a FWD seal system.

System facts FWD lip-type sealing systems (2):

  • A FWD liner can be executed with a ceramic coating

System facts FWD lip-type sealing systems (3):

  • All FWD sealing systems are equipped with 2 sealing rings

System facts FWD lip-type sealing systems (4):

  • Every FWD sealing system is equipped with a circulator

Drag and drop the names of all mentioned parts to the correct position (2):

  • o-cord
  • seal size
  • seal #3
  • wear down gauge
  • seal #1
  • seal #3s
  • seal #2

Mark the position of the standby sealing ring in de picture below (2):

Drag and drop the names of all mentioned parts to the correct position (2):

  • #3
  • #3R
  • #2
  • #1

Mark the position of the intermediate ring:

Is it possible to have a 1 pipe monitoring system:

  • yes
  • no

EVA / EVK sealing system

Drag and drop the names of all mentioned parts to the correct position:

  • spare seal
  • shaft earting assembly
  • mating ring
  • inflatable seal
  • seal ring

What is the correct bonding temperature for an EVK sealing ring:

  • 90ºC
  • 130ºC
  • 150ºC

What is the minimum bonding time in case you use a heater gun for bonding an EVK sealing ring:

  • 45min
  • 60min
  • 90min

What is the maximum pressure for an inflatable seal on an EVK sealing system:

  • 3 bar
  • 6 bar
  • 9 bar

System facts about an EVA sealing system (1):

  • The water which is supplied to sealing ring #2 is salt water
  • Chamber between sealing rings #2 and #3 is atmospheric

System facts about an EVA sealing system (2):

  • An EVA aft sealing system is a combination of a face-type seal and a lip-type seal
  • Sealing ring #3 is fixed to the liner

System facts about EVA sealing system (3):

  • An EVA sealing system is a pollution free sealing system
  • The lip of the EVA sealing ring is pointing towards the aft

Mark the position were the sealing ring seals:

EVK sealing systems are the only sealing systems that use an inflatable seal:

  • yes
  • no

Issues regarding servicing an EVK sealing system (1):

  • It is required to paint a part of the shaft
  • AEGIR can supply the special paint

Issues regarding servicing an EVK sealing system (2):

  • An earthing device is not necessary in case you paint the shaft
  • The minimum curing time of the "Eagle paint" is 12hr

Issues regarding servicing an EVK sealing system (3):

  • The shaft needs to be painted to prevent it for pitting
  • Pitting can appear if the painted surface is damaged

Manebar sealing system

If the Manebar system is equipped with an inflatable sealing ring (1):

  • Servicing is possible afloat
  • Regularly the inflatable sealing ring is positioned in the AFT seal box

If the Manebar system is equipped with an inflatable sealing ring (2):

  • The shaft can still rotate when the inflatable sealing ring is inflated
  • The inflatable sealing ring is always pressuarised by the air supply of the vessel

Match the names of all mentioned parts to the correct position (1):

  • Body
    1
  • Shroud ring
    2
  • Face
    3
  • Seat
    4

Match the names of all mentioned parts to the correct position (2):

  • 1
    Body
  • 2
    Clamp ring
  • 3
    Face
  • 4
    Seat
  • 5
    Cooling chamber

A Manebar sealing system can be used in combination with?

  • Conventional oil lubricated bearings
  • Conventional sea water flushed bearing system
  • Closed fresh water system
  • Grease lubricated bearings
(click on the answer(s) which are correct)

Mark the correct position of the shroud ring:

Mark the correct position of the setting tool:

At the spare parts delivery of a split-type Manebar sealing system a sealing strip is included:

  • This sealing strip has always the correct length
  • The engineer has to cut it to the correct length

Coastguard sealing system

Drag and drop the names of all mentioned parts to the correct position:

  • bellows
  • seat
  • housing
  • cover
  • sealing ring
  • liner
  • wear down plug
  • face
  • carrier
  • main clamps

System facts about a Coastguard sealing system (1):

  • A Coastguard sealing system is a radial sealing system
  • A Coastguard sealing system is a axial sealing system

System facts about a Coastguard sealing system (2):

  • The liner of a Coastguard sealing system cannot be machined
  • A Coastguard sealing system is a so called "high pressure oil system"

Mark the position of the sealing strip:

Mark the position of the drain tank: