Coolers Flashcards
How is a pipe cooler constructed?
Cooper tubes running horizontally through a housing while the cooling medium flows over the cooper tubes.
Draw a diagram of a pipe cooler, showing its construction?
See one note
How would you test a cooler?
Hydrostatic pressure test - 1.5 times operating pressure
What would you do if you had a leak from this cooler?
Identify which fluid is leaking and either replace a gasket or if possible replace the tube but in some cases we can plug a tube
How can you temporarily repair this cooler?
If the tube has failed then we can plug that one tube to ensure we can stay operational till it can be corrected
What are the consequences of water in the lub oil?
Oil and water becomes emulsified, this would block passageways and the viscosity would be reduced, this reducing heat transfer.
It can also reactive with the additives and form acids, accelerating corrosion and wear.
What are the consequences of fuel in the lub oil?
Dilution of the oil, reducing its viscosity.
Chemical reaction from additives in the oil.
Combustion residues creating sludge deposits, blocking pathways and reducing heat transfer
How do you test for them?
By completing lub oil analysis
How would you check the efficiency of a shell/tube cooler?
- Completing visual inspections of the heat exchanger
- Comparing the inlet and outlet temperatures to previous readings that have been taken on the log.
Sea water differential rising, what are your actions?
This implies that there is a blockage or fowling. If possible the cooler will be back flushed by reversing some valves.
If not possible then the cooler will have to be isolated, opened, cleaned and returned to service
Log all in PMS and logbook
Sea water outlet temp at cooler dropping and engine running hotter, cause / actions?
Could be fouling in the heat exchanger or fowling in the sea strainers. We would check the pressure gauges on both units and see where the fault is. The rectify accordingly.
What material are plate coolers and how do they work?
Can be either stainless steel or titanium
They work by multiple thin plates with corrugated channels stacked on each other with a gasket sealing them together. The two fluids flow through alternative channels and allow for heat transfer.
