Transcript Document

Tomislav Skračić, MA
Undergraduate English
Course for
MARINE ENGINEERS
5th Semester
Essential reading:
SPINČIĆ, A., PRITCHARD, B., An English Textbook For
Marine Engineers 2., Pomorski fakultet, Rijeka 2009.
LUZER, J., SPINČIĆ, A., Gramatička vježbenica engleskog
jezika za pomorce, Pomorski fakultet, Rijeka 2003.
Lesson 14
WATER COOLING SYSTEM – Review
verb “provide” & noun “provision”
verb “PROVIDE”
“PROVIDE” is a common verb in technical texts and materials:
 Thermostatic valves are
provided to regulate the flow of
either the fresh water or the sea
water.
 To reduce the corrosive action
and inhibit the formation of
scale deposits in the system it
is usual to provide some form
of water treatment.
 In order to compensate for air
which may become dissolved in
the water and released when
heated, an open tank is
provided at the height above
the highest point of the system.
U sustavu hlađenja su postavljeni
(ugrađeni, instalirani, nalaze se)
termostatski ventili radi
reguliranja protoka slatke ili
morske vode.
Da bi se smanjilo djelovanje
korozije i spriječilo stvaranje
kamenca u sistemu, obično
postoji (se vrši) neka vrsta
obrade vode.
Da bi se nadomjestio zrak koji
može biti otopljen u vodi i
ispušten kada se zagrije, na
visini iznad najviše točke sistema
(hlađenja) nalazi se (ugrađen je,
montiran je) otvoreni tank.
Glagol “provide” može se zamijeniti s “there is…”, “fit”, “mount”,
“build in”, “install”, “supply”, npr:
1.
2.
3.
a) There are thermostatic valves to regulate the flow of
either the sea or the fresh water.
b) Thermostatic valves are fitted (supplied, mounted,
placed, installed, built in) to regulate the flow of either
the fresh or the sea water.
a) … in the systems, there is some form of water treatment.
b) … it is usual to install (fit) some form of water treatment.
a) … and released when heated, there is an open tank at
the height above…
b) … and released when heated, an open tank is fitted
(mounted, installed, built in, placed) at the height
above...

Te zamjene (there is, fit, mount, install, build in, supply)
odgovaraju našim glagolima “nalazi(e) se”, “postoji(e)”,
“ugraditi”, “montirati”, “instalirati”, “postaviti”.

Glagol “provide” najčešće je u pasivnom obliku i označava
postojanje ili položaj nečeg. Osim toga glagol “provide” često
znači i “dati”, “pružiti”, “osigurati”, (give, offer, ensure):
e.g. Automatic sprinkler system provides the highest level of
safety on board. = Automatski sprinkler-sistem pruža (daje)
najveću sigurnost na brodu.
noun “PROVISION”
Slično je i sa imenicom “provision”:
 The provision of a
water treatment system
was urgent.
 Provision must be made
for a new water
treatment system.
(kolokacija “make
provision for”)
Bilo je hitno ugraditi
(montirati, postaviti)
sistem obrade vode.
Mora se postaviti
(osigurati) novi sistem
obrade vode.
Exercise 1 – Rearrange these sentences using the verb
“provide”. Make all necessary changes.
Example:
There are doors on the cylinder casing, through
which the water spaces may be cleaned
inspected when overhauling the
and
engine.
>>> Doors are provided on the cylinder casing,
through
which the water spaces may be
cleaned and
inspected when overhauling
the engine.
1. These manufacturers supply the piston rings which can be
run in quickly.
2. Modern medium-speed engines are turbocharged.
3. There is a control bore in the cylinder cover to enable
possible gas leakage to be detected between the two parts
Exercise 1 – Rearrange these sentences using the verb
“provide”. Make all necessary changes.
4.
5.
6.
7.
8.
The new maintenance system ensures higher reliability and
lower costs.
On most engines sea water and fresh water pumps are
fitted.
This design is termed the “coctailshaker”, the motion of the
oil offering extremely good heat transfer.
In the cylinder head there is an indicator for measuring the
cylinder pressure.
The cylinder cover-insert is fitted with the necessary bore
holes to accommodate the valves.
Exercise 2 – Translate into English using the verb
“provide”:
a) Na ulasku u cirkulacionu pumpu nalazi se filter goriva.
b) Ovaj brod pruža najbolje uvjete života posadi.
c) Na jednom kraju klackalice nalazi se vijak za podešavanje
zračnosti ventila.
d) Ugradnjom manometra pritisak se može stalno kontrolirati.
e) Većina srednjehodnih dizel motora izvedena je s direktnim
prekretanjem.
f) Na glavi cilindra montiran je i ventil uputnog zraka.
g) Da bi se ležajevi zaštitili od korozije oni imaju tanki sloj
indija ili olova.
Water cooling system – REVIEW
1. HEAT SOURCES
 Burning of fuel
 Heat developed by compression of air
 Frictional heat
2. HEAT DISTRIBUTION
 1/3 = converted into useful work (transferred into mechanical
energy / BHP).
 1/3 = lost as exhaust gases
 1/3 = lost for cooling / absorbed by metallic walls of the
combustion chamber.
3. OVERHEATING
 Breakdown of L.O. Film
 Loss in material strenght
 Excessive stresses due to unequal temperatures
 Faliure to maintain proper clearances between running parts.
4. COOLANTS
 Fresh water
 Luboil
5. COOLING WATER TEMPERATURE
5.1 The temperature should be kept as high as possible.
5.2 If too high, it will cause boiling of water and formation of
scale deposits (incrustration)
5.3 If too low, it will lead to condensation of combustion gases
on the liner surfaces.
5.3.1 Products of condensation may:
 contain acids causing corrosion
 cause so called cold sludge in the L.O. increasing
wear in all moving parts
6. COOLING WATER TREATMENT & CONSEQUENCES

If the cooling water is not properly treated, the closed
cooling systems may undergo fouling, formation of deposits
(preventing or disturbing the heat transfer). The deposit
consists of loose sludge and solid particles.

Removal: mechanically (first brushed or rinsed off with
water) or chemically.

Narrow spaces are chemically cleaned.

Limestone deposits can be cleaned with acid solution.
7. WATER COOLING SYSTEMS
 Large slow speed, two stroke engines have 2 separate
closed cooling circuits.
 A header or expansion tank allows venting of the system.
The header has connections from engine discharge & pump
suction line.
 A heater is fitted with by pass to warm the engine when
necessary.

Cylinder jacket system
Water → lower end of the jacket → cylinder cover → exhaust
valve cages → turbocharger → turbine cooling spaces → air
separator → main discharge.

The piston cooling system
Water → piston cooling tank → piston water cooler → piston
cooling connections → return by gravity to supply tank.