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VARIANT 5
Task 1. Read the following text to answer these questions.

jjj)    What arrangements does the main steam system include?
kkk)    What valves are fitted on the superheated steam piping?
lll)    Where does steam go fr om the low pressure turbine?
mmm)    What systems and machinery use auxiliary steam?
nnn)    What does the term "desuperheated" mean?
ooo)    What is the gland sealing system used for?
ppp)    What are the two kinds of leakage occurring in the turbine casing?
qqq)    Where do the condensate and feed systems begin and wh ere do they end?
rrr)    What do we call water collected at the bottom of the condenser?
sss)    Why is the condenser called a heat exchanger?
ttt)    By what means are non-condensable gases removed from the condenser?
uuu)    Can you explain the meaning of the term "standby condition"?
vvv)    In what units is vacuum expressed in the text?

Steam Systems
On many ships, the Main Steam System includes only the piping, which carries superheated steam from the boilers to the propulsion turbines, the turbo-generators, and the soot blowers. On some modern ships, the main steam system is more complex because more units use superheated steam.
For ahead operation, the superheated steam passes through the main steam strainer, a stop valve, and a throttle valve before entering the high pressure turbine. From the high pressure turbine, the steam passes through a cross-over pipe to the low pressure turbine, then it exhausts to the condenser.
For astern operation, the superheated steam passes through the steam strainer and through a stop valve, then it goes to the steam chest of the astern turbine, which is located at one end of the pressure turbine.
Auxiliary Steam Systems supply saturated steam at the pressures and temperatures required for the operation of many systems and units of machinery. Air compressors, whistles and sirens, fuel oil tank heating coils, air ejectors, forced draft blowers and pumps are typical of the systems and machinery that use auxiliary steam on most steam-driven ships.
On ships having single-furnace boilers, all steam goes through the superheater and the steam, which is required for auxiliary steam systems, is then desuperheated.
The Auxiliary Exhaust System receives exhaust steam from pumps, namely feed pumps, and other auxiliaries, which do not exhaust directly to a condenser. Auxiliary exhaust steam is used in various units, deaerating feed tanks, distilling plants, and turbine gland sealing systems. The pressure in the auxiliary system is maintained at 15 psig.
Gland sealing steam is supplied to the shaft packing glands of propulsion turbines and turbogenerator turbines to seal the shaft glands against two kinds of leakage: (1) air leakage into the turbine casings, and (2) steam leakage out of the turbine casings. Pressures in the gland seal system are low, ranging from about 3/4 psig to 2 psig, depending upon the conditions of operation.

Condensate and Feed Systems
The condensate and feed systems include all the piping that carries water from the condenser to the boilers and from feed tanks to the boilers. The condensate system includes the main and auxiliary condensers, pumps and piping. The boiler feed system includes the main feed pump, and the piping required to carry water from the deaerating feed tank to the boilers. Together, the condensate and feed systems begin at the condenser and end at the economizer of the boiler.
The main condenser is a heat exchanger in which exhaust steam is condensed as it comes in contact with tubes through which cool seawater is flowing. The steam enters at the top of the condenser and the water (now called condensate) collects at the bottom of the condenser, below the tubes. The main condenser is maintained under a vacuum of approximately 27 to 29.5 inches of mercury.
The condensate pump pumps the condensate from the condenser to the deaerating feed tank. As a rule, two condensate pumps are used for each condenser; under normal conditions, one pump is in use and the other is kept in standby condition.
The function of an air ejector is to remove air and other non-condensable gases from the condenser. An air ejector is a type of jet pump, containing no moving parts. The flow through the air ejector is maintained by a jet of high velocity steam passing through a nozzle.

Task 2. Match each item in column A with appropriate item in column B.
Example: 2 - j.
A    B
94.        Steam    www)        boilers
95.        Heating    xxx)        operation
96.        Turbo    yyy)        valve
97.        Auxiliary    zzz)        generators
98.        Air    aaaa)        exchanger
99.        Superheated    bbbb)        steam system
100.        Forced    cccc)        ejectors
101.        Ahead    dddd)        leakage
102.        Saturated    eeee)        steam
103.        Throttle    ffff)        coils
104.        Single-furnace    gggg)        draft
105.        Air    hhhh)        condition
106.        Heat    iiii)        pump
107.        Stand by    jjjj)        steam
108.        Jet    kkkk)        chest

Task 3. Try to explain

    the way of the superheated steam in different operation modes;
    the function of the piping, heat exchanger, condensate pump, air ejector.

Task 4. Describe the distinctions between the superheated and saturated steam.
Task 5. What are the names of these objects?
System and machinery that use:
    auxiliary steam;
    auxiliary exhaust steam.

Task 6. Make a list of components of Condensate and Feed Systems.

Task 7. Put the statements in the correct sequence.

109.    The system the piping soot main includes only the and turbo-generators steam the blowers.
110.    For operation many of supply auxiliary and saturated systems units of steam machinery systems steam the.
111.    Pressure maintained system at the auxiliary in the 15 is psig.
112.    Includes the condensers piping the system pumps and main auxiliary condensate and.
113.    System the piping feed the includes pump and feed the boiler main.
114.    Are condenser for pumps a condensate used rule each as two.

Task 8. Complete the sentences with the correct form of the verb in the box

be    desuperheat    keep    condense    be    locate    maintain    pass

On some modern ships, the main steam system ________ more complex. From the high pressure turbine the steam ______________ through a cross-over pipe to the low pressure turbine. The astern turbine _______________ at the end of the pressure turbine. The steam ____________. Exhaust steam ______________ in a heat exchanger. The main condenser ______________ under a vacuum of approximately 27 to 29.9 inches of mercury. One pump _________ in use and the other _________ in standy condition.

Task 9. Write a brief description of Main and Auxiliary Turbines. It must consist of some paragraphs. Your description should answer these questions.

    What are they designed to?
    What do they consist of?
    What are the similarities and distinctions between the two principal types of turbines?

Task 10. Translate the extract on Procedure for Placing the Propulsion Plant in Readiness for Getting Under Way.

115.    With permission, engage the jacking gear and start jacking the main engines.
116.    Open the main injection and overload discharge valves, vent the main condenser.
117.    Start the main circulating pump.
118.    Start a main condensate pump; recirculate condensate through the air ejector condenser back to the main condenser.
119.    Cut in steam to the main turbine gland seal and start the gland exhaust fan.
120.    Cut in steam slowly to the second stage of the main air ejectors.
121.    Warm up one main feed pump.
122.    Energize and test the shaft revolution indicator and the engine order telegraph.
123.    Shift from the emergency feed pump to the main feed pump. (Secure the emergency feed pump in standby condition).
124.    Open wide the bypasses on the main steam bulkhead stop valve.
125.    Start warming up the main steam line.
126.    Open the drains from the whistle and cut in steam to the whistle slowly.
127.    When main condenser vacuum reaches 20 inches, shift the auxiliary exhaust and low pressure drains to the main condenser.
128.    Test the steering engines. Log the results of the tests in the Engineering log.
129.    Warm up and test the standby auxiliary machinery: condensate pump, main feed booster pump and main feed pump.
130.    Warm up an additional ship's service turbogenerator.
131.    When the required number of boilers are on the line, split the following system:
132.    main steam, auxiliary steam, 150 psi steam, auxiliary exhaust, high pressure drains, main condensate, makeup feed, fire main, inspection tank drains, and (if applicable) turbogenerator steam. Parallel and then split the electrical load.
133.    Request permission from the officer of the watch to test the main engines.
134.    With permission, stop and disengage the jacking gear, open wide the main steam boiler stops, and main steam bulkhead stops, open the main engine guarding valve 5 turns, and cut steam into the first stage of the main air ejectors.
135.    Test the main engines.
136.    When the main engines have been tested, report the engineering department readiness for getting under way. Open wide the main engine-guarding valve. 31 Spin the main engines every 3 to 5 minutes.
137.    Take and log the main engine "hot clearances".
138.    Get under way when ordered.
139.    Close the main turbine drains.