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Why is it undesirable to allow a turbine to expand in the art direction? ----CORRECT ANSWER---------------The expansion and contraction from large temp changes may cause severe damage to the turbine One of the two basic methods and designs that meet both the rigidity and expansion requirements of a turbine foundation is what? ----CORRECT ANSWER--------------- Flexible I beam What nozzle diaphragm can admit steam in an arc of a circle? ----CORRECT ANSWER- --------------Partial admission What nozzle diaphragm has the nozzle extending around the entire circle of the blades? ----CORRECT ANSWER---------------Full admission What device helps to prevent air from entering the turbine when pressure within the casing is below atmospheric pressure ----CORRECT ANSWER---------------Shaft packing gland In general, how many different types of shaft glands are used on naval turbines? ---- CORRECT ANSWER---------------Three Which is the following packing gland is the most widely used method of sealing a turbine shaft in naval turbines? ----CORRECT ANSWER---------------Labyrinth packing
What is gland seal used for? ----CORRECT ANSWER---------------To prevent the flow of air into a turbine What is the maximum gland seal pressure in pounds per sq inch? ----CORRECT ANSWER---------------.5 to 2 Which of the following collects and condenses the steam that leaks from the gland, thus preventing the escape and loss of steam to the atmosphere? ----CORRECT ANSWER-- -------------Gland leak off piping What fan type puts a slight vacuum on the leak off piping? ----CORRECT ANSWER------ ---------Gland seal exhauster The vacuum draws the leak off steam through a gland exhaust condenser, where the steam is condensed and returned to what system? ----CORRECT ANSWER--------------- Feed What term describes the thin metal strip covering the ends of the turbine blades? ---- CORRECT ANSWER---------------Shrouding Which of the following principal pumps is driven by aux turbines? ----CORRECT ANSWER---------------Fire pumps What component receives feed water and serves as a place for the accumulation of the saturated steam which is generated in the tubes? ----CORRECT ANSWER--------------- Steam drum
What term describes energy within steam? ----CORRECT ANSWER--------------- Enthalpy What type of energy is found in the water of an operating boiler? ----CORRECT ANSWER---------------Thermal Chemical energy is converted to thermal energy in what component? ----CORRECT ANSWER---------------The steam drum Thermal energy of steam is converted to mechanical energy in which component? ---- CORRECT ANSWER---------------The main feed booster pump How many foot pounds is one horse power converted to? ----CORRECT ANSWER------- -------- 550 What parts of a reaction turbine serve the same purpose as the nozzle of an impulse turbine? ----CORRECT ANSWER---------------Fixed blades and moving blades As the steam passes across the moving blades in a reaction turbine, what happens to the pressure and velocity? ----CORRECT ANSWER---------------They decrease What NSTM deals with propulsion and SSTG Turbines? ----CORRECT ANSWER--------- ------NSTM 231 Whats type of rotary pump is frequently used as a lubricanting pump on pumpe and other aux equipment? ----CORRECT ANSWER---------------Simple gear pimp
What is the normal length of a tapered plug? ----CORRECT ANSWER---------------3" What is installed on a non-condensing turbone to protect turbine casing from excessive pressure? ----CORRECT ANSWER---------------Combination exhaust relief valve 2-3 psi above exhaust line pressure On an SSTG, what protects turbine casing from excessive pressure? ----CORRECT ANSWER---------------Back pressure trip When starting an SSTG, what is a minimum lube oil temp? ----CORRECT ANSWER----- ----------60 degrees What are the four sections of a PQS? ----CORRECT ANSWER--------------- Fundamentals, systems, watchstations, qual card What is the number for a PMS feedback report? ----CORRECT ANSWER--------------- 4790/7B When should oil coolers be put into operation on aux machinery? ----CORRECT ANSWER---------------When temp of lube oil leaving cooler is 100 degrees DFT is designed to operate at what pressure and temp? ----CORRECT ANSWER--------- ------15 psi and 240- 25 0 degrees What is installed on a centrifugal pump to eliminate renewing of an entire propellor and pump casing due to rapid wear? ----CORRECT ANSWER---------------Wearing rings
What is QA chapter 10? ----CORRECT ANSWER---------------Quality assurance records What is QA chapter 9? ----CORRECT ANSWER---------------Audits, surveillance, evaluations and assesments What is QA chapter 3? ----CORRECT ANSWER---------------PQS and training What is QA chapter 2? ----CORRECT ANSWER---------------Quality maintenance process What is QA chapter 4? ----CORRECT ANSWER---------------Welder, brazer, and NDT qualifications What is QA chapter 5? ----CORRECT ANSWER---------------In process control When is the current ships maintenance project verified and updated? ----CORRECT ANSWER---------------Monthly PMS schedules are categorized in what manner? ----CORRECT ANSWER--------------- Cycle, quarterly, weekly Main feed pump is classified as what type of pump? ----CORRECT ANSWER--------------
- Multi stage High speed Turbine driven How long must the engine room/fire room operating log be kept for? ----CORRECT ANSWER---------------2 years
Main feed pumps are fitted with what two types of governors? ----CORRECT ANSWER- --------------Speed limiting Constant speed the number of revolutions to major speed change is entered in what column? ---- CORRECT ANSWER--------------- 3 Entries for astern pitch are preceded by what level? ----CORRECT ANSWER--------------
- B What is the max allowable super heater outlet temp during transition periods of 15mins - 1 hour on a 1200 psig D type boiler? ----CORRECT ANSWER---------------1020 degrees What is the first action taken, when you are experiencing difficulty in maintaining boiler water level on an automated ship? ----CORRECT ANSWER---------------Shift boiler feed water control to remote/manual In the engineering bell book, what does I mean? ----CORRECT ANSWER--------------- Ahead standard speed In the engineering bell book, what does III mean? ----CORRECT ANSWER--------------- Ahead flank speed In the engineering bell book, what does B 1/3 mean? ----CORRECT ANSWER------------- --Back 1/3 speed
A ruptured feed water control valve diaphragm will have what adverse effect on boiler water level? ----CORRECT ANSWER---------------Water level increase Valve will fail open Maximum steady state superheater outlet temp on a D type 1200 psig boiler? ---- CORRECT ANSWER---------------1000 degrees During loss of vacuum casualty on a main condenser, what action must be taken when vacuum decreases to 15"? ----CORRECT ANSWER---------------Main engine must be stopped and casualty procedure IAW EOCC Temporary distortion of SSTG rotor numerous start/stop episodes is known as what? ---
- CORRECT ANSWER---------------Bowed rotor Whenever a propulsion turbine casing joint is opened for any reason, a final contact check is required by taking a red and blue check of the made up joint, what is the required contact for non pumping groove joints? ----CORRECT ANSWER--------------- 75% contact over entire joint, 1/4" minimum continuous contact inside the groove and across each pressure section What is the function of staff packing on SSTG ----CORRECT ANSWER--------------- Prevent leakage of stem from ingress of air into turbines Prior to conducting thrust measurements on a main engine, turbine must be at ambient temp with throttles shit for how long? ----CORRECT ANSWER---------------24 hours Main engine turbine bearings are measured for wear at what normal interval? ---- CORRECT ANSWER---------------Annually
Lube oil cooler should be bypassed on operating aux turbine until discharge oil temp reaches what temp? ----CORRECT ANSWER---------------100 degrees IAW EOCC procedures, what three casualties require lifting of boiler safety valves? ---- CORRECT ANSWER---------------Ruptured boiler tube Low water in boiler Major uncontrolled flooding A reduction gear journal bearing shows dramatic increase in temp and then decrease to ambient temp, this is called what? ----CORRECT ANSWER---------------Wiped bearing How long is the engineering log kept for? ----CORRECT ANSWER---------------3 years, 3 120/ How long is the engineering bell book kept for? ----CORRECT ANSWER--------------- 3 years, 3120/ Engineering bell book symbol 1/3? ----CORRECT ANSWER---------------Ahead 1/ speed Engineering bell book symbol 2/3? ----CORRECT ANSWER---------------Ahead 2/ speed What type of availability is used for repairs while ship is underway? ----CORRECT ANSWER---------------Voyage repair availability What does the term locked train reduction gear refer to? ----CORRECT ANSWER-------- -------2 first reduction pinions are locked between first two reduction gears and transmit power from the turbine equally to two gears
What is the most common sealant that is used on turbine casing joints? ----CORRECT ANSWER---------------Copalite What is the most common cause of turbine blade failures? ----CORRECT ANSWER------ ---------Resonate blade vibration Steam turbine rotors and bearings are classified as what level of repairable parts? ---- CORRECT ANSWER---------------Depot level After installing new bearings on SSTG reduction gear, what is required tooth contact? -- --CORRECT ANSWER---------------90% What type of propellor cleaning uses non siliceous material? ----CORRECT ANSWER--- ------------Hone blasting SSTG gland sealing steam pressure has a range of what? ----CORRECT ANSWER------ ---------1/2-2 psi What type of turbine blowing is used for installation in circumference grooves? ---- CORRECT ANSWER---------------Tee root blowing What is the most common used propulsion turbine? ----CORRECT ANSWER--------------
- Type II A straight through What is the range of the thermometer in API gravity test? ----CORRECT ANSWER------- ---------5 to +215 degrees
What is the general allowable thrust clearance play on an aux turbine? ----CORRECT ANSWER---------------.010 -. What device is installed to stop high pressure air compressor automatically when the cooling water rises above a safe limit? ----CORRECT ANSWER---------------Auto temp shut down device When replacing a propulsion turbine journal bearing, the rotor must be lifted vertically to what max height in order to ease the removing of lower half of bearing? ----CORRECT ANSWER---------------.005" What are the five wet lay up methods? ----CORRECT ANSWER---------------Steam blanket Nitrogen Hot deaerated fill Sodium nitrate Hydrazine/morpholine What are the two dry lay up methods? ----CORRECT ANSWER---------------Heated air Desiccant When is a steam blanket lay up considered lost? ----CORRECT ANSWER--------------- Boiler steam pressure falls to atmospheric pressure and can not be re established Deaerated feed water used in hot deaerated backfill lay up shall meet what dissolved oxygen limit? ----CORRECT ANSWER---------------15ppb Who administers hydrazine/morphine lay up? ----CORRECT ANSWER--------------- Industrial activity Ships force when chelant is used
Air lock is designated to hold for what min time frame IAW PMS ----CORRECT ANSWER---------------10mins What is set point adjuster set at to maintain a normal water level on a 3 element feed water control system? ----CORRECT ANSWER---------------9 psi An example of a final control element in 3 element feed system would be what? ---- CORRECT ANSWER---------------Feed water control valve What is the desired set point on a general regulator steam pressure transmitter? ---- CORRECT ANSWER--------------- 7 psi Effective loading pressure range on a general regulator combustion control system? ---- CORRECT ANSWER--------------- 3 - 15 psi What tool is used to split boiler tubes in preparation for removal? ----CORRECT ANSWER---------------Safety ripping chisel Rotary soot blowers are tested IAW PMS to have operating pressure of what? ---- CORRECT ANSWER---------------300 +- 25 psi What at prohibits any person to discharge oil from any water borne vessel or ashore or offshore facility into/upon certain waters and established restrictions within contiguous zone ----CORRECT ANSWER---------------Federal water pollution act 1970 What are the two principal parts of an air register? ----CORRECT ANSWER--------------- Diffuser, air foils
What is the max rpm differential on two FOB operating in parallel? ----CORRECT ANSWER---------------300 rpm What is the purpose of scavenging air connection located on soot blower head? ---- CORRECT ANSWER---------------It supplies air to soot blower element to prevent the combustion gases from backing up into soot blower head or steam piping An insulating block is capable of withstanding surface temp of what? ----CORRECT ANSWER---------------1500 degrees If ignition fails to occur within two or three seconds, what action must be taken? ---- CORRECT ANSWER---------------Shot burner fuel oil manifold valve safety shit off device and investigate cause What is the purpose of the gland dealing system? ----CORRECT ANSWER---------------It prevent steam from leaking out of the main engine and from air entering How are flanges installed in a non ferrous system? ----CORRECT ANSWER--------------- Brazing How often are fuel tanks emptied to reduce heavy sludge deposits? ----CORRECT ANSWER---------------Every 12 months What lubricated corrugated ribbon packing? ----CORRECT ANSWER--------------- Graphite What must be done to lube oil coolers that are online more than 24 hours? ---- CORRECT ANSWER---------------Drain seawater side
What type of reduction gear would you expect to find in aux type shop? ----CORRECT ANSWER---------------Tandem articulated Double reduction With one or more inputs Typical end play with cold engine is what? ----CORRECT ANSWER---------------.008- .014" What type of gauge is used to measure clearance between high pressure and low pressure turbines? ----CORRECT ANSWER---------------Taper gauge Chloride is an indication of what type of contamination? ----CORRECT ANSWER--------- ------Sea water How are steel flanges installed in systems? ----CORRECT ANSWER---------------Welding What type of corrosion is caused by shore water contamination? ----CORRECT ANSWER---------------Caustic Max silica content of shore source feed water ----CORRECT ANSWER---------------. ppm What is primary source of silica contamination? ----CORRECT ANSWER--------------- Poor quality shore feed water Which dishwasher is fully automatic? ----CORRECT ANSWER---------------3 tank machine
Max moisture content of an oil sample drown from centrifugal compressor? ---- CORRECT ANSWER---------------100ppm Main condenser is what type of heat exchanger? ----CORRECT ANSWER--------------- Cross flow When stripping fuel oil tanks, system is aligned to draw off how many gallons of fuel? ---
- CORRECT ANSWER--------------- 150 - 300 gallons Time limit on sodium nitrate wet lay up? ----CORRECT ANSWER---------------No time limit What device is installed on main engine thrust bearing to indicate flow? ----CORRECT ANSWER---------------Sight flow indicator Boiler full power capacity will be affected if what percent of generating tubes are plugged? ----CORRECT ANSWER--------------->5% When warming up a propulsion turbine the turbine should be rotated with steam at which interval? ----CORRECT ANSWER--------------- 2 - 3 mins Main reduction gear dehumidifier system must be checked at what frequency for correct operation? ----CORRECT ANSWER---------------Daily All boiler tubes are identified in what manner? ----CORRECT ANSWER---------------Tube rows by lettering Individual tubes in each row by numbers
