Mass Steam Fireman & Engineer Questions

Front 1

Most of these flashcards were from questions at Massengineers.com I answered the questions as best could.

Back 1

Good luck with your studies!

Front 2

Who is your district state inspector?

http://www.mass.gov/eopss/docs/dps/engineering/inf-eng/eng-district-map-jul16

Back 2

This is not a test question, but you need to know who the inspectors are in the district where you live and work. The inspector where you work will probably give you the oral exam.

Front 3

Time is the currency of your life, be careful not to waste it.

My two cents worth of frank honesty.

Back 3

Buy a chess clock and monitor the time you goof off compared with study and work. There's usually plenty of time to study in most boiler houses. Don't waste it! Companies will value you far more for your knowledge, than how good of a "worker" you are. Passing the exam is simply a basic requirement. You need to know your boiler house and plant too. Also, some boiler houses are unprofessional and look like "Sanford and Son". Set aside at least one hour a day for cleaning, and one hour for study. It might mean looking at floor drain blueprints, or an electrical diagram, etc.. Every place has the mechanic, electrician, fireman, etc. who is the weak-link. Be the person who solves problems that others cannot. Try the chess clock, it will keep you on track.

Front 4

What is required to sit for a 3rd engineer license?

Back 4

Must be Citizen or filed declaration to be one. Must furnish evidence of Training and experience. Must have been Employed as a Steam Engineer, Fireman, Auxiliary operator, Control Room Operator, Engineer’s Assistant, Watertender, for no less than 1 ½ Years. Held and used a First Class Fireman’s License, Equivalent Merchant Marine License, or License from another State for no Less than 1 Year.

Front 5

What can you do with this license?

(Chapter 146 section 49 paragraph 1)

Back 5

A 3rd Engineer license would allow me to be in charge of high a high pressure boiler or boilers connected to a common header up to 150 horsepower in the aggregate when burning solid fuel, or 500 horsepower when burning liquid or gaseous fuel, electric, nuclear, or any other source of heat. It would allow me to be in charge of engines or turbines up to 50 horsepower each. It would allow me to operate a 2nd class plant under the engineer in charge.

Front 6

Department of Public Safety Expectations of

Engineer In Charge

Use memory cue below

IV COMPLAINTS

Back 6

Instructions written to operators, Visits every day, Certified people perform repairs and are documented, Operation and Maintenance of boiler equipment, Posting of licenses and inspections, operators Licensed properly, Notify DPS within 24 hours of Accident/death, hospitalization, damage over $10,000, Inspection of all equipment, Notify Department of Public Safety within 7 days of accepting or leaving a position, operators Trained to use equipment, Sign Engineer’s Record Book daily and make sure all state log books are signed.

Front 7

What will you find on the boiler shell stamp?

SHIMMNYS

Back 7

S S power boiler stamp

H Heating surface

I Inspectors stamp number

M Manufacturer

M MAWP

N National Board

Y Year built

S Serial number

Front 8

How many BTU's in a boiler horsepower? Define boiler horsepower?

Back 8

33,475 Btu in one boiler horsepower bhp. 34.5 x 970.3=33,475.35

One boiler horsepower is the evaporation of 34.5lbs of water at 212°F to 34.5lbs of steam at 212°F. (note output is 80% of input so 41,840x.8=33,472)

Front 9

Btu in a horsepower hour

Back 9

2,545

Front 10

Btu in a Kilowatt hour, kWh

Back 10

3,413

Front 11

Combustibles in fuel oil

Back 11

Carbon, Hydrogen, Sulfur

Front 12

Furnace heat release

Back 12

Amount of heat in Btu per cubic foot of furnace volume per hour

Front 13

FHR for refractory walls

Back 13

35,000Btu/hour/ cu ft

Front 14

FHR for waterwalls

Back 14

100,000Btu/hour/cu ft

Front 15

Define pH

Back 15

Logarithm of reciprocal of hydrogen ions in concentration

Front 16

Difference of pH of 10 and 11

Back 16

A pH of 11 is ten times more alkaline than a pH of 10

Front 17

Why test chloride in boilers

Back 17

To determine blowdown, salt concentration cannot be above 23%,

Front 18

Which takes the most excess air, coal or oil, why

Back 18

Coal, because oil mixes with air better

Front 19

When are 2 stop valves needed

Back 19

A boiler connected to a header in battery with other boilers has a manhole

Front 20

How many Btu in a boiler horsepower? Provide calculation to prove your answer?

Back 20

33,475.4Btu, 34.5lbs of water evaporated from and at 212°F to steam requires 970.3Btu/lb, thus 970.3 x 34.5 = 33,475.4 Btu

Front 21

How do you find boiler horsepower?

Back 21

Calculate the heating surface and estimate the pounds of steam per hour and divide by34.5 which is the steam in one hp at atmospheric pressure. 8lbs per sq ft for fire tube boiler, 10lbs per sq ft for water tube boiler, 16lbs per square foot for water walls. Thus a fire tube boiler with 2000 sq ft of heating surface would be 2,000x8=16,000lbs per hour, 16,000/34.5=464hp

Front 22

How does DPS determine boiler horsepower? 4 methods.

Back 22

By the manufacturer’s stamp, by steam output divided by 34.5, by Btu per hour input divided by 41,840, by Btu per hour output divided by 33,475. On older solid fuel boilers hp can also be calculated by the grate heating surface times 3 for when safety valves are set over 25psi, or times 1.5 for safety valves set to 25psi or less.

Front 23

What is suspension, fuel bed, and over-fire burning in a furnace?

Back 23

Suspension typically refers to fluidization of solid fuel such as pulverized coal and sometimes sawdust, both of which are blown into the boiler. Hot air is introduced at multiple points under the combustion zone creating air currents that burn the fuel aloft before it can drop to the grate.

Suspension may refer to fuel oil which is atomized, or gas which is a vapor depending upon the context in which it is used.

Fuel Bed refers to the burning of solid fuels on a surface such as coal, trash, or biomass. It could be a simple grate on a hand-fired boiler, and would also include stoker-fired and traveling grate boilers.

Over-Fire Air is a method of introducing tertiary air to the combustion process. Tertiary meaning “third”, thus tertiary air is after primary and secondary air. Over-fire air is added above the top row of burners. It’s used to reduce NOx, to completely burn CO, and to aid in burning difficult solid fuels, particularly trash and biomass.

Front 24

What are thrust bearings for

Back 24

Thrust Bearings absorb end thrust and maintain axial clearance. There are two main types, Kingsbury/ Tilting Pad, and Tapered Land. They both maintain axial clearance with a thin film of lube oil between the two sides of the bearing and the thrust collar on the turbine shaft.

Front 25

Name 2 types of thrust bearings

Back 25

Kingsbury (also called Tilting Pad), and Tapered Land

Front 26

The centrifugal force created in the blades is absorbed by which bearing?

Back 26

Journal/Radial Bearings

Front 27

Name two ways to control thrust in a steam turbine

Back 27

Double Flow Casings, Opposed Flow Casings, Balance (dummy) Piston

Front 28

Describe a volute

Back 28

It is the casing of a centrifugal pump with a special shape that converts the velocity of water from the impeller to pressure. It has no guides or vanes, inlet pipe connects at the center and directs water into the “eye” of the impeller,discharge connects at the side.

Front 29

What is the function of a check valve on the discharge of a centrifugal pump?

Back 29

It prevents the pressure of the boiler from back-flowing when the pump shuts off. Onsystems with positive pressure head it can prevent the pump from spinning backwards if the pump is off.

Foot Valve –On the suction side of a pump, Itprevents the pump from losing its prime on pumps with negative suction head. (the question might have been worded incorrectly)

Front 30

What is a surface condenser, and why do you have an injector placed on it.

Back 30

A Surface Condenser is a shell and tube type heat exchanger that receives steam from the discharge of the low pressure turbine in a power plant. It cools steam into condensate and creates vacuum which increases turbine efficiency.

Injectors are used to spray steam into the surface condenser at start up so the steam can displace air, be condensed, and create vacuum.

Front 31

Surface Condenser maintenance issues

Back 31

Plugged tubes and dirty tubes, Scale build-up in tubes, Bad air ejectors, Leaky tubes from thermal expansion and contraction, Vibration damage to tubes, air leaks, Corrosion

Front 32

Howto determine fuel oil heater leak

Back 32

Condensate from the heater will have oil, boiler flame may have sparklers

Front 33

Where should fuel oil heater condensate go

Back 33

Should go down the drain to prevent possible boiler contamination if leaking

Front 34

What determines the boiling point temperature of water

Back 34

Pressure, higher pressure =higher temp, vacuum= lower temp

Front 35

Relative weight of mercury 34’ high, compared to water 34’ high

Back 35

1 ft H2O=.433psi 34x.433=14.72psi

1” mercury=.491psi 34x12= 408”, 408x.491=200.33psi (200.33/14.72=13.61)

(column of mercury is 13.61 times heavier)

Front 36

Explain metal stress

YouTube search

Real Engineering Material Properties 101

https://www.youtube.com/watch?v=BHZALtqAjeM&index=31&t=63s&list=PLX9Vxlnu3x7VfZL0SS76MzbIw5SFgjCVL

Back 36

Stress is the internal resistance metal offers to being deformed by external force. There are three types of stress, Tensile, Compressive, and Sheer. Tensile stress is force acting to pull to metal apart. Sheer stress is the strain riveted plates put on the rivets. Compressive stress is when metal is compressed as in rolling boiler tubes. Elastic Deformation is when tensile stress causes a stretching of the metal, yet the metal returns to its original shape once the force is removed. Plastic Deformation is when metal is stretched beyond its Yield Point and cannot return to its original shape once the force is removed, a bag in a boiler would be an example of this. Ultimate Strain is when force stretches metal to a point where its resistance to deformation decreases, which quickly leads to fracture. High carbon alloys are stiff and have greater resistance to deformation, but they fracture more suddenly than more ductile metals.

Front 37

What is the Factor of Safety

Back 37

It is the comparison of the tensile stress and actual working stress of steel. (actual definition) Factor of Safety, FoS, also called the safety factor, SF, is how much stronger something is constructed than the loads it is rated for. In boilers the FoS is the difference between the rated MAWP and the actual bursting pressure. Thus a boiler rated at 100psi MAWP with a factor of safety of 5 would be capable of sustaining at least 500psi before bursting. On older boilers the bursting pressure is generally 4 times MAWP. The standard for new construction is at least 5 times MAWP, though they are actually constructed to resist 7 times MAWP.

Front 38

What are condenser tubes made of

Back 38

Fresh Water-Admiralty Metal (a type of brass)

Salt Water- Aluminum-Copper Alloys, Stainless Steel, titanium

Front 39

Reduce these improper fractions to mixed numbers 3/2, 103/4, 46/3

Back 39

1½, 25 ¾, 15 1/3

Front 40

How do you know if an injector is working properly and water is going to boiler

Back 40

By the singing sound it makes or by placing a hand on it and noting that no water comes out the overflow.

Front 41

Gauge reads 150psi, what is the absolute pressure

Back 41

150+14.696=164.696,or 164.7F

Front 42

Two ways the heating value of fuel is determined

Back 42

Proximate Analysis and Ultimate Analysis

Front 43

Cause of severe pressure drop in #6 fuel line

Back 43

Empty fuel tank, Bad volume chamber (hot fuel flashing to vapor at pump), clogged strainer, oil too cold, wax buildup, bad heater, ruptured piping, bad pump

Front 44

Why do we treat boiler water in detail!

Back 44

To limit or prevent Sludge, Scale, Corrosion, and Carry Over. Proper water treatment reduces maintenance costs and extends the life of the boiler and related equipment. Softeners remove Calcium and Magnesium, Demineralizers also remove Silica. DAs heat water to remove oxygen and non-condensable gases. Sulfite or Hydrazine is added to remove residual oxygen. Sodium Hydroxide is used to elevate pH. Phosphates or Polymers are used to condition sludge. Amines are added to protect condensate lines from corrosion. Conductivity or Chlorides are tested to determine blowdown.

Front 45

What is phosphate used for in a boiler? How does pH affect phosphate?

Back 45

Phosphate is used as a sludge conditioner. It binds with calcium and magnesium molecules and makes soft sludge that sinks to the bottom of the boiler where it can be blown down. This deters scale formation on the boiler. Higher pH levels are better at keeping sludge from adhering to boiler tubes.

Front 46

What is pitting

Back 46

The formation of small divots in the surface of boiler metal, it is generally caused by low pH or Oxygen, but can be caused by excessive heat.

Front 47

Name 3 conditions that could cause low water in a boiler.

Back 47

Feed pump tripped/not working-broken shaft coupling

DA tank low level/pump cavitation

Restriction in feed piping, clogged strainer, stuck check valve

Level Sensing Devices not working

Excessive steam demand causing boiler to flash steam beyond feed water capacity

Ruptured piping or Massive tube leak (should be obvious)

Front 48

What are the safety devices on a boiler

Back 48

Safety Valves, Low Water Cut out, Alternative Low Water Cut Out, Flame Failure Eye, Air Proving Switch, High Oil Temperature cut out, Burner Controls for Air Purge, Fusible Plugs, Non-Return Valve, Check Valve on Feed line

Front 49

Is there a difference between relief and safety valves? Explain?

YouTube search

Engineering Mania 2 Safety valves

https://www.youtube.com/watch?v=0aYzgj_AXxc

Back 49

Yes, a SV is for boiling liquids and pressurized gas. It must open with a pop and close fully. It can only close when a pre determined amount of pressure, Blowback, has been reached.

A Relief Valve is for liquids that do not expand into vapors at operating pressures. It opens and closes gradually depending upon the pressure of the liquid.

Front 50

Name the two types of safety valves.

Back 50

Huddling Chamber and Nozzle Reaction

Front 51

What is the law regarding safety valves

Back 51

Every boiler must have at least one, boilers over 500 square ft of heating surface or 4,000lbs of steam per hour must have at least two. They must be capable of relieving all the steam at high fire with the pressure not exceeding 6% above MAWP. At least one SV must be set at or below the MAWP. Boilers with more than one SV can have one set up to 3% above MAWP. The lowest set SV cannot be more than 10% lower than the highest.

Front 52

Can you have an internal pipe connection on a safety valve?

Back 52

No, there can be no restriction to the inlet of a SV.

Front 53

What information is on a Safety Valve nameplate?

PVB DYNAMICS

Back 53

P Pressure Set

V “V” Stamp for safety valve

B Blowdown/Blowback pressure in psi

D Diameter/Size of Seat r in inches

Y Year built/code #, (may be part of Ser #)

N Name of Manufacturer or trademark

A ASME/NB stamp

M Model number

I Inches Lift

C Capacity in lbs/hr

S Serial number

Front 54

Give three ways to figure the relieving capacity of a safety valve.

Fuel, Accumulation, Evaporation capacity

FAcE

Back 54

Accumulation test, Maximum Evaporative Capacity test, and Maximum Amount of Fuel that can be Burned.

1. Accumulation test, with all steam outlets closed run boiler on high fire. Pressure must not rise 6% above MAWP

2. Maximum Evaporative Capacity test, with all steam outlets closed and boiler off run feed pump(s) continuously. Pressure must not exceed 6% of MAWP

3. Maximum Burnable Fuel , use ASME Section 1 Code, Appendix Table A-44, Minimum pounds of steam per hour per square foot of heating surface. Formula W=CxHx0.75/1100

W=Weight of steam generated per hour

C=Total weight or volume of fuel burned/hr at time of maximum forcing, lb or cu ft.

H=Heating value of fuel, Btu/lb for coal or oil, or Btu.cu ft if gas

0.75=Average boiler efficiency

1100=Average number of Btu in a lb of steam

Front 55

Describe the safety valve piping requirements for the following, Connection to boiler,Steam discharge line, and discharge drain line.

Back 55

The connection to the boiler must not have any intervening valves and there can be no restrictions to the SV inlet pipe.

The discharge piping must be fitted with a slipjoint and have free movement when either cold or hot. It must not place any strain on the valve. There can be no more than a 90° bend in the piping in total such as two 45° elbows. The area of the discharge pipe must be equal to or greater than the SV outlet or outlets in the aggregate. The drain line to the discharge cup must remove all condensing steam (minimum 1/2" pipe?) from the discharge without allowing it to build up around the SV.

Front 56

When two safety valves are mounted individually, what are the requirements for the smaller valve? When are two or more safety valves required

Back 56

When two safety valves are mounted individually the smaller valve must relieve at least 50% of the capacity of the larger valve. If two safety valves are connected by a Y pipe or a duplex safety valve is used then both valves must have equal relieving capacity. In total the safety valves must be able to relieve all the steam produced by the boiler at high fire without the pressure rising more than 6% above MAWP.

Two or more safety valves are required on boilers with 500 square feet or more of heating surface, or those exceeding 4,000lbs of steam production per hour. 500 x 8(lbs per sq ft fire tube boiler)=4000

Front 57

List safety valve requirements.

Back 57

Must relieve all pressure from the boiler at high fire without pressure exceeding 6% of MAWP. Must be spring-loaded pop type. Boilers over 500 sq ft heating surface or producing more than 4000lbs of steam an hour must have at least two. On boilers equipped with multiple SV at least one valve must be set to pop at or below the MAWP. No valves can be placed between the SV and the boiler. The inlet piping to the SV must be at least the same diameter of the SV inlet pipe.The highest set valve can be set 3% above MAWP and the lowest set valve can beset 10% below the highest, the remaining valves can be set in between the highest and lowest set valves. All Superheaters and Reheaters must be equipped with at least one SV. Superheater SVs must be set to blow before steam drum valves (usually 5% below). Superheater SVs cannot relieve more than 25% of the boiler’s steaming capacity; drum valves must remove at least 75%. Reheater SVs must be capable of relieving at least 15% of steam flow (Reheaters use low pressure steam from the Intermediate Turbine so are set at lower pressures, they protect the Reheater, not the boiler). On boilers equipped with two SVs with independent connections the smaller of the two valves must be able to relieve at least 50% of the capacity of the larger SV. Boilers equipped with duplex SVs or SVs connected to a Y pipe the relieving capacity must be equal between the two valves. SV discharge piping must be fitted with a slip joint and not connected directly to the SV, it cannot place any strain on the SV. Boilers operating at over 300psi must have flange-type connections. SVs for steam temps above 450F require special steel alloys.

Front 58

Describe the requirements of a superheater safety valve.

Back 58

A superheater SV cannot relieve more than 25% of boiler capacity. It must lift before the drum SV (usually set 5% lower than lowest drum valve) to insure steam flow to cool the superheater. It must be made of steel alloys for temperatures over 450°F.

Front 59

When ordering a safety valve what information must you supply the safety valve supplier?

Back 59

The MAWP of the boiler, the Steaming Capacity of the boiler in lbs per hour, the total number of SVs for the system, the inlet and outlet diameters of the valve, whether the valve is for the drum, DA, superheater, or Reheater, whether a flanged or threaded connection is used.

Front 60

The safety valve just blew, your pressure gauge says you’re at set pressure what do you do?

Back 60

Determine if the steam gauge is faulty. Check steam header gauge and boiler gauge to see if they both have the same pressure reading. If the boiler is equipped with more than one safety valve and others have tripped then the cause is probably high pressure. Lift and close the handle on the safety valve to see if it will seat. If it will not seat then if possible turn the fire low to allow the pressure to drop to a point where it does seat. If it still does not seat then secure the burners, isolate the boiler from the steam header, and continue to feed water into the boiler until it cools. When possible determine root cause for failure.

Front 61

How do you know when to close the main steam stop? The Header Valve?

Back 61

Closing the main steam stop valve would be in order if the boiler were going off-line for service, inspection, or some emergency, but itwould not be closed under normal circumstances.

Steam header valves are often connected to chain wheels to facilitate more frequent operation. Header valves to various processes would be closed when the boiler house is shut down to prevent steam from leaving the boiler if the boilers were shut down for weekends, etc. A main steam stop could be used for this purpose, but in general it’s a bad idea to put wear on the valve by frequent opening and closing.

Front 62

How do you know when to stop feeding water into a boiler?

Back 62

Under normal operating conditions the boiler should be fed water as needed to maintain the proper water level. If the boiler were shut down, cooled off to some extent, isolated, and had plenty of water in it then the feed water could be stopped. If the water level were below the gauge glass and only steam came from the bottom try cock it would be dangerous to put water in the boiler. It should be isolated and secured.

Front 63

Linear coefficient of expansion carbon steel

Back 63

.00000734 inches per degree F. (phone: five zero 734)

Front 64

Flue Gas Approximate CO2 for Coil, Oil, Gas

Back 64

Coal=16%-18% ,Oil, 12%-14%, Gas 10%-11%. (Tens, Tweens,Teens)

Front 65

What does excessive excess air do to CO2 readings and boiler efficiency?

Back 65

Excess Air decreases CO2 readings and lowers boiler efficiency by blowing heat out of the stack. CO2, Oxygen, and Excess Air are measured as a Percentage of the flue gas. CO2 is generated by the burned fuel. Increasing the excess air dilutes the percentage of CO2 in the flue gas mixture and increases the percentage of excess air and unused oxygen. Water Vapor is also a part of the flue gas, but it is not measured.

Front 66

Determine boiler efficiency using Bacharach Fyrite method.

Back 66

The Bacharach Fyrite is a form of the Orsat method of chemical analysis to determine the percentage of CO2 and O2 in the flue gas. This information and the stack temperature are used on a chart to determine boiler efficiency. Higher CO2 readings and lower stack temps indicate better efficiency. The efficiency is also dependent on the type of fuel burned, with coal having the highest efficiency, oil lower, and natural gas the lowest. There is a separate Fyrite test for O2, which is used to determine the amount of excess air.

Front 67

Describe how you would start a valve out motor centrifugal feed water pump?

Back 67

Make sure the pump is primed, the input valve is open, and the discharge valve is closed or nearly closed. Turn the pump on and slowly open the discharge valve.

(The discharge valve is closed at start up to reduce load on the motor as it comes up to speed)

Front 68

What limits the capacity of a centrifugal pump? Give at least 3 examples.

Back 68

The capacity is limited by Cavitation, Horsepower, Suction head, Water Temperature discharge head. The pump could also be restricted by Lost Prime, blockages such as a stuck check valve, dirty strainer, or by chemicals that could cause foaming in the pump. There could also be mechanical issues in the pump such as an impeller that is eroded from cavitation or otherwise damaged. There could also be wear between the Wear Rings on the Impeller and Volute.

Cavitation is when vapor bubbles form and collapse on the impeller of a centrifugal pump. It is caused by high water temperature, lowsuction head, or a restriction in the suction line.

Horsepower is important because centrifugal pumps are designed on a Pump Curve to operate in a fairly narrow range of Total Dynamic Head, so an underpowered pump will not be able to overcome Static Pressure.

Suction Head, Low suction head could be caused by a faulty switch leading to a low level in a tank, thus the pump would keep running draining the tank and line beyond the minimum Net Positive Suction Head.

Water Temperature is important because boiling point corresponds to pressure causing flash steam in the impeller and cavitation. Condensate Traps which are stuck open return steam with condensate which can lead excessive temperatures in DA or condensate receiving tanks.

Front 69

What is the formula for the horsepower for a centrifugal pump

Back 69

hp= Q x 8.33 x H x Sp. Gr / 33,000 x Ep

Q = quantity in GPM

8.33 = weight of one gallon of water

H =head

Sp. Gr. – specific gravity (water is 1)

33,000 = ft lbs/min in 1hp

Ep = efficiency of pump

Front 70

What is the approximate calculation used to find out how many gallons are pumped in a minute?

(assumed positive displacement piston pump)

LANE/231

Back 70

Q= L x A x N x Ep / 231

Q = quantity

L= length of stroke in inches

A= area of piston in sq in

N = number of strokes

Ep =Efficiency of pump

231 = 231 cu in in one gallon

On a Duplex Pump the efficiency would be affected by the percentage of lost motion

Front 71

Why is there a relief valve on the discharge side of a positive displacement pump?

Back 71

To prevent damage to the pump. The relief valve opens and recirculates the fluid to protect the pump from over pressure should a valve be closed or some other blockage of the discharge occur.

Front 72

Describe the operation of a rotary pump.

Back 72

A rotary pump is a positive displacement type. It uses gears, cams, or veins to pump fluids. They are generally used for oil and other heavy fluids.

Front 73

What does “P” stand for in the hp equation?

Back 73

P stands for Mean Effective Pressure. PLAN/33,000 is the method of calculating the horsepower of a reciprocating engine, Pressure, Length, Area, Number. Mean effective pressure is determined by the inlet pressure times 40% for a simple engine, 50% for a condensing engine, and 70% for a compound engine calculated on the area of the high pressure piston.

Front 74

How does chapter 146 determine reciprocating engine horsepower? Section 48

Wikipedia has great animation

https://en.wikipedia.org/wiki/Steam_engine#/media/File:Steam_engine_in_action.gif

Back 74

Section 48 does not actually mention PLAN and misstatesthe formula as pounds rather than percent. I have seen this question asked. I will demonstrate the formula.

Front 75

How to calculate reciprocating engine horsepower. Science of Successful Threshing. 1915, Pg. 86-87

Back 75

P.L.A.N. dividedby 33,000 {33,000 is ft lbs/min in 1 hp}

P=Pressure constant {find mean effective pressure, which is the inputpressure times the conversion factor below}

Input pressure times…

40% for a simple engine.

50% for a condensing engine.

70% for a compound engine, calculated upon the area of the highpressure piston. {A compound engine has at leastone low pressure piston}

L= Length, of stroke in FEET

A=Area in square inches of the face ofthe piston

N=Number of power strokes per minute, RPM,x 2 if double acting (almost all steam engines are double acting)

Ex. Double acting condensingengine, 9" bore, 10" stroke, 250 rpm, boiler pressure 150lbs {50hprated J.I. Case engine}

P= 150psi x 50% (Condensing engine 50% of150psi boiler pressure) = 75lbsMean Effective Pressure MEP

L= 10” / 12= .833 (travel ofpiston in feet)

A= D2 x .7854, 9” bore, 9 x 9 = 81, 81 x .7854 = 63.617 sq. in. (area of piston insquare inches.)

N = 250 RPMx 2 = 500 Power Strokes per minute (double acting)

P=75 MEP x L=.833 x A=63.617 sq in x N= 500 = 1,987,236, 1,987,236/33,000 (ft lbs/min in 1hp) =60.2 hp

PLAN is a measure of Indicated Horsepower (ihp). It does nottake into account engine friction losses.

Brake Horsepower (bhp), delivered by engine’s shaft, take off 10% forfriction, 60.2 x 90% = 54.18, 54 Brake Horsepower

Front 76

How do you determine the tube sheet is tight against a rolled tube in a surface condenser?

Back 76

Mill Scale Cracking, a slight wrinkled appearance in the metal of the tube after rolling. Tubes can be secured by rolling and flaring both ends, rolling one end and packing on the other end. They can also be secured by rolling and flaring, packing fiber, metal rings and a ferule, or by welding.

Front 77

What is single sheer on a rivet? What is double sheer?

Back 77

Single sheer refers to the sheering of a rivet’s shank on a riveted lap joint or a single strap butt joint where two plates of metal are riveted together. Double Sheer occurs on a double strap butt joint where three plates of metal are riveted together causing the rivet to be sheered at two points.

Front 78

Start up a small impulse turbine? Be complete and list every step.

Back 78

Read and follow the manufacturer’s instructions.

Open the turbine drains and traps.

Check lubrication cups/lube oil system.

Make sure steam discharge valve is open.

Crack open steam supply valve and then open enough to get turbine spinning, then cut back on steam flow.

Once turbine is spinning test the over speed trip at about 300rpm.

Close steam supply valve and reset over speed trip.

Crack open steam supply valve and throttle enough to get turbine spinning again then maintain rotation, but cut back on flow as turbine warms up.

Listen for rubs and noises, excessive vibration; make sure lube system works properly.

Close drains when there is ample steam flow and condensate has drained from steam chest.

Fully open the steam supply valve once turbine has warmed fully.

Front 79

Why are large pressure drops required in Curtis Stages?

Back 79

To change heat energy into mechanical energy very quickly. This method allows steam to obtain greater velocity/kinetic energy by expanding rapidly in the fixed stages. Curtis turbines are impulse velocity compounding turbines in which the kinetic energy of the steam impacts the blades of the turbine. Most large high pressure reaction turbines are Composite Turbines with two or more Curtis stages as the first section of the turbine.

Front 80

What type of staging is used in a terry turbine?

Back 80

Velocity staging. A Terry turbine, also known as a Reentry Turbine, is an Impulse velocity compounding turbine. It uses a single disc with bucket type blades in the outer perimeter. High pressure steam enters one portion of the disc and is redirected at other sections in progressive stages and lower pressures.

Front 81

Minimum and maximum blowdown pipe sizes.

Back 81

1” Minimum, 2 ½” Maximum, ¾” minimum for boilers less than 100 sq ft heating surface.

Front 82

Name 5 most common steam traps.

Back 82

Inverted Bucket, Thermodynamic (disc-type), Thermostatic, Float and Thermostatic F&T. Orifice, Impulse

Front 83

What does fail-open mean, and where would you find two examples.

Back 83

Fail open refers to valves being designed so that they open fully if the operating medium such as air, hydraulics, or electricity is lost. A feedwater regulating valve, a Makeup feed valve, a steam admission valve to a turbine driven feed pump would all fail open.

Front 84

How do you control a superheater?

Back 84

Superheat temperature can be controlled by the use of a Desuperheater, which is a pipe that runs through the steam drum, an Atemperator, which injects water to cool the steam, and by the use of Baffles which can deflect heat away from the superheater.

Front 85

What is the relief valve for on a condensing turbine?

Back 85

A relief valve protects the turbine casing from damage due to over pressurization.

Front 86

Identify this picture, name its components.

Back 86

Front 87

Draw a picture of a PRV valve in detail. Spring loaded direct acting pressure regulating valve.

Back 87

Front 88

What are the two balance forces in a direct acting Pressure Reducing Valve? Sketch the balance forces.

Back 88

Spring Tension and Outlet Pressure are the balance forces.

The spring pushes down on the diaphragm while downstream pressure pushes up on it. A shaft on the bottom of the diaphragm connects to the steam inlet valve (usually a ball bearing). When the downstream pressure is low the spring forces the top of diaphragm down opening the inlet valve. As downstream pressure increases it pushes up on the bottom of the diaphragm and throttling or closing the valve. The downstream pressure can be increased by tightening the bolt on top or decreased by loosening it.

Front 89

What are the specific ASME codes which pertain to: Piping Repairs, Welding, Etc.?

Back 89

All persons installing or repairing pressure vessels, refrigeration equipment, and sprinkler systems must be certified and licensed in Massachusetts. Pressure piping requires the Pp stamp and applies to steam, refrigeration, gas, etc. Non-Certified employees of a company are allowed to perform piping repairs to company property on the facility or on location. Welders must be certified and are required to have the R stamp to weld apressure vessel.

There are various levels to piping and refrigeration trades. Apprentice is someone who is licensed to work as an employee under the direct supervision of a Journeyman or Master. Journeyman is someone who is allowed to work unsupervised and can work for themselves, but cannot hire others. Master is someone who is allowed to hire and supervise others in the trade.

Front 90

Name 3 ways to test a weld

Back 90

Hydrostatic Test, Magnetic Particle, Ultrasonic Wave, Radiograph, Dye Penetrant, Eddy Currents

Front 91

Perform a hydro test on a boiler.

Back 91

Remove or gag the safety valves, fill the boiler to the top of the vent with water between 70 and 120°F, close gauge glass isolation valves, close the vent and increase pressure to 1 ½ times MAWP. Lower pressure to MAWP before inspecting for leaks. Follow the inspector's instructions.

Front 92

Your chief engineer tells you the inspector is coming in 2 days prepare the boiler for an internal inspection.

Back 92

1. The boiler should already be cool.

2. Lock out tag out boiler, close header isolation valves and open free blow drain.

3. Open boiler and clean all soot and debris from fire side.

4. Drain and flush boiler thoroughly.

5. Remove handhole plates and manhole cover.

6. Remove float chamber, alternative low water cutout, remove cross plugs and end caps.

7. Expose inspectors stamp on shell.

Front 93

What procedures would you take when taking a boiler off line and opening the boiler for inspection?

Back 93

Shutdown boiler and fill with water to about one inch from top of water glass, Shut all Power off, close fuel, water, and steam valves, Open free-blow drain between main steam stop and non-return valves for multiple boilers on a common header, Lock-Out-Tag-Out boiler, Open Drum Vent to prevent vacuum. After boiler has no pressure and has cooled open fire side of boiler, clean out all tubes, get a Confined Space Permit and Attendant to enter and clean thoroughly. Once fire side is cleaned remove manhole cover and drain and flush water side, leave any baked on oil inside the boiler for inspector to examine, remove hand-hole plates, remove cross-plugs and end-caps to water column and controls, remove float chamber, expose inspector’s stamp on shell. If entering water side perform confined space. Call inspector for appointment.

Front 94

Name 2 ways to determine the heating value of fuel oil and fully describe one ofthem.

Back 94

Bomb Calorimeter: This is the only device that I have been able to confirm as being used for fuel oil. Uses a stainless steel cup to heat a known quantity of fuel. The fuel is electrically ignited. The burning fuel heats water. The temperature is recorded before and after to determine the heating value.

Reaction Calorimeters: There are numerous other calorimeters such as the Heat Balance Calorimeter. The devices may vary, but the principle is the same, burning a specific amount of fuel to determine the rise in temperature.

Other tests: Fuel oil is also tested for carbon, hydrogen, sulfur, nitrogen, and ash content, all of which affect its heating value.

Front 95

How do you determine the Btu value of fuel? A. open cup, B. calorimeter, C.hydrometer, D. viscometer

Back 95

A bomb calorimeter is used to determine the Btu content of liquid fuels. An opencup is used to determine the flash point, a hydrometer is used to determine the specific gravity, a viscometer is used to determine the fuel’s ability to flow, viscosity is measured in Saybolt Seconds Universal SSU.

Front 96

What is the temperature for the dew point of flue gases and what effect does it have?

Back 96

120°F is considered the Dew Point for Flue Gas, though it depends upon atmosphericconditions. The dew point is the point at which Sulfur Dioxide forms sulfuric acid and some flue gases condense into liquid. Normally Stack Temp should not go below 180°F to prevent condensation. Condensation makes soot sticky and activates corrosive agents when water mixes with soot on economizers, air preheaters, and stacks. The most corrosive agent in flue gas is SO2, sulfur dioxide. This can form sulfuric acid. It corrodes stacks, air pre-heaters, and sometimes economizers.

Front 97

Which of the following affect combustion at the burner?

A. Viscosity
B. Pour Point
C. Fire Point
D. Flash Point

Back 97

Fire Point is the only factor that would affect the combustion directly at the burner. It is the temperature needed for a fuel to ignite and continue to burn. For #6 it’s 700°F. A cold boiler can affect the oil’s ability to continue to burn.

Viscosity is important because heavy fuels like #6 need to be heated to flow. Lower temps cause fuel to be more viscous. Pour point is the minimum temperature required for the fuel to flow, for #6 it’s 90°F. Flash Point is where the fuel will ignite with a pop, but not continue to burn around 150°F for #6.

Front 98

How do you start a high pressure boiler firing #6 fuel oil?

Back 98

Turn on oil pump and oil heaters to circulate and warm oil, reset low oil pressure trip device if necessary. Close main gas valves to burner for safety. Set selector switch to oil. Insert oil burner nozzle and lock in place. As oil warms turn the handle on the boiler’s oil strainer. Check the true water level before attempting to start boiler. Once oil temperature to burner nozzle is above 180° start boiler. Mark on smoke chart roll time switched to #6.

Front 99

Describe an air preheater to me? The type, efficiency, and where they located what they do.

Back 99

There are two types of air preheaters, tubular and regenerative.Both types of air preheaters are located after the economizer and before the stack.

A tubular preheater heats combustion air by circulating flue gases on the outside of the tubes with fresh air inside the tubes.

A regenerative air preheater has a rotating heating element that absorbs heat from the flue gas and transfers it to the incoming combustion air.

Preheating the air results in about 1% efficiency for every 40°F (according to state 1% per 40°F, in reality it’s 1% per 100°F)

Front 100

What is caustic embrittlement and what causes it?

Back 100

Caustic Embrittlement/ Caustic Cracking is a condition that occurs below the water level in boilers where carbon steel becomes brittle, cracks, and suddenly fails. Under high heat and alkalinity hydrogen forms bonds with the carbon in the steel causing it to become brittle.

It occurs in high stress areas such as rivets and joints where there are small crevices which cause an accumulation of caustic agents due to the steaming off of the boiler water. It has been associated with the Lime Soda process of water demineralization. Excessive pH levels in boiler water can worsen this problem. Note: This was a serious problem on HRT boilers when the metals weren't very good, they had riveted seams, constant heat on the seams, and very poor water treatment. They could explode without warning. Look up Grover Shoe Factory disaster.

Front 101

What is electrolysis?

Back 101

Electrolysis is Galvanic Corrosion that occurs any time two dissimilar metals are in contact in the presence of an electrolyte. In boilers copper in pipes and fittings can result in electrolysis. Magnetite is included in boiler treatment chemicals to help alleviate galvanic corrosion.

Front 102

Describe two methods to find the composition of fuel.

Back 102

Proximate Analysis and Ultimate Analysis, they are used to find the composition of coal. Proximate Analysis, Determines coal % of moisture, volatile matter, fixed carbon, ash, sometimes sulfur. Ultimate Analysis is a Lab test to determine coal % of Nitrogen, Oxygen, Carbon, Ash, Sulfur, Hydrogen (NO-CASH)

Front 103

What temperatures are we concerned with when it comes to turbine lube oil?

Back 103

Inlet Minimum 90°F, Outlet Maximum 180°F, no more than 50°F temperature differential across the bearing. Normal inlet temp is 120°F

Front 104

In relationship to heat exchangers what is fluid filming? Is it desirable or undesirable? Would you increase it or decrease it?

Back 104

Fluid filming is the tendency of a fluid to cling to a metal surface. This tends to inhibit heat transfer.

Fluid filming is undesirable.

Heat exchangers are designed to decrease fluidfilming by increasing turbulence to flow.

Front 105

What are 5 causes of low vacuum in a turbine?

Back 105

Plugged Tube Inlets, Scale build-up in Tubes, Faulty Steam Jet Air Ejector, Faulty Vacuum Pump, Air Leaks, Clogged Traveling Screen, High Hot well, Air Blanketing Water Box side of Upper Tubes, Faulty Circulating Water Pump, Faulty Condensate Pump, Cooling Water High Temperature, Pressure Relief Valve stuck open.

Front 106

Give 3 reasons for rising backpressure in a surface condenser. (just worded a little differently than the question above)

Back 106

Air infiltration, Clogged Tubes, Cooling water flow/temperature, High hot well, Non-condensable gases blanketing upper tubes, Malfunctioning Steam Air Jet ejector, etc.

Front 107

How many Engineers does it take to change a light bulb???

Back 107

Two, one to lock and tag it out and another to call the electrician! Ha-ha!

You've already made it past 100 questions!

Front 108

List 5 important turbine auxiliaries and their functions

Back 108

Gland Seal Steam System, Gland Seal Steam Condenser, Turning Gear, Speed Limiting Governor, Over Speed Trip governor, Lube Oil System, Low Lube Oil Pressure Trip, Throttle Valve, Sentinel Valve, Thrust Bearings, Vibration Trip Sensors, Expansion and Contraction sensors, Main Steam Stop Valve, Ventilator/Dump Valve, Emergency Blowdown Valve, Pressure Gauges, Thermometers, Thermocouples, Sight Glasses

Gland Seal Steam-prevents vacuum in turbine seals, used on startup

Gland Seal Steam Condenser- Condenses steam from the gland seals, valves, and other steam appurtenances to the turbine.

Turning Gear- eliminates Rotor Eccentricity by turning it on startup to prevent Gravity Bow, and on shutdown to prevent Thermal Bow

Over Speed Trip Governor-Trips turbine if speed exceeds 110% of rated capacity

Lube Oil System-Provides lube oil which lubricates and cools the bearings, is used to maintain axial clearance in thrust bearings, and may provide the medium for hydraulic devices such as the throttling governor on some turbines

Front 109

How many governors do you need to operate a turbine?

Back 109

There must be 2 governors, an Operating Governor, and an Emergency Governor. The operating governor throttles the rate of steam flow based on the load to maintain a constant speed. The emergency governor is often called an over-speed trip. It shuts the turbine down if it accelerates to 110% or more of its normal operating speed. Governors work by centrifugal force.

Front 110

A. A common unit of work in the US is the foot-pound. A. Define a foot-pound.

B. How many foot-pounds are in one horsepower?

Back 110

A. A foot pound is the energy required to lift one pound one vertical foot.

B. One horsepower equals 33,000 foot pounds per minute.

Front 111

Describe how to take leads on a large main bearing.

Back 111

Measurements on a Journal Bearing can be taken with a Depth Gage Micrometer or Bridge Gage.

Depth Gage Micrometer-This device has a rod that fits through a cap on the top of the Journal Bearing. The top bearing has a hole for the rod to fit through. A measurement can then be taken to determine the depth between the upper part of the bearing and the rotor shaft. The wear can then be determined by comparing the measurement to when the bearing was installed. This device can only measure the bearing’s Vertical Clearance. The advantage with this method is that it works on all bearings.

Bridge Gage-This device mounts over the rotor shaft and is size specific to each bearing. It allows the use of Feeler Gauges to determine both the Vertical and Lateral bearing Clearance.

Front 112

What does the term LOAD mean with regard to metals?

Back 112

Load is metal deformation due to stress. Metal is said to be loaded when its shape has been distorted. A bag in a boiler would be an example of metal that is loaded.

Front 113

Describe the construction and operation of a single tube lifting injector.

Back 113

A lifting injector has a nozzle that sprays into convergent and divergent cones.The working fluid is usually steam, but could be compressed air or pressurized water if steam is not available. The jet of steam exiting the nozzle creates a Venturi effect which draws water up through the inlet. The velocity of the steam transforms kinetic energy into pressure as it passes through the two cones.

Front 114

What material are condenser tubes made of: If fresh water passes through them? If salt water passes through them?

Back 114

When fresh water is used for cooling Surface Condenser tubes are made of admiralty metal, which is a form of brass. When salt water is used the tubes are made of aluminum alloys, stainless steel, or titanium.

Front 115

What is grooving in a boiler?

Back 115

Grooving or channeling refers to condensate lines. It’s carbonic acid etching where the condensate comes in contact with the pipe.

Front 116

A 100 psi boiler is operating with 300F stack temps, is this boiler operating properly?

Back 116

No, the flue gas temp should be around 330°F or more depending upon load and type of fuel.

Front 117

What contributes to the quantity of water pumped by a centrifugal pump? Name at least three.

Back 117

The horsepower of the pump, the NPSH, net positive suction head, temperature of water being pumped, height of discharge head, bends or other restrictions in the discharge piping.

Front 118

Are you still reading these cards???

Back 118

Wow! You must be dedicated! :)

Front 119

What is a simple test for corrosives?

Back 119

A pH test, can be for Caustic in the boiler water, or Amine in the Condensate, also a Sulfite Residual test for oxygen scavenger.

Front 120

What is a quick way to find heating surface of a boiler?

Back 120

It is required to be listed on the manufacturer’s stamp on the boiler drum. The normal method is to add up all the flue gas side of the heating surface area with water on one side and flue gas on the other.

Front 121

Calculate heating surface of a tube 14' long 5' wide?

Back 121

5x3.14=15.7,14x12=168, 15.7x168=2637.6, 2637.6/144=18.32 sq ft

Front 122

What do you take into consideration when calculating heating surface for water tube boilers? Fire tube boilers?

Back 122

Heating surface is the area of a boiler with flue gases on one side and water on the other. Heating surface is calculated on the side receiving the heat. This is the outside of the tubes for water tube boilers and the inside of the tubes for fire tube boilers. For water tube boilers ½ the area of the water/steam drum and the entire mud drum area have water and need to be calculated minus the area of the tube holes. For boilers equipped with waterwalls the heat side must be calculated in. For fire tube boilers the area of the tube sheets needs to be calculated up the area of the NOWL minus the area of the tube holes. For Scotch Marine boilers the area of the furnace tube needs to be calculated as well. For HRT boilers 2/3 of the boiler shell up to the Closing In Line area is calculated.

Front 123

What are the impurities in coal?

Back 123

Sulfur, Nitrogen, Moisture, Ash (minor, iron forms clinkers, trace metals)

Front 124

How do you know a governor has taken over when operating a turbine?

Back 124

When the steam admission valve opens easily, it indicates equal pressure on both sides of the valve.

Front 125

16 is the cube of what number?

Back 125

4096,16x16x16=4096

Front 126

What is the cube of 64?

Back 126

4,4x4x4=64

Front 127

Explain how you would plug a tube in a water tube boiler? In a fire tubeboiler?

Back 127

By hammering in tapered tube plugs. Plugs are inserted on both ends of the tube. On a fire tube boiler they are inserted on the fire side, on a water tubeboiler they are inserted on the water side. Before inserting the plug the area must be thoroughly cleaned. It is also important to make sure the tube is not cracked at the tube sheet, in which case plugging would not help. The leaking tube should be punctured so that it does not build up pressure. As a generalrule up to 10% of boiler tubes can be plugged before replacement is necessary. On a fire tube boiler it is important to leave the tube in place because the tube acts as a stay to the tube sheet, for this reason it is important to limit the number of adjacent tubes that are plugged on a fire tube boiler. Plugging tubes should be used as a temporary measure only until proper repairs can be made.

Front 128

What is a turbine pump?

Back 128

A turbine pump is a centrifugal pump with multiple stages which allows for very high pressures. The high pressure side of one stage discharges into the low pressure side of the next stage. They are often used on boiler feed pumps

Front 129

What would be placed in the inter condenser drain loop to check that the valve is sealed properly when the ejector is in service?

Back 129

Water, the loop seal would be filled with water.

Front 130

There are 2 reciprocating pumps, one is low pressure and one is high pressure. How can you tell the difference and the rating?

Back 130

On a duplex pump the numbers are in sequence and refer to the driving piston,fluid piston, and stroke in inches. Thus 4 x 3 x 10 would be a 4” steam pistonwith a 3” water piston. The pump with the higher ratio steam piston areacompared to water piston area would be capable of greater pressures.

Front 131

Name 5 steam traps

Back 131

Inverted Bucket, Thermostatic, Thermodynamic, Float & Thermostatic, Impulse, Orifice

Front 132

What are the constituents of air? By volume and by weight.

Back 132

By Volume: 21% oxygen (20.91), & 79% nitrogen (78.09, and close to 1% argon another inert gas).

By Weight: 23.15% Oxygen, 76.85% Nitrogen

Front 133

What do the following symbols stand for: C - CO - H2O - SO2 - H2SO4

Back 133

Carbon, Carbon Monoxide, Water, Sulfur Dioxide, Sulfuric Acid

Front 134

Lube oil has 3 uses what are they?

And, what are 2 critical temperatures you should be aware when using Babbitt bearings?

Back 134

Lube oil prevents friction, carries away heat, and can be the hydraulic medium for some devices such as the governor valve on someturbines.

The inlet temperature and the outlet temperature across the bearing are the 2 critical temperatures. Oil from the lube oil cooler to the bearing inlet is normally 110°F-120°F and cannot be less than 90°F. It should increase no more than 50°F across the bearing with 180°F the maximum allowable outlet temperature.

Front 135

Name 3 methods of keeping steam from escaping from the turbine to the atmosphere

Back 135

Labyrinth Rings and Seals, Carbon Seals with garter springs, Water Seals

Front 136

When are two blowdowns required?

Back 136

Two blowdown valves are required at pressures 100psi or higher.

Most high pressure boilers are also equipped with a surfaceblow that removes impurities from the surface of the boiler water.

Two blowdown lines are needed on boilers with multiple mud drums such as an A-Type boiler. Two blowdown lines are also needed on horizontal firetube boilers that are not pitched to remove accumulations in the front and rear of the steam/water drum.

Front 137

What is a blow down tank used for? Is it used for intermediate or constant blow down?

Back 137

A blowdown tank is used to cool blowdown water from the boilers. It is used primarily for bottom blowdown. They can be used for constant surface blowdown, but blowdown tanks do not recover heat or water as does a flash tank.

Front 138

How do you blow down a boiler with a quick opening valve, slow opening valve and you cannot see the gauge glass?

Back 138

1. Call an assistant to watch the water level in the gauge glass

2. Find the true water level by blowing down the gauge glass with each gauge glass valve closed independently

3. Have at least ½ a water level or more in the gauge glass

4. Open cooling water to the blowdown tank

5. Open quick opening valve

6. Open slow opening valve wide and close it quickly

7. Close the quick opening valve

8. Check the water column gauge glass level

9. Secure cooling water to the blowdown tank

Front 139

What are the piping requirements for a Blowdown Tank?

Back 139

Heavy Duty piping is required at pressures above 125psi.

Front 140

What is the primary difference between a gate valve and a globe valve?

Back 140

A gate valve is not designed for throttling, it should be used only in the fully closed or fully open position. A globe valve can be used for throttling theflow.

Front 141

What are the advantages of water tube compared to fire tube boilers?

Back 141

Watertube boilers can be built to unlimited heating capacity, they operate at very high temperatures and pressures, they can be fitted with superheaters, they are much safer, and they can burn solid fuels including trash and biomass

Front 142

What is cold stacking and what affect does it have on the stack & breeching when you have an air preheater & economizer?

Back 142

A cold stack would lead to cold end corrosion. When the flue gas temperature falls below the dewpoint, usually around 120°F, it causes water vapor and sulfuric acid in the flue gas to form droplets on the stack and air preheater. If cold enough, droplets could form on the economizer and possibly the breaching. This would corrode the metals in these components if the condition lasted long enough.

Front 143

How do you know when a throttle operated steam turbine is safe to operate?

Back 143

By testing the over speed trip device, then restart the turbine and slowly open the steam inlet valve until opens easily. This indicates that the pressure is balanced on both sides and the throttling governor has taken over.

Front 144

How would you know a shaft governed engine is safe to operate?

Back 144

By testing the over-speed trip device for a turbine. For a reciprocating steam engine by opening the steam in let slowly to make sure the throttling governor was controlling the speed. (I included this, though I suspect someone did not remember the question properly. An engine refers to a reciprocating engine, not a turbine.)

Front 145

What are three ways to figure boiler horsepower according to Chapter146?

Back 145

Chapter 146 Section 48 lists 4 methods to determine boiler horsepower.

1. Use manufacturer’s tag (if available).

2. Steam output steam output on manufacturer’s tag (lbs/hour) divided by 34.5.

3. BTU/hour input on manufacturer’s tag divided by 41,840.

4. BTU/hour output divided by 33,475.

Front 146

What is on the stampings of a power boiler?

Back 146

S for power boiler, NB for National Board, Manufacturer, Serial Number, Heating Surface, MAWP,

Front 147

Why do we preheat boiler feed water?

Back 147

Boiler feedwater is preheated to avoid thermal shock to the boiler. An open feedwater heater, DA, also removes most oxygen and other non-condensable gases. Feedwater is also heated with waste heat from blowdown, with economizers, and injectors so that sensible heat is not otherwise lost.

Front 148

(MC) What is the purpose of the steam control valve on a DA?

Back 148

Thecontrol valve injects steam into the DA at 5-10 psi to mix steam with in comingfeed water to remove non-condensable gases.

Front 149

Which uses more oil a high pressure boiler or a low pressure boiler?

Back 149

A high pressure boiler uses more oil or other fuel because temperature corresponds to pressure. Higher pressures require higher temperatures to transform water into steam which requires more fuel.

Front 150

List 7 limiting controls in a combustion control system

Back 150

Low Water Cut-Out, Alternative Low Water Cut-Out, Flame Failure Detector, AirProving Switch, Low Oil Pressure Switch, Low Oil Temperature Switch, Oil Valve Proof of Closure Switch, Low Gas Pressure Switch, Gas Valves Proof of Closure Switches,

Front 151

What is the function of water flingers found near the packing of the stuffing box of a centrifugal pump?

Back 151

Oil flingers and slingers are discs that pick up oil in a reservoir of a centrifugal pump to keep the bearings lubricated. They are part of a bottle-fed lubrication system. Flingers splash the oil around and provide better lubrication than do slingers depending on the pump. I am unaware of a water flinger.

Front 152

Explain in detail Net Positive Suction Head required and Net Positive Suction Head available.

Back 152

NPSH required is the pump manufacture’s pressure head requirement for preventing cavitation of the pump. Available NPSH is measured from the center of the inlet to the height of water head required. Bends in the pipe and other flowrestrictions need to be taken into consideration.

Front 153

Btu content of:

1lb of #6 Fuel Oil

1lb of Coal

1 cu ft of Natural Gas

Back 153

#6 =17,780 Btu/lb, also 152,000 Btu per gallon (Answer on exam was 19,000, 17,780 is the actual figure commonly used)

Coal = 14,000 Btu/lb

Natural Gas = 1,080 Btu/cu ft

Front 154

What is the BTU content in #5 fuel oil? (this came from a 2nd fireman test, I don’t think it was remembered properly)

Back 154

One gallon #5-148,000 Btu. #1-136,000, #2-138,500, #3-141,000, #6-152,000. Coal 1lb-14,000, Natural Gas cu ft- 1,075 Specific numbers vary depending on source.

Front 155

How can you tell a tube is tight against the hole in the tube sheet when expanding the tube

Back 155

Mill Scale Cracking on area of the tube that is compressed into the tube sheet. This is a slight flaky appearance of the metal from the compressive stress of the tube roller. A hydrostatic test should be performed after to verify all tubes are sealed.

Front 156

What causes electrolyte action in boiler water

Back 156

Impurities dissolved in boiler water form negatively and positively charged ions known as electrolytes.

Front 157

What 2 temperatures are of concern for Babbitt bearings

Back 157

The Lube Oil inlet temperature from the oil cooler and the outlet temperature from the bearing. The inlet temperature must be a minimum of 90°F. The outlet temperature cannot exceed 180°F. The ideal range for the inlet temperature is110-120°F, and there should be no more than a 50°F rise in temperature across the bearing.

Front 158

What causes sparks in an oil fired boiler, give three examples

Back 158

Water in the fuel oil, Atomizing Steam too cold, Incomplete combustion due to inefficient atomization, (Impurities in Fuel, Oil too cold)

Front 159

Are there more than one type of fusible plug? If so explain.

Back 159

There are 2 types, Fire-Actuated and Steam-Actuated. A Fire Actuated fusible plug is located just above the lowest permissible water level.It melts at around 450°F. It has combustion gases on one side and water in the drum on the other. If the water level drops below the plug the metal alloys in the plug melt and steam comes out creating a loud whistling noise.

A Steam Actuated fusible plug has a lowermelting point than the fire actuated fusible plug. It is connected to a pipe connected to the drum just above the lowest permissible water level. The pipe is filled with cool water. When the level in the drum drops too low the water drains out of the pipe exposing the plug to steam which melts it creating aloud whistle. There is normally a valve on the pipe so the fusible plug can be replaced without shutting down the boiler.

Front 160

Name 3 causes of a BAG in a fire tube boiler?

Back 160

Scale, Sludge, and Oil are the most common causes of a bag in a boiler. A bag is a deep bulge in the bottom of a HRT boiler’s shell caused by overheating due to improper heat transfer. Other causes have been mud and sand and objects dropped into the boiler during maintenance. It was more common in years past before modern water treatment methods. Oil was a problem for boilers with steam engines.

Front 161

Note: About Heating System and 1st Fireman’s Exam.

Back 161

A 1st Fireman’s license allows someone to be in charge of an unlimited number and capacity of boilers up to 25psi. This is typically the license needed to be incharge of a heating system of a large building. A 3rd engineer can be in charge of high pressure, but not unlimited capacity even at low pressure.Thus a 1st Fireman could be in charge of a school that had two 25psi 300hp boilers on a common header, but a 3rd Engineer could not. The 1stFireman’s exam often has plenty of heating system questions because many large buildings use steam boilers for heating. The 1st Fireman and 3rd Engineer licenses are tailored for different purposes.

Front 162

Describe two heating systems?

Back 162

One-Pipe,Two-Pipe, (one-pipe and two- pipe is the correct answer), Hydronic, Forced Hot Water. Hydronic circulates hot water through tubes in the flooring, but some systems also include baseboards. Forced Hot Water circulates hot water through baseboards.

Front 163

Explain a single pipe heating system

Back 163

One-Pipe system, Steam and condensate both use the same pipe. Steam and Condensate enter the bottom of the radiator. There is a thermostatic air vent on the opposite side. The vent opens and vents the air as the system starts up. When steam hits the vent it closes and steam condenses in the radiator. When the radiator cools the vent opens and allows the condensate in the radiator to return the boiler by gravity. This type of system uses a Hartford Loop. A One-Pipe system has a lot of issues, most notably water hammer, corrosion from air being continuously allowed in the system, and the vent getting plugged with rust. It is also very important that the radiators be pitched towards the pipe to allow condensate to drain. A one pipe system is also very inefficient because condensate travels down the pipe as steam rises up, thus the condensate is condensing steam and greatly contributing to water hammer as steam vapor bubbles collapse. This type of system was necessary before electricity when burning coal or wood because the heat to the boiler was not controlled automatically.

Front 164

Explain a two-pipe heating system

Back 164

Two-PipeSystem, Steam and Condensate have separate pipes. This system has a steam line that enters the top of the radiator and a condensate return line at the bottom. Most systems also use a condensate pump to create vacuum which increases steam flow. There is a Thermostatic steam trap connected to the condensate end of the radiator. This type of system costs more to install, but has fewer maintenance issues, less rust from air entering the system, and less water hammer.

Front 165

Why would you use a vacuum pump in a heating system?

Back 165

Condensate pumps are on most Two-Pipe systems. They create vacuum in the condensate return which creates greater pressure differential between the steam pressure and condensate lines. This allows for smaller size piping, valves, and fittings, less water hammer, lower pressure steam on the boiler, and more efficient heating, particularly at the end of the system on large buildings. They are fitted with a vent to remove air in the system.

Front 166

List four reasons why a radiator would fail to heat up properly?

Back 166

Sludge and dirt in the radiator could cause loss of heat transfer. On a one-pipe system the air vent could be plugged. Also on a one-pipe system the pitch of the radiator could be angled away from the steam valve causing condensate to stay behind in the radiator. This could cause water hammer and it would lead to less effective heating.

On a two-pipe system the steam trap could be stuck closed which would back up condensate into the radiator. Also the condensate pump could fail which would cause a back-up in the system.

Front 167

Does a cast iron boiler need a bottom blow down? If so, what is the minimum size?

Back 167

Yes,they need a bottom blowdowns. The minimum pipe size is 1”OD, unless the boiler has 100 sq ft or less of heating surface, then it can be 3/4".

Front 168

What would prevent a steam radiator from heating up properly?

Back 168

Air trapped in the radiator, air bound. The thermostatic vent may be broken or plugged.

Front 169

BLEVE (general knowledge not on test)

Back 169

Boiling Liquid Expansive Vapor Explosion. Improperly maintained heating boilers and hot water heaters can lead to serious explosions destroying large buildings often with loss of life. Look this up for pictures. Heating boilers need to be properly maintained.

Front 170

Draw and explain a Hartford Loop

Back 170

A Hartford Loop is a form of Loop Seal that acts as a safety device for steam heating systems. It uses a flooded section of pipe (wet return), which is connected just below the gauge glass and extends 2” above the boiler’s low water level. It allows for gravity return of condensate without the need for a check valve. It prevents the boiler from draining itself should the condensate return pipe leak. A Close Nipple is a section of pipe about 2” that connects the condensate line to the Hartford Loop, it is short to prevent water hammer from steam condensing in the pipe. It was first developed in 1919 by the Hartford Insurance Company for use on coal and wood fired boilers. The first low water cut off, which was only for oil systems, was not invented until 1923.

Front 171

Name 3 types of feedwater regulators

Back 171

Float Type, Thermo-expansion (mechanical) Copes, Thermo-hydraulic Bailey.

Front 172

Explain how a Bailey Feedwater regulator works.

Back 172

A Bailey feedwater regulator is known as Thermo-hydraulic. It uses a bellows to create pressure which opens and closes the feed valve depending on the level in the boiler. It has a finned tube placed at an angle at the normal operating water level. The cooling fins cool the water portion of the bellows. As the water level drops it exposes the tube to more steam causing the bellows to expand and open the feed valve.

Front 173

Explain how a Copes Feedwater regulator works.

Back 173

A Copes feedwater regulator works by mechanical Thermo-expansion. A thermo-expansion tube (thermostat) is inside an angled pipe at the normal operating water level. It is heated by both steam and boiler water. The steam side is insulated, but the water portion is not. This allows more heat to escape from the water portion of the tube. As the water level drops more steam contacts the expansion tube causing it to expand and open a feed valve to the boiler.

Front 174

They are both thermostatic so how to keep from getting confused about Copes and Bailey?

Back 174

B as in Bailey and hydraulic Bellows comes before C as in mechanical Copes

Front 175

What is latent heat and internal latent heat?

Back 175

Latent heat is the amount of heat in Btu needed to cause a change of state from a solid to a liquid or a liquid to a gas without a change in temperature. It takes 970.3 Btu, the Latent heat of Evaporation, to transform 1lb of water at 212°F to steam at 212°F

To get really technical, Internal latent heat is heat that causes the steam to expand and is capable of work. External latent heat is heat that pushes back the atmosphere and is unavailable for work. I don't think that's the answer they are really looking for though.

Front 176

Name 7 things on a Mollier chart

Back 176

Temperature, Pressure, Enthalpy, Entropy, Saturated Steam Curve, Superheated Steam Curve, Percentage of Moisture in Wet Steam

A Mollier diagram has a small portion of datafrom steam tables graphed onto enthalpy-entropy (h-S chart) coordinates.

Front 177

What are the steam table headings?

Absolute Pressure, Temperature

vf, vfg, vg, hf, hfg, hg, sf, sfg, sg

“vf-vfg-vg, hf-hfg-hg, sf sfg-sg EI-EI-O”

What else can you find on a Mollier chart?

Back 177

Absolute Pressure, Temperature, Specific Volume of Saturated Liquid (vf), Specific Volume of Latent Heat of Evaporation (vfg), Specific Volume of Saturated Vapor (vg), Enthalpy of Saturated Liquid (hf), Enthalpy of Latent Heat of Evaporation (hfg), Enthalpy of Saturated Vapor (hg), Entropy of Saturated Liquid (sf), Entropy of Latent Heat of Evaporation (sfg), Entropy of Saturated Vapor (sg)

A Mollier chart lists the values for superheated and saturated steam.

Front 178

What Times are best for paperwork???

Back 178

Standard Times, Cape Cod Times, Wrentham Times, etc. They're all good newspapers! Ha-ha! Keep Studying!

Front 179

Hey! You made it all the way to the end!

Back 179

Well, Good Luck! Ragweed Farmer