PIPE Flashcards
Is the ratio of the mass of water-vapor in air and the mass of air if it is saturated is called:
Humidity ratio
Mass ratio
Vapor ratio
Relative humidity
Relative humidity
Is the most common dryer used which consist of rotating cylinder inside which the materials flow while getting in contact with hot gas.
Tower dryer
Centrifugal dryer
Trey dryer
Rotary dryer
Rotary dryer
The hands feel painfully cold when the skin temperature reaches
8 deg C
10 deg C
12 deg C
14 deg C
10 deg C
The refrigerant used in steam jet cooling is: Steam R-11 Ammonia Water
Water
The total heat of the air is a function of WB temperature DP temperature DB temperature WB depression
WB temperature
Boiling point of Freon-12 at atmospheric pressure is: 21 deg F 15 deg F 5 deg F 28 deg F
21 deg F
Which of the following is NOT a type of water cooled condenser in refrigeration? Double pipe Double shell Shell and coil Shell and tube
Double shell
Component of absorption refrigeration system in which the solution is cooled by cooling water. Rectifier Generator Evaporator Absorber
Absorber
Cascade refrigeration cycle is often used in industrial process where objects must be cooled to temperature below:
- 46 deg C
- 56 deg C
- 66 deg C
- 76 deg C
-46 deg C
Type of refrigerant control designed to maintain a pressure difference while the compressor is operating. Thermostatic expansion valve Using low side float flooded system Automatic expansion valve Capillary tube
Capillary tube
As a rule of thumb, for a specified amount of compressed air, the power consumption of the compressor decreases by \_\_\_\_\_\_\_\_\_\_\_\_\_\_ for each 3 deg C drop in the temperature inlet air to the compressor. 1 percent 1.5 percent 2 percent 2.5 percent
1 percent
Modern way of detecting air compressor leak is by using Soup and water Air leak detector Acoustic leak detector Ammonia leak detector
Acoustic leak detector
For foundation of stacks, the maximum pressure on the soil is equal to the pressure due to the weight and the \_\_\_\_\_\_\_\_\_\_\_. Soil movement Wind movement Ground movement Engine movement
Wind movement
Foundation bolts of specified size should be used and surrounded by a pipe sleeve with an inside diameter of at least 3 times the diameter of engine bolt 2 times the diameter of engine bolt 3 times the diameter of anchor bolt 2 times the diameter of anchor bolt
3 times the diameter of anchor bolt
For multi stage compression of an ideal Brayton cycle, the back ratio will Increase Decrease Remains the same None of these
Decrease
Type of turbine that has a specific speed below 5. Impulse turbine Propeller turbine Francis turbine Deriaz turbine
Impulse turbine
A high discharge type of turbine Impulse turbine Propeller turbine Francis turbine Deriaz turbine
Propeller turbine
Use to minimize the speed rise due to a sudden load rejection Needle valve Wicket gate shut-off Shut-off valve Jet deflector
Jet deflector
Is the speed of a turbine when the head on the turbine is one meter Specific speed Rated speed Utilized speed Unit speed
Unit speed
Is a fluid property which refers to the intermolecular attraction by which the separate particles of the fluid arc held together. Cohesion Adhesion Surface tension Hypertension
Cohesion
Which of the following is NOT the cause of black smoke in diesel engine? Fuel valve open too long High compression pressure Carbon in exhaust pipe Overload on engine
High compression pressure
Which of the following is not a method of starting a diesel engine? Manual: rope, crank and kick Electric (battery) Compressed air Using another generator
Using another generator
Which of the following is NOT the cause of black smoke in diesel engine? Fuel valve open too long High compression pressure Carbon in exhaust pipe Overload on engine
High compression pressure
Two-stroke engine performs \_\_\_\_\_\_\_\_ to complete one cycle. Suction and discharge stroke Compression and power stroke Power and exhaust stroke Suction and exhaust stroke
Compression and power stroke
A type of geothermal plant used when there is a presence of brine extracted from underground Dry geothermal plant Double-flash geothermal Single flash geothermal plant Binary geothermal plant
Binary geothermal plant
Is the most important safety device on the power boiler. Check valve Gate valve Safety valve Globe valve
Safety valve
During hydrostatic test, the safety valves should be Removed Open Closed Partially closed
Removed
Where de-aerating heaters are not employed, it is recommended that the temperature of the feed water be not less than \_\_\_\_\_\_ 197 deg C 102 deg C 104 deg C 106 deg C
197 deg C
Is a reaction during which chemical energy is released in the form of heat. Cosmic reaction Ethnic reaction Endothermic reaction Exothermic reaction
Exothermic reaction
By reheating the steam in an ideal Rankine cycle the heat rejected will. Increase Decrease Remains the same None of these
Increase
By increasing the boiler pressure in Rankine cycle the moisture content at boiler exit will. Increase Decrease Remains the same None of those
Increase
Presently the highest steam temperature allowed at the turbine inlet is about \_\_\_\_\_\_. 340 deg C 520 deg C 620 deg C 1020 deg C
620 deg C
Two most common gases employed in Stirling and Ericsson cycles are. Air and helium Oxygen and helium Hydrogen and helium Nitrogen and helium
Hydrogen and helium
In most common design of gas turbine, the pressure ratio ranges from 10 to 12 11 to 16 12 to 18 15 to 20
11 to 16
In brayton cycle, the heat is transformed during what process? Constant temperature Isentropic process Isobaric process Isochoric process
Isobaric process
The fuel injection process in diesel engine starts when the piston \_\_\_\_\_\_ Is at the TDC Leaving TDC Approaches TDC Halfway of the stroke
Approaches TDC
If the cut-off ratio of diesel cycle increases, the cycle efficiency will Decrease Increase Remains the same None of these
Decrease
The fuel used in a power plant that is used during peak periods. Gas Solid Liquid None of these
Liquid
Typical compression ratio of Otto cycle is 6 8 10 12
8
If joule Thomson coefficient is equal to zero, then the process will become Isentropic Isenthalpic Isobaric Isothermal
Isothermal
If the fluid passed through a nozzle its entropy will: Increase Decrease Remains the same None of these
Remains the same
Refrigerant consisting of mixtures of two or more different chemical compounds, often used individuals as refrigerant for other applications. Suspension Compound reaction Blends Mixing of refrigerant
Blends
Pairs of mating stop valves that allow sections of a system to be joined before opening these valves or separated after closing them Check valve Gate valve Safety valve Companion valve
Companion valve
An enclosed passage way that limits travel to a single path. Corridor Hallway Lobby Tunnel
Corridor
For immediate dangerous to life or health (IDHL), the maximum concentration from which unprotected persons are able to escape within \_\_\_\_\_ without escape-impairing symptoms or irreversible health. 15 min 1 min 20 min 30 min
30 min
The volume as determined from internal dimensions of the container with no allowance for the volume of internal parts. Internal allowance Internal gross volume Internal interference volume Internal fits volume
Internal gross volume
A waiting room or large hallway serving as a waiting room Terrace Rest room Compound room Lobby
Lobby
A continuous and unobstructed path of travel from any point in a building or structure to a public way Average of aggress Mean of aggress Hallway of aggress Pathway of aggress
Mean of aggress
Any device or portion of the equipment used to increase refrigerant pressure Pressure relief device Pressure-imposing element Pressure lift device Pressure limiting device
Pressure-imposing element
The quantity of refrigerant stored at some point is the refrigeration system for operational, service, or standby purposes/ Pressure vessel Pump down charge Liquid receiver Accumulator
Pump down charge
Secondary refrigerant is a liquid used for the transmission of heat, without a change of state, and having no flash point or a flash point above \_\_\_\_\_\_ as determined from ASTM 150 F 160 F 180 F 200 F
150 F
A service valve for dual pressure-relief devices that allows using one device while isolating the other from the system, maintaining one valve in operation at all times. Three-way valve Two-way valve One-way valve Four-way valve
Three-way valve
Tubing that is unenclosed and therefore exposed to crushing, abrasion, puncture, or similar damage after installation. Protected tubing Bare tubing Open tubing Unprotected tubing
Unprotected tubing
Refers to blends comprising multiple components of different volatile that, when used in refrigeration cycles, change volumetric composition and saturation temperature as they evaporate (boil) or condense at constant pressure. Zeolite Blending Composition Zeotropic
Zeotropic
Is a premises or that of a premise from which, because they are disabled, debilitated, or confined, occupants cannot readily leave without the assistance of others Institutional occupancy Public assembly occupancy Residential occupancy Commercial occupancy
Institutional occupancy
Is one in which a secondary coolant is in direct contact with the air or other substance to be cooled or heated. Double indirect open spray system Indirect open spray system Indirect closed system Indirect, verted closed system
Indirect open spray system
Refrigerant number R-744 is Butane Carbon monoxide Propane Carbon dioxide
Carbon dioxide
Refrigerant number R-1150 is Propylene Ethene Ethane Methyl formate
Ethene
Refrigerant R-40 is Chlorodifluoromethane Difluoromethane Ammonia Chloromethane
Chloromethane
When the air duct system serves several enclosed spaces, the permissible quantity of refrigerant in the system shall not exceed the amount determined by using the total volume of those spaces in which the airflow cannot be reduced to less than \_\_\_\_ of its maximum when the fan is operating One-quarter One half-quarter Three-quarter One-fourth-quarter
One-quarter
The space above a suspended ceiling shall not be included in calculating the permissible quantity of refrigerant in the system unless such space is continuous and is part of the air return system Partition Plenums Separator Plate divider
Plenums
Which of the following is not a possible location of service valve? Suction of compressor Discharge of compressor Outlet of liquid receiver Outlet of condenser
Outlet of condenser
A coil in series with evaporator that is use to prevent the liquid refrigerant entering the compressor Accumulator Liquid superheater Drier loop Liquid suction heat exchanger
Drier loop
A type of valve connected from discharge of compressor directly to suction that is normally closed and will open automatically only if there is high discharge pressure Check valve Solenoid valve King valve Relief valve
Solenoid valve
Use to increase the capacity of condenser Water regulating valve De superheating coils Liquid-suction heat exchanger Condenser heating coils
De superheating coils
Is use to subcooled the refrigerant from the condenser Liquid subcooler Condenser subcooler Desuperheating coils Liquid receiver
Which of the following is NOT a part of low pressure side in refrigeration system? Compressor Condenser Liquid line Suction line
Liquid line
Which of the following is NOT a part of high pressure side in refrigeration system? Compressor Condenser Liquid line Suction line
Suction line
Which of the following is NOT a part of condensing unit? Compressor Discharge line Condenser Liquid line
Liquid line
By subcooling the refrigerant in refrigeration system, the compressor power per unit mass will Increase Decrease Remains the same None of these
Remains the same
Superheating the refrigerant in refrigeration system without useful cooling, the refrigeration effect per unit mass will Increase Decrease Remains the same None of these
Remains the same
By subcooling the refrigerant in refrigeration system, the specific volume at compressor suction will Increase Decrease Remains the same None of these
Remains the same
Pressure loss due to friction at the condenser, the compressor power per unit mass will Increase Decrease Remains the same None of these
Remains the same
Which of the following is NOT a type of air-cooled condenser? Shell and tube Natural draft Forced draft Induced draft
Shell and tube
A type of refrigerant control typically used in household refrigeration Thermostatic expansion valve Automatic expansion valve Capillary tube High side float
Capillary tube
Type of condenser that operates like a cooling tower Air-cooled condenser Evaporative condenser Shell and tube condenser Water cooled condenser
Evaporative condenser
The major problem of heat pump is Refrigerant used Outside air Supply air Frosting
Frosting
Dominant refrigerant used in commercial refrigeration system R11 R22 R12 R502
R502
Cascade refrigerant system are connected in Series Parallel Series-parallel Parallel
Series
Is use to heat up the solution partially before entering the generator in absorption refrigeration system Rectifier Absorber Regenerator Pump
Regenerator
The COP of actual absorption refrigeration system is usually Less than 1 Less than 2 Less than 3 Less than 4
Less than 1
Sight glass is often located at Discharge line Liquid line Between condenser and liquid receiver Suction line
Liquid line
Use to detects a vibration in current caused by the ionization of decomposed refrigerant between two opposite charged platinum electrodes Electronic detector Halide torch Bubble method Pressurizing
Electronic detector
The ability of oil to mix with refrigerants Carbonization Purging Mixing Miscibility
Joints and all refrigerants-containing parts of a refrigerating system located in an air duct carrying conditioned air to and from an occupied space shall be constructed to withstand a temperature of \_\_\_\_ without leakage into the airstream. 550F 600F 650F 700F
700F
Refrigerant piping crossing an open space that affords passageway in any building shall be not loss than ______ above the floor unless the piping is located against the ceiling of such space and is permitted by the authority having jurisdiction
- 2 m
- 2 m
- 2 m
- 2 m
2.2 m
Methyl chloride shall not be in contact with Aluminum Zinc Magnesium All of these
All of these
Shall not be in contact with any halogenated refrigerants Aluminum Zinc Magnesium All of these
Magnesium
Are suitable for use in ammonia system Copper Aluminum and its alloy Plastic Cast iron
Aluminum and its alloy
In a pressure-relief device is used to protect a pressure vessel having an inside dimension of 6 in or less, the ultimate strength of the pressure vessel so protected shall be sufficient to withstand a pressure at least \_\_\_\_ the design pressure 2 times 3 times 4 times 5 times
3 times
Seats and discs shall be limited in distortion, by pressure or other cause, to set pressure change of not more than \_\_\_\_ in a span of five years. 1% 5% 10% 50%
5%
Liquid receivers, if used or parts of a system designed to receive the refrigerant change during pumpdown charge. The liquid shall not occupy more than \_\_\_\_ of the volume when temperature of the refrigerant is 90F 80% 85% 90% 95%
90%
The discharge line (B4) shall be vented to the atmosphere through a \_\_\_\_ fitted to its upper extremity. Nozzle Convergent-divergent nozzle Pipe Diffuser
Diffuser
Convert fossil fuels into the shaft work Nuclear power plant Gas turbine power plant Dendrothermal power plant Thermal power plant
Thermal power plant
Ultimate strength drops by 30% as steam temperature raises from \_\_\_\_ for unalloyed steel 300 to 400 c 400 to 500 c 600 to 700 c 700 to 800 c
400 to 500 c
Recent practice limits steam temperature to 438 c 538 c 648 c 738 c
438 c
In a closed feed water heater, the feed water pass through Inside the tube Outside the tube Inside the shell Outside the shell
Inside the tube
Is use if extracted steam upon condensation gets subcooled Trap Deaerator Filter Drain cooler
Drain cooler
Needs only single pump regardless of number of heaters Open heater Closed heater Mono heater Regenerative heater
Closed heater
Is also known as deaerator Open heater Closed heater Reheat heater Regenerative heater
Open heater
Dissolve gases like \_\_\_\_\_ makes water corrosive react with metal to form iron oxide O2 and N2 O2 and CO O2 and CO2 N2 and SO2
O2 and CO2