Exxon Mobil Basic Operating Training Practice Test

These questions are part of the practice quiz. Start practicing

• The atomic number equals the number of what?
• Which term identifies the temperature at which a liquid will emit enough vapor to form a flammable mixture with air and be ignitable?
• What action is taken to prevent vapor loss when a fixed roof tank’s temperature exceeds the limit?
• How does temperature affect viscosity?
• What is the primary function of air-preheaters in a boiler system?
• In the four-step compression cycle, which step occurs first?
• Which statement best distinguishes TVP and RVP?
• What is the specific gravity of water?
• What is the relationship between volume and temperature for a gas?
• In the described boiler, what is the radiant section?
• In a steam turbine system, what is the role of the throttle valve?
• Which description best matches a dry sump lubrication system?
• What effect does external reflux have on the top of the tower?
• What does pipe schedule indicate?
• What is the function of a positioner?
• Cavitation involves vapor bubbles collapsing and generating what effect in the discharge line?
• What is meant by shut-off head, or dead head, in pumping?
• What is the stated approach to roof drains in the protocol?
• Why would a rupture disk be installed upstream of a PRV?
• What does a DP cell measure to determine liquid level?
• Which action is not part of the flooding response described in the material?
• Atomic mass is defined as the number of what?
• The atomic number is defined as the number of what in the nucleus?
• The measure of the average kinetic energy of a substance is defined as which property?
• Which mechanism transfers heat through electromagnetic waves without needing a medium?
• If the temperature exceeds the limit on a fixed roof tank, what is the recommended action?
• Which device has the secondary function of removing air condensable gases from the steam system?
• What is the purpose of a PV vent and how does it operate?
• What is the purpose of bearings?
• What does Dynamic Matrix Control combine to determine control actions?
• What is buffer gas?
• What is wet sump lubrication?
• Which device prevents backward flow in a system?
• Which mechanism transfers heat mainly via fluid motion?
• What is the purpose of external reflux?
• An internal floating roof tank is defined as which configuration?
• In a balanced draft boiler system, which components supply and exhaust combustion air?
• What is the purpose of a Fractionating Tower?
• Which device uses stripping steam to remove and dissolve oxygen from boiler feed water before it enters the boiler?
• Purpose of block valves?
• Why is a globe valve good for throttling?
• What is the typical target range for excess oxygen in combustion?
• Relationship between molecule size & boiling point
• In a process control loop, which element transmits the sensor signal to the controller?
• What describes potential energy?
• What is the purpose of the attemperator?
• What is the standard atmospheric pressure in inches of mercury as given?
• What is a catalyst?
• How do low-NOX burners reduce NOX production?
• What is the purpose of a cross head?
• Which of the following conditions is a common heater trip?
• What are the two main things of personal safety?
• Which items are listed as parts of an atom?
• What is the purpose of a governor?
• Atomic mass equals the sum of which particles?
• What is the purpose of thrust bearings?
• Which statement accurately describes the first and second electron shells according to the material?
• Cavitation occurs in a pump due to what phenomenon?
• What is the purpose of an impeller?
• How does a thermocouple work?
• What is counterflow in a heat exchanger?
• Which phrase best describes the flow of energy in a fluid system?
• What is required for heat transfer to occur?
• A benzene ring consists of how many carbon atoms with what bonding pattern?
• What is the purpose of tank Dykes?
• How does a bourdon tube function?
• What is a polymer?
• Relationship of gas volume, pressure, & temperature.
• How is coil outlet temperature controlled?
• Purpose of check valves?
• Why do we have to remove air/non-condensibles from a condenser?
• Which chemical is commonly used to treat water in the tower?
• What is a dry sump lubrication system?
• Before operating a valve, which information do you need to know?
• What happens to piping when it heats up?
• Which instrument is used to monitor and adjust draft pressure?
• The tank dyke design is intended to contain what in the event of a leak?
• What does condensation do in steam cycles?
• Why are burner block valves not throttled?
• Which statement correctly contrasts LEL and UEL?
• Which are the five elements of the process control loop listed?
• What is the purpose of pumparounds and how do they work?
• Which flow is typically considered better for heat transfer?
• How do side strippers work?
• At sea level, what is the standard atmospheric pressure expressed in psi?
• Which of the following sequences correctly represents the four steps of a compression cycle?
• What is parallel flow in a heat exchanger?
• Bottoms products in a distillation column are made of which type of hydrocarbons?
• When putting an exchanger in service, which side is always introduced first?
• In a boil over, where does the boiling water occur?
• What is the function of a controller?
• In a wet sump system, where is oil kept relative to rotating bearings?
• What are the three types of heat transfer?
• NOx is primarily formed under what condition?
• During a boil over, what happens to the boiling water at the bottom?
• The minimum flow line helps prevent which pump condition?
• What is the location and purpose of the balance drum on a centrifugal compressor?
• Which phrasing matches the roof drain handling described?
• Maintaining 2-5% excess oxygen primarily ensures what outcome?
• What method is used to prevent surge when dead head occurs?
• Which statement about the relationship between pressure and temperature for gases is true?
• What is the recommended response when flooding is detected?
• Why do some tubes have extended surfaces?
• In the event of a seal failure, what is the typical safety action?
• What is the primary function of a condenser in a steam power cycle?
• Which gas is used to pressurize accumulators in the seal oil system?
• What does COD stand for in the given material?
• What is NOx? Why do we care?
• What is the max vapor in fixed roof tanks?
• What is a boil over?
• Cascade control is defined as two controls working together, one an auto and one in Cascade.
• What are the products of an incomplete combustion reaction?
• Where is the labyrinth for separation gas located?
• If a process shows the production of carbon monoxide, what does it indicate about the combustion?
• Which option accurately describes roof drains according to the guidance?
• What is UEL?
• Which feature on a butterfly valve helps hold it in a fixed position and prevent movement?
• Thermal energy corresponds to which concept?
• How are roof drains managed?
• What is a benefit of steam turbines over electric motors?
• What is separation gas?
• What if specific gravity is <1?
• Which energy conversion occurs in the volute of a centrifugal pump?
• What is kinetic energy?
• Which device is used to start or stop flow in a pipeline?
• Which description best captures the reboiler's role in a distillation tower?
• What does DMC stand for in process control?
• Which condition can lead to cavitation in a pump?
• What is the purpose of a suction knockout drum?
• How is leakage between stages prevented?
• What is the basic process of distillation?
• How many electrons can occupy the second electron shell?
• Letdown steam flow is associated with which outcome?
• Overhead product is made of which type of hydrocarbons?
• How does the attemperator control the temperature of superheated steam?
• In a DP flow measurement, what role does the plate perform?
• What type of actuator converts pneumatic pressure into linear valve movement?
• Blue banding on insulation indicates what?
• Which of the following best defines a safety critical device?
• Which statement is listed as a common centrifugal compressor trip condition related to the seal oil system?
• How many BTUs are required to vaporize 1 pound of water at 212 degrees?
• Purpose of relief valves?
• What is auto refrigeration?
• Which lubrication system is used for the crankcase on a reciprocal compressor?
• Which pairing correctly matches the cooling device with its location in a multi-stage compressor?
• Endothermic reaction?
• What does TVP stand for in vapor pressure terminology?
• What are the concerns with fixed equipment vibration?
• What is the purpose of the blowdown system?
• The reason carbon forms four bonds is to achieve:
• How does a DP cell measure flow?
• What is the heat source to a tray?
• What is the boiling point?
• What hazards can result from an incorrectly installed dummy leg?
• What is velocity?
• What are alkenes?
• Which component does pumparound coolant?
• Single Point of Failure (SPOF) refers to a system condition where a single component's failure could cause what?
• What is the purpose of trays in a distillation column?
• Which component converts energy forms in the control system?
• Which valve is generally preferred for throttling because its disk wears evenly?
• Boil over occurs when which condition is met?
• What is the purpose of a seal flush?
• What is the purpose of a vacuum tower?
• Kinetic energy is best described as the energy of what?
• What is the cooling medium for a tray?
• How can you tell if a steam trap is working?
• Which valve automatically releases excess pressure to protect the system?
• Backwashing uses reverse flow to clean exchanger tubes by removing what?
• Which component provides the relief mechanism in a PV vent?
• If a tray gets hotter, what happens to the mixture on that tray?
• What is the purpose of a trip-N-throttle valve?
• Which statement best describes the primary cooling mechanism in a cooling tower?
• Which of the following best defines a catalyst?
• In a binary tower, from which location is the Overhead Product Withdrawn?
• In the natural draft system, which component regulates the rise of flue gas?
• True Vapor Pressure corresponds to which concept?
• What is the purpose of a binary tower?
• Which statement best describes a positive displacement pump's flow?
• Which group of valve types share a common 90-degree operational action?
• What is superheated steam?
• In a boiler with radiant, shock bank, and convection sections, which section lies immediately above the radiant section?
• Which statement best describes the relationship between fluid temperature and density?
• What is the convection section?
• Which statement accurately describes a boil over concept?
• What is the purpose of a roof drain?
• What is the purpose of purge mist in oil mist systems?
• Flooding occurs when there is not enough oxygen and what else happens?
• What is letdown v. total condensing?
• A BTU is defined as which of the following?
• What is the function of a deaerator?
• What is the purpose of the method of drying out steam?
• Which of the following reflects the roof drain procedure?
• Natural draft what is it?
• What creates flow through a Thermosyphon reboiler?
• Evaporation is the process by which a liquid turns into which phase?
• What are valence electrons?
• Why is there a biological risk with cooling towers?
• Which valves only require a 90 degree turn of the stem to go from fully opened to fully closed?
• What is autoignition?
• What does critical speed mean?
• What is the purpose of refractory in boiler construction?
• What is saturated steam?
• What is an accumulator used for in the seal oil system?
• What is purge Mist?
• What is the primary cooling mechanism in a cooling tower?
• Which mechanism transfers heat primarily through direct contact between solids?
• What is temperature?
• Which symptom is associated with flooding in a furnace?
• What is the temperature limit on a fixed roof tank?
• When a mixture of hydrocarbons is heated, which component boils first?
• What is the purpose of roof legs on a floating roof system?
• How does a dry gas seal differ from a traditional lubricated seal?
• NPSH is primarily used to evaluate the potential for cavitation in a pump. Which statement best aligns with this concept?
• How does a reciprocating compressor move gas?
• What is the static head pressure of a 20' column of water?
• What are the primary characteristics of a positive displacement pump?
• In a mechanical seal, which component helps maintain contact between the sealing faces?
• Vapor pressure is defined as which of the following?
• What happens if the throttle control is not used to regulate steam flow?
• What describes Thermosyphon reboiler operation?
• What is the function of a transducer?
• In cascade control, how are the two controllers arranged?
• Which term describes the energy required for a phase change without a temperature change?
• What is the purpose of baffles in a heat exchanger?
• The overhead product is composed of which type of hydrocarbons?
• What principle does a displacer level instrument use?
• How many gallons are in one cubic foot?
• What parameters can be measured with a DP cell?
• Which statement about boil over is true?
• What is the purpose of a pump warm-up line?
• What is horsepower?
• What is the risk of a failed check valve on the discharge of a centrifugal pump?
• Which statement about instrument air signal pressure is true?
• Which description matches an internal floating roof tank?
• What happens when a burner is shut down?
• Exothermic reaction?
• In valve safety practices, what should you verify before operating a valve?
• What is backwashing?
• What is flash point?
• What is the purpose of casing seals?
• What does LEL stand for in flammable vapor terms?
• How do you convert PSIG to PSIA?
• What are intercoolers?
• What is the numeric value given for atmospheric pressure in inches of mercury?
• Which device controls coil outlet temperature?
• What is the primary function of the impeller in a centrifugal pump?
• Which of the following best defines boil over in this context?
• What is the hydrostatic pressure of water per foot as stated?
• What is the purpose of a seal failure in a compressor system?
• What is viscosity?
• What is the shock bank?
• In valve safety rules, what should you know before acting and where should you stay out of line of fire?
• What is the purpose of unloaders and how do they work?
• What is an isomer?
• What types of chemicals are used in the tower?
• What is the purpose/operation of the clearance pocket?
• What mechanism does a constant level oiler rely on to supply oil as leakage occurs?
• What is the purpose of reclassifiers?
• What are the three things to remember of processed safety?
• Buffer gas usage: which area does buffer gas minimize process gas entering?
• In pump terminology, what is the volute designed to do?
• How should you correct a failed check valve in this setup?
• What are the four main process parameters to be monitored?
• Isomers are compounds with the same atoms but arranged differently.
• Which way do you turn a hand wheel to close a valve?
• How do you tell the position of a plug or ball valve?
• What is the pressure range for an instrument air signal? Why?
• Which statement best describes a safety critical device?
• What is the purpose of a pump min-flow line?
• What is the normal draft in a heater and why?
• What instruments are used to control draft in the system?
• If a tower pressure is increased, what happens to the products?
• Which of the following describes a reaction that releases heat to its surroundings?
• In the four-step compression cycle, which step comes after Expansion?
• Why is the exhaust valve open before steam supply?
• What describes thermal energy?
• Which hazard is associated with a sunken floating roof?
• Rules for PRV block valves require them to be in which state?
• A piping dead leg is defined as what?
• What is a primary use for positive displacement pumps?
• pH categories for acids and caustics?
• What are alkanes?
• How does an air ejector work?
• Which term describes the resistance of a liquid to flow?
• Which suction knockout drum condition is listed as a compressor trip cause?
• What are the aromatics?
• Which particles reside in the atomic nucleus?
• Valence electrons are found in which location?
• What are the products of a complete combustion reaction?
• What is the function of a constant level oiler?
• Which component is used to prevent axial motion in rotating machinery?
• What is the function of a reboiler?
• In a cooling tower system, what specific biological risk is identified?
• In a gas, how does viscosity change as temperature increases?
• Why do positive displacement pumps have a relief valve on the discharge?
• Purpose of throttle valves?
• What is the purpose of an independent high-level alarm?
• What is the purpose of packing/fill?
• A differential pressure (DP) cell is used to measure which parameters?
• What best describes a dry gas seal?
• How is pressure defined?
• What is a dummy leg? Hazards?
• Cavitation can cause the discharge to become what?
• Which statement best differentiates saturated steam from superheated steam?
• What are aftercoolers?
• A bourdon tube is best described as which of the following?
• What does NPSH stand for?
• Which factor can cause a sunken floating roof?
• What problem does the seal oil tank help overcome?
• What is the purpose of a seal oil tank?
• What are the three types of casing seals?
• How do you convert percent concentration to parts per million (PPM)?
• What is the boiling point of water at sea level in degrees Fahrenheit?
• What does PMI mean?
• What is the purpose of a reboiler?
• Cold Wall equipment refers to equipment that is protected by what?
• Which term describes the energy involved in changing a substance from liquid to vapor without a temperature change?
• In a heat exchanger startup, which side is introduced first?
• How many electrons can occupy the first electron shell?
• When a steam trap fails, is it better to fail open or fail closed?
• When can you NOT use a valve wrench?
• Why don't we throttle with gate valves?
• In a fuel-air mixture, what does 'Too rich' indicate?
• How does a pneumatic diaphragm actuator work?
• Which statement best describes roof drain handling?
• What does PCA stand for?
• What is the secondary function of a steam trap?
• What is the purpose of roof seals?
• Which statement correctly describes the vacuum tower's purpose?
• What is the purpose of a steam quench in seal systems?
• Which feature on the roof is designed to minimize vapor loss by adjusting with the tank conditions?
• For roof drains, which action aligns with the given instruction?
• What is the immediate effect described in a boil over?
• What is the maximum vapor pressure allowed in a floating roof tank?
• What is the primary purpose of a centrifugal pump?
• What is the purpose of pilots?
• Why does a butterfly valve have a locking handle?
• Why are registers closed on shut down burners?
• What is the typical amperage range for electronic control signals?
• In the four-step compression cycle, which step occurs after Intake?
• In flooding, which statement best describes the immediate effect on the flame?
• What does SPOF stand for?
• Which situation can lead to cavitation in a pump?
• Which statement correctly describes alkanes and alkenes?
• What is the primary function of steam traps?
• How should the block valve on a pressure gauge be lined up?
• How does a mechanical seal function?
• Rapid Vapor Pressure describes which property of a liquid?
• Which statement reflects how a thermocouple responds to temperature changes?
• Which of the following are common symptoms of cavitation?
• In a binary tower, what are the two primary product streams called?
• Which valve is designed to regulate flow instead of shutting it off?
• What is the purpose of a diaphragm in a compressor?
• What is a saturated hydrocarbon?
• Why does carbon make 4 bonds?
• Which condition is listed as a potential heater trip cause?