Technical Interview Questions - 14 blog contains interview questions about Heat, principle of
heat transfer, hazardous area
classification drawing, natural gas, viscosity, pressure.
141. Why do we treat lowers API gravity crude to meet
product specification?
142. What is heat?
143. What is the basic principle of heat transfer?
144. What is the effect of boiling point in relation with
pressure?
145. What happens to vapor pressure when it rea
141. Why do we treat lowers API gravity crude to meet product specification?
Lower API crude requires high temperature and longer retention time to meet proper oil product specification.
142. What is heat?
It is an energy associated with the motion of molecules in a substance.
143. What is the basic principle of heat transfer?
Heat transfer is the transfer of heat from hot place to cold place.
144. What is the effect of boiling point in relation with pressure?
Boiling point increases at high pressure and decreases at low pressure.
145. What is the purpose of a hazardous area classification drawing? Give examples of Zone 0, Zone 1 and Zone 2
Hazardous areas are classified as
- Zone 0 (Class 0)
- Zone 1 (Class 1)
- Zone 2 (Class 2)
Examples of Zone 0, Zone 1 and Zone 2
Zone 0 = Always air fuel mixture is continuously present.
Example: Tank vents, Sump vents, Drains etc.
Zone 1 = Air fuel mixture is present during normal operations.
Example: Pipe line flanges, Inlet manifold areas. (Flange joints are the weaker areas in a process system that may cause leak during abnormal Operation).
Zone 2 = Air fuel mixture is may present during abnormal operations.
Example: Welded pipelines where there are no flange joints. This area reduces the chances of leaks. Flare lines, welded hydrocarbon pipelines where there are no flanges.
145. What happens to vapor pressure wh
