IDIS 403 CH 10 EXAM QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026
When heat cannot be properly dissipated, ___ must be placed in the system to help cool the hydraulic
fluid by removing damaging heat from the system. - Answers heat exchangers
A ___ filter is placed before components to protect them from contaminants in hydraulic fluid. -
Answers pressure line
Pressure Filter - Answers filter designed to operate in high pressures and is placed before one or
more hydraulic system components to protect them from contaminants in the hydraulic fluid
___ is a coating of a sludge-like residue that results form the breakdown of hydraulic fluid from the
heat and pressure. - Answers varnish
___ pressure is the level of pressure on the return line of a device in a hydraulic system. - Answers
back
A ___ is an artificial surface, usually a plate or wall, for deflecting, retarding, or regulating the flow of
fluid. - Answers baffle
Baffle - Answers helps clean and cool hydraulic fluid, separate out entrained air and water from
hydraulic fluid, and send hydraulic fluid to the pump
Air-cooled heat exchangers work best when the ambient temperature is lower than ____ degrees F. -
Answers 80
A ____ is used to allow air in and out of a reservoir as hydraulic fluid is pumped into the system. -
Answers breather/filler cap assembly
A ___ is a holding tank for hydraulic fluid that is not in use. - Answers reservoir
Water-cooled heat exchangers have a max operating pressure up to ___ psi. - Answers 200
Hydraulic fluid cleanliness is rated by standards developed by the ____. - Answers International
Standards Organization (ISO)
A ___ filtration unit is a nonfixed filtration machine that filters fluid as it is being transferred from a
storage vessel to the reservoir. - Answers portable
Strainer ratings can range from ___ micrometers to ____ micrometers. - Answers 22; 500
Absolute-rated filters with depth type elements are close to ___% efficient. - Answers 99
Contaminants in a hydraulic system are rated in ___ - Answers micrometers
Strainers typically have openings larger than ___. - Answers 50 micrometers
Electric heaters produce a low-heat output of about ___ W to warm the fluid but prevent it form
burning. - Answers 10
A ___ helps clean and cool fluid, separate out entrained air and water from the fluid, and send fluid to
the pump. - Answers reservoir
A ___ heat exchanger operates similar to an automobile radiator by dissipating heat through
convection. - Answers air-cooled
A ____ filter is designed to operate in a vacuum and is connected to the hydraulic system before the
pump and outside of the reservoir to protect the pump from contaminants in the reservoir. - Answers
suction line
A ___ is a device used to allow a visual inspection of the hydraulic fluid level in a reservoir at any given
time. - Answers sight gauge
A ___ is placed in a reservoir to attract and hold ferrous metal particles that have contaminated the
system but not been recovered by system filters or strainers. - Answers permanent chip magnet
A ___ is a device used to access a reservoir when it requires cleaning from the buildup of solid
material. - Answers clean-out cover
It is estimated that it costs ___ times more to extract contaminants form fluid than it does to prevent
them from entering a hydraulic system. - Answers 10
A ___ is commonly used to heat the hydraulic fluid in a reservoir. - Answers electric heater
A ___ is a foreign substance in the hydraulic fluid that is not meant to be part of the fluid. - Answers
contaminant
A ___ is a filter placed in front of the return line before it enters the reservoir. - Answers return-line
filter
Return Line Filter - Answers filter that is designed to operate in low pressures and is connected to a
main return line of the hydraulic system before the line enters the reservoir
A ___ rating is a value that indicates the diameter of the largest hard, sphere-shaped particle that can
pass through a filter under specific test conditions. - Answers absolute
When heat cannot be properly dissipated, ___ must be placed in the system to help cool the hydraulic
fluid by removing damaging heat from the system. - Answers heat exchangers
A ___ filter is placed before components to protect them from contaminants in hydraulic fluid. -
Answers pressure line
Pressure Filter - Answers filter designed to operate in high pressures and is placed before one or
more hydraulic system components to protect them from contaminants in the hydraulic fluid
___ is a coating of a sludge-like residue that results form the breakdown of hydraulic fluid from the
heat and pressure. - Answers varnish
___ pressure is the level of pressure on the return line of a device in a hydraulic system. - Answers
back
A ___ is an artificial surface, usually a plate or wall, for deflecting, retarding, or regulating the flow of
fluid. - Answers baffle
Baffle - Answers helps clean and cool hydraulic fluid, separate out entrained air and water from
hydraulic fluid, and send hydraulic fluid to the pump
Air-cooled heat exchangers work best when the ambient temperature is lower than ____ degrees F. -
Answers 80
A ____ is used to allow air in and out of a reservoir as hydraulic fluid is pumped into the system. -
Answers breather/filler cap assembly
A ___ is a holding tank for hydraulic fluid that is not in use. - Answers reservoir
Water-cooled heat exchangers have a max operating pressure up to ___ psi. - Answers 200
Hydraulic fluid cleanliness is rated by standards developed by the ____. - Answers International
Standards Organization (ISO)
A ___ filtration unit is a nonfixed filtration machine that filters fluid as it is being transferred from a
storage vessel to the reservoir. - Answers portable
Strainer ratings can range from ___ micrometers to ____ micrometers. - Answers 22; 500
Absolute-rated filters with depth type elements are close to ___% efficient. - Answers 99
Contaminants in a hydraulic system are rated in ___ - Answers micrometers
Strainers typically have openings larger than ___. - Answers 50 micrometers
Electric heaters produce a low-heat output of about ___ W to warm the fluid but prevent it form
burning. - Answers 10
A ___ helps clean and cool fluid, separate out entrained air and water from the fluid, and send fluid to
the pump. - Answers reservoir
A ___ heat exchanger operates similar to an automobile radiator by dissipating heat through
convection. - Answers air-cooled
A ____ filter is designed to operate in a vacuum and is connected to the hydraulic system before the
pump and outside of the reservoir to protect the pump from contaminants in the reservoir. - Answers
suction line
A ___ is a device used to allow a visual inspection of the hydraulic fluid level in a reservoir at any given
time. - Answers sight gauge
A ___ is placed in a reservoir to attract and hold ferrous metal particles that have contaminated the
system but not been recovered by system filters or strainers. - Answers permanent chip magnet
A ___ is a device used to access a reservoir when it requires cleaning from the buildup of solid
material. - Answers clean-out cover
It is estimated that it costs ___ times more to extract contaminants form fluid than it does to prevent
them from entering a hydraulic system. - Answers 10
A ___ is commonly used to heat the hydraulic fluid in a reservoir. - Answers electric heater
A ___ is a foreign substance in the hydraulic fluid that is not meant to be part of the fluid. - Answers
contaminant
A ___ is a filter placed in front of the return line before it enters the reservoir. - Answers return-line
filter
Return Line Filter - Answers filter that is designed to operate in low pressures and is connected to a
main return line of the hydraulic system before the line enters the reservoir
A ___ rating is a value that indicates the diameter of the largest hard, sphere-shaped particle that can
pass through a filter under specific test conditions. - Answers absolute
