Contamination
To prevent contamination, all hydraulic lines and fittings should be handled this way immediately after disconnecting them.
What is capped or plugged?
This is another term for a selector valve.
What is a directional control valve?
This is the most common cause of hydraulic system failure
What is contamination?
The two broad classes of gaskets.
What are metallic and nonmetallic?
The three principal categories of hydraulic fluids used in industrial applications.
What are minerals, polyalphaolefins, and phosphate esters?
This is the recommended service life for a pressure filter in the absence of specific manufacturer instructions.
What is 3,000 hours?
This type of valve is a variation of the poppet valve that can withstand high pressure and is almost leakproof in the closed position.
What is a check valve?
The three basic components of any hydraulic system.
What are the power supply, the actuator, and the control valves?
This type of dynamic seal is made of flexible material and is often used to seal around reciprocating or rotating shafts.
What are packings?
The three locations where filters are installed to control particulate contamination in a hydraulic system.
What are the pressure line, return line, and pump case drain line?
Phosphate ester based hydraulic fluid is susceptible to contamination from?
What is: water in the atmosphere.
This valve provides an outlet for excess fluid when a pre-set pressure is exceeded.
What is a relief valve?
The principle that states that a fluid confined in a container will transmit an equal pressure in all directions.
What is Pascal's Law?
This type of seal is used between two static surfaces to prevent leakage.
What is a gasket?
The primary purpose of a hydraulic system in a corporate setting.
What is to perform work by moving and lifting heavy loads?
If a system is serviced with the wrong type of fluid, this is the immediate action that should be taken.
What is to immediately drain and flush the system and maintain the seals?
This valve is designed to stop fluid flow in a line and is often a two-position, two-port poppet valve.
What is a shutoff valve?
This component stores fluid under pressure and releases it to supplement pump delivery.
What is an accumulator?
This term describes a failure mode where the seal material is worn away by a moving part
What is abrasion or wear?
The recommended practice for all hydraulic lines and fittings to prevent contamination immediately after disconnecting them.
What is capped or plugged?
Continuous passage of a liquid through a small orifice under pressure can produce high local temperatures that may do this to the fluid, even if the reservoir temperature is normal.
What is carbonize or sludge the liquid?
This valve is used to control the speed of an actuating cylinder.
What is a flow control valve?
In this type of system, fluid flows continuously through the system and back to the reservoir when the control valves are in the neutral position.
What is an open-center system?
The three main types of packings.
What are V-rings, U-rings, and cup packings?
This term is used to describe the process of cleaning and removing all old fluid from a hydraulic system before new fluid is added.
What is flushing?