3-45.
Refer to figure 6-28 in your
textbook.
Which statement
relative to the operation of this
valve is false?
1.
The upper poppet is
controlled by the inside cam
2.
Fluid flow to the return line
is controlled by the lower
poppet
3.
Fluid flow from the pressure
line is controlled by the
upper poppet
4.
The lower poppet is unseated
by the outside cam to allow
the fluid to flow into the
cylinder and actuate the
piston
3-46.
When the pilot chamber of the
three-way, poppet-type, normally
closed directional control valve
is pressurized, fluid flows from
the actuating cylinder through
the valve and out the exhaust
port .
1.
True
2.
False
3-47.
Which four-way valves are
actuated by cams?
1.
Rotary spool
2.
Poppet
3.
Sliding spool
4.
All of the above
3-48.
Which type of valve is considered
most trouble free of all four-way
valves?
1.
Poppet
2.
Rotary spool
3.
Sliding spool
4.
Cam operated
3-49.
Which of the following represents
the flow of fluid as illustrated
in figure 6-34, view B in your
textbook?
1.
2.
3.
4.
Learning Objective:
Recognize
required characteristics,
functions,
types, and materials
of sealing devices used in fluid
power systems.
3-50.
Suitable packing devices for
fluid power systems are made from
materials that possess which of
the following characteristics?
1.
Compatibility with fluids
used in the systems
2.
Effective sealing ability
3.
Durability
4.
All of the above
3-51.
The term sealing devices is a
classification applicable to
packing materials used to provide
an effective seal between which
of the following parts?
1.
Two moving parts
2.
Two stationary parts
3.
A moving part and a
stationary part
4.
All of the above parts
combinations
3-52.
No internal leakage should be
allowed to occur within a
hydraulic power system because of
the resulting loss in system
efficiency.
1.
True
2.
False
3-53.
Which of the following factors
is/are used in determining the
material used as a sealing device
for a particular application?
1.
Location of the seal
2.
Storage of the seal
3.
Both 1 and 2 above
4.
Type of motion
3-54. Cork is suitable for use as
gaskets because of which of the
following characteristics?
1.
Its resiliency
2.
Its flexibility
3.
Its compressibility
4.
All of the above
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