Copyright Goodheart-Willcox Co., Inc.
Chapter 18 Load-Sensing Pressure-Compensating (LSPC) Hydraulic Systems 453
Technical Terms
resolvers
secondary shuttle valve
signal network
signal pressure
stall mode
standby mode
torque-limiting control
upstream compensation
working mode
Review Questions
Answer the following questions using the information provided in this chapter.
1. Load-sensing pressure-compensating
hydraulic systems can be called all of the
following, EXCEPT:
A. Closed-center load-sensing system.
B. Negative flow control system.
C. Pressure compensation load-sensing
system.
D. Pressure and flow compensated system.
2. Which of the following terms can be defined
as a system that is designed to operate at a
fixed value above working pressure?
A. Load sensing.
B. Pressure compensating.
C. Stall mode.
D. None of the above.
3. Which of the following terms can be defined
as a system that provides a constant cylinder
speed for a fixed position of a DCV spool?
A. Load sensing.
B. Pressure compensating.
C. Stall mode.
D. None of the above.
4. What is the name of the valve that chooses
that higher working port pressure between
two different control valves and sends the
higher pressure to the pump compensator?
A. Shuttle valve.
B. Pressure-reducing valve.
C. Pressure relief valve.
D. Drop check valve.
5. What does John Deere’s agricultural division
call the valve that chooses the higher
working port pressure between two different
control valves and sends the higher pressure
to the pump compensator?
A. Nickel valve.
B. Dime valve.
C. Quarter valve.
D. Isolator.
6. What does Caterpillar call the valve that
chooses the higher working port pressure
between two different control valves and
sends the higher pressure to the pump
compensator?
A. Restitution valve.
B. Reiterator valve.
C. Resolver valve.
D. Isolator.
corner horsepower
differential pressure
dime valves
flow control spool
isolators
load-sensing (LS) hydraulic system
margin pressure
PQ curve
pressure cutoff spool
primary shuttle valve