Cylinder Electronic Sensing . . . 141
Valving Designed for Cylinders . . . 143
Regeneration . . . . . . . . . . . . . . . . . . . . . . . . 143
Cylinder Drift . . . 144
Metering-In and Metering-Out Overrunning Loads . . . 147
Synchronizing Cylinders . . . 148
Cylinder Safety . . . 157
Do Not Attempt to Stall a Hydraulic Cylinder or Motor under Pressure . . . 152
Do Not Attempt to Mechanically Actuate
a Cylinder or Motor while It Is under Pressure . . . . . . . . . . 152
Chapter 7
Pressure-Control and Load-Holding Valves 157
Introduction to Pressure-Control and Load-Holding Valves . . . 157
Pressure-Relief Valves . . . 157
Direct-Acting Relief Valves . . . . . . . . . . . . . . . . . . . 158
Pilot-Operated Relief Valves . . . . . . . . . . . . . . . . . . 162
Adjusting Valves . . . 164
Pressure-Reducing Valves . . . 165
Unloading Valves . . . 167
Pressure-Sequence Valves . . . 168
Lift Check Valves . . . 170
Load-Holding Valves . . . 170
Pilot-Operated Check Valves . . . . . . . . . . . . . . . . . . 170
Counterbalance Valves . . . . . . . . . . . . . . . . . . . . 174
Chapter 8
Flow-Control Valves 179
Functions of Flow-Control Valves . . . 179
Regulating Speed . . . . . . . . . . . . . . . . . . . . . . 179
Regulating Priority . . . . . . . . . . . . . . . . . . . . . . 180
Dividing Flow . . . . . . . . . . . . . . . . . . . . . . . . 180
Non-Pressure-Compensated Flow-Control Valves . . . 180
Pressure-Compensated Flow-Control Valves . . . 182
Temperature-Compensated Valves . . . 188
Priority Valves . . . 188
Excavator Priorities . . . . . . . . . . . . . . . . . . . . . . 188
Proportional Flow Divider Valves . . . 189
Excessive Flow Protection . . . 191
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