JLG GRADALL 522 Owner'S/Operator'S Manual Download

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TABLE OF CONTENTS

System Schematic...........................................................................................................................Page 2
Representative Performance Data......................................................................................................Page 2
Description and Operation of Power Brake Valve......................................................................Pages 3, 4 & 5
External Dimensional Views...............................................................................................................Page 5
Installation of Power Brake Valve........................................................................................................Page 5
Cross Sectional Views of Three Power Brake Valve Designs.................................................................Page 6
Specification Chart...........................................................................................................................Page 7
Primary Cup Design..................................................................................................................Pages 8 & 9
Teflon Seal Design.................................................................................................................Pages 10 & 11
Sliding Piston Design.............................................................................................................Pages 12 & 13
Service Diagnosis...........................................................................................................................Page 14
Bleeding...............................................................................................................................Pages 14 & 15

PERFORMANCE DATA (Typical)

Flow capacity.................................................................................See Specification Chart (page 7)
System pressure..........................................................................................................0 - 2000 psi
Brake line pressure.........................................................................See Specification Chart (page 7)
Master cylinder, capacity......................................................................................................3.1 in.

Push rod travel with power...........................................................................................0.2” (approx.)
Push rod force with power.................................................... .340 lbs. at 1500 psi brake line pressure
225 lbs. at 250 psi brake line pressure (Model 06-460-652 only)
Push rod travel without power...................................................................................1.844” (approx.)
Push rod force without power..............................................................................1500 lbs. at 725 psi

518 lbs. at 250 psi (Model 06-460-652 only)

NOTE: Brake system rubber parts (Buna-N) must be compatible with mineral based hydraulic oil.

SYSTEM SCHEMATIC (TYPICAL)

FIGURE 1

(2)

BRAKE

POWER

STEERING
CYLINDER

RESERVOIR

RETURN

LINE

FLOW-