4
The jack advance circuit contains no safety relief valve. During
lifting, pressure must be controlled and monitored by the user, using
the pump relief valve and system hydraulic pressure gauge.
WARNING: Never operate jack at pressures above
4250 psi [293 bar]. Exceeding this pressure may allow
cylinder plunger to overextend during jack operation.
Cylinder plunger may eject from housing with extreme force.
Serious personal injury, loss of load and/or damage to jack may
result.
IMPORTANT: A working pressure of at least 1650 psi [114 bar]
is required to activate the jack's pilot-operated check valve when
the control valve is moved to the retract position. Jack will not
retract or may retract erratically if working pressure is less.
4.5 Using the Handle Assembly to Position the Jack
T
he jack can be lifted and positioned using the two carrying handles
(Figure 2, item 2) located on each side of the cylinder housing.
Adjust the jack position so that the cylinder load cap is centered
under the jacking point of the load.
WARNING: Lift the jack using the carrying handles
only. Do not lift the jack using the cylinder housing.
WARNING: Be sure that the jack is positioned on a
solid and level support surface, with the lifting cylinder
perpendicular to the ground. Jacking at an angle can
allow the jack to slip out of position, resulting in loss of load. As
required, use a swivel load cap to properly engage angled lifting
points. Refer to Section 5.6 for additional information.
5.0 OPERATION
5.1 Control Valve
Hydraulic flow to the jack lifting cylinder must be controlled by
an external 4-way, 3-position valve (user-supplied). See Figure 4.
• Move lever to the
extend position to
raise the load.
• Move lever to the
retract position to
lower the load.
• Move lever to the
neutral/hold position
immediately after
raising or lowering is
completed.
Note: Control valve location and mounting arrangement will vary.
For example, the valve may be installed on a portable hydraulic
pump or might be included as part of a truck-mounted PTO
power unit. Either a rotary or in-line style valve can be used.
5.2 Jacking Safely
You must know the weight of what you intend to lift. The jack
must be rated for at least 20 percent additional capacity.
All persons operating the jack should obtain and be familiar with
the American National Standards Institute rules that apply to
hydraulic rams and jacks (ASME ANSI B30.1) or the equivalent
standards used in your country or region.
WARNING:
Never place any part of your body under the
load at any time while it is being lifted, lowered or
hydraulically supported by the jack.
WARNING: The jack is intended for lifting purposes
only and should not be used to hydraulically support
the load for any period of time after the lift has been
completed. Support the load with suitable load supports
immediately after it has been lifted to the desired height.
WARNING: Never leave the jack unattended during
operation, even for a brief period of time. Closely
monitor jack operation at all times and be prepared to
stop lifting or lowering immediately.
WARNING: Do not use the jack outdoors in windy
conditions. Changes in wind direction or velocity could
cause the load to become unstable or fail.
CAUTION: Never exceed the maximum load rating of
the jack. Refer to Table 1 for load rating information.
5.3 Use of U-Rings Forbidden
The load holding U-Rings used on
various other Enerpac rail products
are NOT COMPATIBLE with the
model WJ60 wheel truck jack. See
Figure 5.
U-Rings should NEVER be used
with the jack. It is not designed to
function as a load holding device.
After lifting, all loads must be
immediately supported with support
stands (or other suitable load
supports) of appropriate load rating.
WARNING: Use of U-Rings with the model WJ60 wheel
truck jack will result in a potentially unstable lifting
arrangement. The load cap may become disengaged
from the cylinder plunger, allowing U-Rings to shift and load to
drop. Serious personal injury and/or property damage may result.
5.4 Operating Instructions
TO RAISE THE LOAD:
1. Be certain that the jack is positioned on a solid and level
surface, capable of supporting the load and the base of the
jack. Be sure that the lifting cylinder is perpendicular to the
ground.
2. If a high jacking point requires a taller jack, install extensions
and spacers (optional accessories) on the cylinder as
required. Refer to Section 5.5 for installation instructions
and additional information about extensions and spacers.
3. Place a piece of good quality plywood or other compression
material (approximately 1/4 inch [6,3 mm] thick with good
friction characteristics) between the cylinder load cap
and the jacking point. This will provide a small amount of
cushioning and will also help prevent damage to the jacking
point.
4. To raise the load, move the control valve lever to the advance
position.
CAUTION: When lifting with more than one jack, be
especially careful to keep the load level. Leveling is best
accomplished by alternately starting and stopping the
jacks to keep the load level enough so it remains stable.
5. When load has reached the desired height, move the control
valve lever to the neutral/hold position.
6. Be sure that load supports of appropriate load rating are in
place under the load.
4
Figure 5, Never use
U-Rings with jack!
$
37
%
Figure 4, Control Valve
(User Supplied)
