Wood’s Powr-Grip FL4HV11AC - Manual (Page 13)

Rev 15.0/1-14 11 FL4HV11AC: #35030
Positioning the Lifter on the Load
Make certain that the contact surfaces of the load and all vacuum pads are free of any
contaminates that could harm the pads or prevent them from sealing against the load (see
MAINTENANCE: V
ACUUM
P
AD
M
AINTENANCE
). 6
WARNING: To avoid accidental load release, always center lifter’s pad frame on
load.
Center the lifter’s pad frame to within 2" [5 cm] of the load center, since off-center loading could
result in a load release and possible injury to the operator, and it may also damage the lifter. 7
Make sure that all activated vacuum pads will fit entirely on the load’s contact surface (see
SPECIFICATIONS: Pad Spread) and that they will be loaded evenly while lifting (see
SPECIFICATIONS: Per-Pad Load Capacity). Then lower the lifter onto the load until all pads are
touching the contact surface.
Sealing the Pads against the Load
Move the lever on the vacuum control valve to the “APPLY” position: Pull upward on the lever's
knob, move the lever all the way forward (away from operator) and release it. This position
opens the lifter’s vacuum lines to the airflow created by the vacuum pump, causing vacuum to be
drawn immediately at the vacuum pads.
8 Apply the lifter to the load until all the pads seal
against it.
WARNING: Keep valve lever in “APPLY” position throughout lift.
The valve lever must remain in the “APPLY” position throughout the entire lift. Any interruption
of the vacuum flow during lifter operation could result in the release of the load and possible
injury to the operator.
Note: If a vacuum pad has been lying against a hard object (as during shipping), it may be
slightly distorted. Although initially it may be difficult to apply the pad to a load, this condition
should correct itself with continued use.
Reading the Vacuum Gauge
The vacuum gauge indicates the current vacuum level in the lifter’s vacuum system. The green
range indicates vacuum levels sufficient for lifting the maximum load weight, whereas the red
range indicates vacuum levels that are not sufficient for lifting the maximum load weight. The
gauge needle should show a sudden surge in vacuum as the vacuum pads seal against the load.
If it takes more than 5 seconds for the vacuum level to reach 5" Hg [-17 kPa], press on any
activated pad that has not yet sealed.
6
Since oil damages the rubber in standard pads, the load surface must be free of oil unless the lifter is equipped with optional
oil-resistant pads, which may be used on oily surfaces.
7
The lifter is designed to handle the maximum load weight (see SPECIFICATIONS: Maximum Load Capacity) when the load’s
center of gravity is positioned within 2" [5 cm] of the pad frame’s center point. Occasional loading deviations are permissible,
provided that the operator can maintain control of the load at all times and that the load weight is low enough to avoid damaging
the lifter.
8
To minimize the time it takes for the lifter to attach and obtain full vacuum, do not place the valve lever in the “APPLY” position
until the vacuum pads are contacting the load.