3
GENERAL SPECIFICATIONS
The worm gear driven Ball Screw Jack
incorporates an alloy steel worm, which
drives a high tensile bronze worm gear,
accurately machined to the high standards
of Nook Industries for maximum load car-
rying capacity and uniformity of motion
transmission. All shafts are mounted on
heavy duty, anti-friction bearings to in-
crease operating efficiency of the drive
mechanism. Thrust bearings are provided
to support the rated thrust load of each
unit. Housings are made of high-strength
material, well proportioned to handle the
rated thrust and torque loads of each size
unit.
Ball Screw Jacks with translating screws
are fitted with a retainer for one direction
of travel only. Its purpose is to avoid inad-
vertently running the lifting screw out of
the jack and losing the balls from the ball
nut. THIS RETAINER IS NOT DESIGNED
TO FUNCTION AS A TRAVEL STOP. Care
must be taken if this stop collar is removed
as the ball screw can run out of the unit
and the recirculating balls will be lost from
the nut. Stops or collars are NOT provided
for units with traveling nuts unless specifi-
cally requested.
CAUTION - In the absence of internal or
external stops, it is possible to run the lift-
ing screw out of the unit. Your jack is NOT
equipped with internal stops unless spe-
cifically requested in your order.
A lifting screw cover is threaded into the
bottom of the unit on the upright model,
or in the top of the unit on the inverted
model, in order to keep the lifting screw
threads free of foreign material.
The lifting screw is made of 4150 heat
treated steel. The threads of the lifting
screw for all models should be well lubri-
cated and kept free of grit, dirt or other
abrasive contaminants.
Fabric type protective boots, or spiral steel
protectors, can be provided as an acces-
sory to protect the exposed portion of
the lifting screw. In the absence of posi-
tive stops, overtravel may crush protective
boots.
CAUTION - Standard units should not be
operated at input speeds over 1,800 RPM
without consulting the factory. Ball Screw
Jacks are designed for a maximum of
three hours of intermittent operation per
day. For values higher than three hours per
day, for any continuous operation, or for
repeated operation over any segment of
total travel, consult factory.
LUBRICATION
Gear Box Enclosure
The jack gearboxes are partially filled with
a lubricant at the factory unless otherwise
specified. Before operating any unit, verify
lubricant presence. All jack housings are
furnished with a grease fitting(s) and/or
pipe plug(s).
Lubricant inspection is recommended at
regular intervals. Once every six months
is satisfactory under normal operating
conditions, unless experience indicates
that regreasing should occur at shorter or
longer intervals. Severe operating condi-
tions such as high duty cycles, high am-
bient temperatures, or contamination will
shorten the lubrication inspection interval.
Lubricate internal jack components utiliz-
ing the grease fitting(s)/Port(s). When ap-
plying grease to the gearbox housing, suf-
ficient grease pressure is required in order
to properly apply grease to the bearing(s)
and worm gear. When applied at the facto-
ry, lubricant is typically applied at 5,000psi.
When utilizing an off-the-shelf, general-
purpose grease gun or auto lubrication
system, care must be taken to ensure
proper amount of lubricant is dispensed.
Only a small amount of lubricant would be
required. The below table is the amount
of lubricant applied at the factory. When
