Duff-Norton SK-2389-T Manuel d'installation, d'utilisation et d'entretien - Page 5
Parcourez en ligne ou téléchargez le pdf Manuel d'installation, d'utilisation et d'entretien pour {nom_de_la_catégorie} Duff-Norton SK-2389-T. Duff-Norton SK-2389-T 12 pages. Translating machine screw actuators
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1-4 Important Precautions
In order to ensure that Duff-Norton actuators provide
good service over a period of years the following
precautions should be taken:
1. Select an actuator that has a load rating greater than
the maximum load that may be imposed
on it.
2. The structure on which the actuator is mounted
should have ample strength to carry the maximum
load, and should be rigid enough to prevent undue
deflection or distortion of the actuator supporting
members.
3. It is essential that the actuator be carefully aligned
during installation so that the lifting screws are
perfectly plumb and the connecting shafts are
exactly in line with the worm shafts. After the
actuators, shafting, gear boxes, etc., are coupled
together, it should be possible to turn the main drive
shaft by hand. If there are no signs of binding or
misalignment, that actuator system is then ready for
normal operation.
4. Actuators should have a greater raise than is needed
in the actual application. Should it be necessary to
operate the actuator at the extreme limits of travel, it
should be done cautiously.
CAUTION
Do not allow actuator travel to go beyond specified
(catalog) closed height, or serious damage to internal
mechanism may result. Refer to table of specifications
(par. 1-3) for closed heights of respective units.
5. The worm shaft speed for these actuators should
not exceed 500 RPM for heavy loads, 1200 RPM for
light loads of one-fourth (or less) of the actuators load
rating.
6. The lifting screw should not be permitted to
accumulate dust and grit on the threads. If possible,
lifting screws should be returned to closed position
when not in use.
CAUTION
Where lifting screws are not protected from airborne
dirt, dust, etc., bellows boots should be used. Inspect
frequently at regular internals to be certain that a
lubricating film is present. Lifting screws should never
be run dry.
7. When using an 1800 (2000) or 9000 (10000) Series
Actuator, a periodic check of backlash of the lifting
screw thread is recommended to check wear of the
worm gear internal threads. The normal backlash on
a new unit of this type is approximately .010 inch.
Backlash of 50% or more of the thread thickness
indicates the need to replace the worm gear.
The 4800 and 9400 Series Anti-backlash Actuators
are designed to be adjusted for minimum backlash,
approximately .002 inch. The worm gear and anti-
backlash nut are manufactured to have a clearance
between their surfaces of 1/2 the thread thickness.
When adjustments have been made to the point
where all this clearance is gone, 50% of the thread
thickness is gone and replacement is necessary.
(See paragraph 2-8 for a detailed explanation of how
the anti-backlash nut functions.)
NOTE
For loads of from 25% to 100% of actuator capacity,
torque requirements are approximately proportioned to
the load.
8. The lubrication procedures for normal and severe
service conditions, as described in Section II,
paragraph 2-1, should be closely followed.
1-5. Warranty and Warranty Repair
Subject to the conditions stated herein, Duff-Norton
will repair or replace, without charge, any parts proven
to Duff-Norton's satisfaction to have been defective in
material or workmanship. Claims must be made within
one year after date of shipment. Duff-Norton will not
repair or replace any parts that become inoperative
because of improper maintenance, eccentric loading,
overloading, chemical or abrasive action, excessive wear,
or other abuse.
Equipment and accessories not of Duff-Norton's
manufacture are warranted only to the extent that they
are warranted by the manufacturer, and only if the
claimed defect arose during normal use, applications
and service. Equipment which has been altered or
modified by anyone without Duff-Norton's authorization
is not warranted by Duff-Norton. EXCEPT AS STATED
HEREIN, DUFF-NORTON MAKES NO OTHER
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE.
If you have any questions concerning warranty repair,
please contact Duff-Norton. Authorization for return
must be received from Duff-Norton before returning any
equipment for inspection or warranty repair.
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