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dryspin lead screw technology | General information dryspin lead screw technology | General information
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by means of axial spring pretension. In contrast to the PL
nut, a torsion spring is used with the ZB lead screw nut. In
conjunction with a friction disc and a fixing collar, it ensures
that ZB lead screw nuts are load-independent and therefore
also work with high axial loads and large thread pitches.
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Installation of lead screw nuts
dryspin lead screw nuts must be secured against twisting
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and axial migration. However, the lead screw nuts are not
10 pre-load lead screw nuts (PL) - designed for a press fit, since the oversize would have a
orange = pre-load direction negative effect on the thread clearance.
Pre-load lead screw nuts (PL) Lead screw nuts with flange
PL lead screw nuts reduce the axial clearance in a lead The maximum tightening torque for the flanged lead
screw drive by preloading two lead screw nut parts with a screw nut fastening screws is 2.5Nm. We recommend
compression spring. The spring pushes the two halves of the that assembly screws are secured with a semi-permanent
lead screw nuts apart axially in the direction of the spindle thread locking glue. Metallic ferrules should be used for
flanks. As long as the axial load in the lead screw drive is even higher tightening torques.
lower than the spring pretension, the entire lead screw drive
has a minimised backlash. This also permanently reduces Cylindrical lead screw nuts
clearance caused by wear. The outer diameter of cylindrical lead screw nuts is not
u Page 458 designed for a press fit. We therefore recommend the use
of spanner flats. In practice, a screw mount has proven to
be effective with low forces. Gluing lead screws nuts is not
recommended. If however, the securing of the lead screw
nuts by adhesives is planned, individual tests and iglidur
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material compatibility are necessary in each case.
Lead screw selection
The suitability and the operating behaviour of the system
largely depend on the lead screws used with the nut.
We recommend purchasing the nut and lead screw as a
system from one source. Lead screws are inspected with
Self-adjusting zero-backlash principle, DIN 103-compliant gauges. In principle, dryspin lead screw
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orange = pre-load direction drives can be used with lead screws made from steel,
stainless steel or hard-anodised aluminium. Split and LH/RH
Zero-backlash lead screw nuts (ZB) lead screws (right and left-handed threads on one lead screw)
One of the most precise solutions is the ZB lead screw are available in addition to right-hand and left-hand versions. coefficient of friction is lower compared to a dry-operating
nut. It consists of several components and is self-adjusting.
It is particularly suitable for lead screw drives with high Custom lead screws
helix threads for quick adjustment of small loads and Take advantage of our machining service - we manufacture
ensures minimal clearance over the entire service life. Ideal ready-to-fit lead screws based on your requirements. In
for precise positioning and feed movements in medical, addition to the standard sold by the metre option , we
laboratory and printing technology as well as in the wide also offer the possibility to machine the lead screw directly,
range of life sciences. The lead screw nut consists of a according to the specifications of the application, simply
support nut, a fixing collar with a torsion spring, a friction configured online with our free lead screw configurator. A
disc and the axial element. As with the PL nut, it works CAD software or knowledge in handling CAD programmes is
ASEAN 09/2023 ASEAN 09/2023
370 Online tools and more information u www.igus-asean.com/dryspin
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not required. Thanks to the integrated design tool, all entries
are automatically checked for plausibility. 2D dimensioned
drawing and 3D step file, generated directly online. The live
pricing also gives a good impression of the costs involved
in the individual processing steps. If a desired configuration
cannot be displayed via the online configurator, we would
be pleased to receive your enquiry. We will check the Wear [mg/km]
manufacturability and issue you with a quotation.
Custom nuts Diagram 01: Wear test on a rolled trapezoidal lead
Take advantage of our machining service even for custom screw
lead screw nuts - we manufacture ready-to-fit lead screw
nuts based on your requirements. Please send us your
drawing. We can then provide a quick quotation and 30
recommend the right material. 25
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Service life
dryspin lead screw nuts are made from tribologically 15
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optimised materials. Already during the development phase, 10
the focus is on optimising the friction properties of the Wear [mg/km] 5
dryspin lead screw drives, with the objective of attaining
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the lowest possible coefficient of wear and friction. In order 0 J W300 J350 A180 POM
to make the most precise statements about service life and Diagram 02: Wear test on a C15 lead screw
wear resistance, several hundred tests are conducted each Stroke 140mm, 50N, lead screw C15 rolled, 450rpm
year on the test equipment at the igus test laboratory in
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Cologne. Our experts will gladly test your application as
well. The results of these tests form the basis of our service 7
life calculation tools, such as our lead screw drive expert. 6
5
Lubrication 4
Many people think that greasing some products is essential
to ensure that they do not seize up and can continue a 3
smooth movement. However, it is easy to forget that Wear [mg/km] 2
lubrication is not a prerequisite for all products. 1
Our lead screw systems are developed for maintenance- 0
free dry operation. Basically, you should not compare J W300 J350 A180
a lubricated lead screw system one-to-one with a dry- Diagram 03: Wear test on a VA lead screw
operating system. Due to the external lubrication, the Stroke 140mm, 50N, lead screw VA rolled, 450rpm
lead screw system. However, the lubricant also causes a
high maintenance effort and additional costs that are often
not accounted for. In an abrasive environment, lubricants
can become an "emery paste" that damages the system. In
justified cases, however, external lubrication of iglidur lead
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screw nuts can be considered to reduce the coefficient of
friction or to increase the speeds without noise generation.
Please consult one of our experts to find out whether this
really makes sense for your application.
3D CAD files, prices and delivery time online u www.igus-asean.com/dryspin 371