Lead screw technology FAQ

What does the dryspin® steep thread product range offer?

It offers a wide range of different lead screw nuts and lead screw models in various dimensions. The range of dryspin® high helix threads includes diameters from 4 to 20 mm and pitches from 2.4 to 100 mm. Due to the diversity of the product range, the dryspin thread geometry is conceivable in almost all applications.

Can drylin® lead screws replace conventional ball screws?

Basically, yes. It is necessary to adhere to the application parameters (axial load, rotation speed etc.) and reach the required positioning accuracy. Our lead screw drive expert offers optimal help for choosing the perfect lead screw system for every application.

What advantages does the dryspin® technology offer compared to conventional screw drives?

• Higher efficiencies
• Low-noise and low-vibration operation
• 30 % longer service life due to asymmetry
• Up to 25 % less wear
• Greater efficiency

How much can I save with my dryspin® lead screws?

Our drylin lead screw nuts are up to 50.9% more cost-effective than metal lead screw nuts. Also up to 69% more cost-effective compared to comparable plastic lead screw nuts and up to 50% more cost-effective compared to ball screw systems.

What does self-locking lead screw technology mean?

Self-locking means that lead screw nuts and lead screws cannot be moved without the application of external force. It has to do with the pitch and coefficient of friction.

In which temperature ranges can dryspin® screw drives be used?

Lead screw nuts that are made of tribologically optimised iglidur materials can be used in temperature ranges between -20°C and +150°C.

Which spindle bearing supports does igus® offer for dryspin® lead screw technology?

Our lead screw support blocks are available in thread sizes of 6-24 mm. Choice of mounting: plain bearings or, with higher dynamics, ball bearings (BB). All lead screw support blocks, like the matching lead screw clamp rings, are supplied in hard anodised aluminium.

How do I prevent unwanted bearing clearance?

In addition to the correct choice of material for the lead screw nut, a pretension mechanism against unwanted bearing clearance has proven to be an effective measure in practice. For trapezoidal threads and dryspin high helix threads, anti backlash, zero-backlash and low clearance versions with preload of the thread nut are available.

Can igus® screw drives be lubricated?

It is no secret that igus is an advocate of non-lubrication of bearings. Simply put, lubrication is not required for igus products. We often hear from customers the recurring question: “Can I use WD-40 or another lubricant to lubricate my bearing? ”

Offers igus® an alternative to the conventional DIN 103?

Our dryspin lead screw geometry is an excellent alternative to conventional trapezoidal threads. The wear tests show that the thread dimension with the dryspin geometry has up to 25% lower wear rate and up to 30% longer service life.

How can I reduce unwanted axial play in my lead screws?

To reduce the unwanted axial clearance, in addition to the correct choice of material, a preload mechanism has proven to be an effective measure. There are four variants with pretension for our dryspin high helix thread and trapezoidal threads: zero-backlash, low clearance, preload and AB lead screw nut.

What do I need to consider when fitting a cylindrical lead screw nut?
When installing a cylindrical lead screw nut made of plastic, axial and radial securing is necessary. An option for radial locking is the use of set screws. Axial fastening through a sheet metal ring possible.

What do I need to consider when installing a flanged threaded nut?
When fastening a plastic flanged threaded nut, it is particularly important not to exceed the maximum tightening torque of 2.5 Nm. It is also advisable to secure the fastening screws using a third medium, e.g. liquid threadlocker.

What can I do if the lead screw nut clears unintentionally?
To reduce the unwanted axial clearance, in addition to the correct choice of material, a preload mechanism has proven to be an effective measure. For our dryspin® high helix threads and trapezoidal threads there are three versions with preload: Zero-Backlash, Low-Clearance and AB lead screw nut. Here you will find all the advantages and assembly instructions for our clearance-reduced lead screw nuts.

How high are the loads that a sliding screw nut can withstand?
The special type of JGRM lead screw nut, in combination with a stainless steel plate, enables static loads of up to 6 MPa to be absorbed.

How are the dryspin® threaded spindles manufactured?
At igus, we distinguish between two manufacturing processes: thread rolling and thread whirling. Both processes have their special specifications. The company igus uses thread rolling as a standard process because of the cost savings, better surface finish and longer service life. Thread whirling is more suitable for small quantities and for very precise threads with narrow tolerances.

Can I customise my threaded spindle online?
From the idea to the finished spindle in just 5 minutes. The configurator enables engineers to quickly find the right lead screw and machine the ends from both sides. The application generates a dimensioned drawing of the configuration for you.

What is the difference between single and multi-start threads?
Single-start lead screws consist of only one thread. This means that the distance between the flanks, marked by pitch, is also the linear travel (lead) in millimetres per revolution of the lead screw.

If another thread is added, the lead screw reaches twice the stroke (2x pitch) with one revolution. The calculation for the linear travel always remains the same depending on the number of threads, only the pitch of a single thread differs. This procedure can also be applied to our multi-start dryspin® high helix lead screws.

What dimensions are available for replacing the DIN 103?
Our new dimensions are suitable for 1:1 exchange: DS10x3, DS14x4, DS18x4, DS10x2 and DS12x3. Here you can find more information about your exchange. If you have any questions, our experts will help you.

In which materials are the reduced-backlash lead screw nuts available?
The zero-backlash, low-clearance and preload lead screw nut are available in the high-performance polymer iglidur® J. The material can be used at almost all speeds and is characterised by a high degree of efficiency. The anti-backlash lead screw nut, on the other hand, can also be ordered in iglidur® J and additionally iglidur® R. The material iglidur® R enables a reduction of the vibrations between the threaded spindle and lead screw nut thanks to its damping specification and ensures low-vibration and low-noise running behaviour. 

In which materials are the dryspin® lead screw nuts available?
Our lead screw nuts are available in 6 different materials: iglidur® J, iglidur® 350, iglidur® R, iglidur® A180, iglidur® J200, iglidur® E7 and iglidur® W300.

How high is the manufacturing tolerance?
Apart from the pitch accuracy of 0.1mm to 300mm, customer-specific tolerances are implemented in the end machining of the lead screws and the machining of nuts.

How are the single start, multi-start and reverse trapezoidal thread spindles tolerated?
According to DIN 103, tolerance class 7e

Required effective support surface:
A_e = F_axial / p_admissible [mm²]

pv value:
pv = p_real x v

Surface Speed
v = n x d1 x π/ 60,000[m/s]

Rotational speed
n = v x 1,000 x 60 / π x d1 [1/min]

Feed rate:
s = n x P / 60,000 [m/s]

drive torque:
M_ta= F_axial x P / 2000 x π x η
M_te= F_axial x P x η/ 2000 x π