ESF Thüringen - Liste der Vorhaben Förderperiode 2014-2020

shaft twist tester charger set

Shaft Twist Tester NK

Documented density of radial shaft sealings!


The demand on a sealing seat vary in dependence on the application. Due to that it is not possible to specify tolerateable and universally valid surface structure parameters for the sealing surfaces of the shaft. The density of a shaft is still determined substantially by the roughness and the waviness of the surface. This function relevant overlapping of roughness and waviness is illustrated in a surface cutting of approx. 2 mm x 2 mm with the help of the optical twist check.

The surface roughness causes a typical scattered light distribution, while surface waviness generates declension stripes in the test picture. With the help of the device STT R100 NK, which is provided with a digital camera, these typical scattered light pictures can be documented photographically. The testing set with the customary digital cameras, which dispose of a change objective adaptor MFT, can be equipped by the use of the standardized bayonet joint Micro-Four-Thirds (MFT).

Through the LCD display of the digital camera the optical twist check occurs in the live picture mode. The taken images can be transfered to a processing unit via USB connection and integrated into a test protocol with the help of provided software. On the basis of the application-specific sealing pattern parts (close, leaking, borderline case) reference-scattered light pictures can be expelled and be used as a comparative pattern for an optical good-bad twist check.

Technical features

Range of measurement:

Twist period length Dp = 20 - 200µm

Depth of twist Dt > 200nm*


Axial length of contact area: 15mm

Shaft diameter: 5 - 200mm  
Number of Pixels: 4096 x 3084  
Optical twist tester with digital camera  
Data transfer via USB  
Software to compile inspection sheets  
Visual twist testing on LCD display  
*Depending on the roughness and twist period. Admissible roughness Ra = 0,1 - 0,5 µm  


<< Back to overview

Order the STT charger set at the same time:


- Charger + 2x battery (similar to image)


- Voltage (battery): 3,6 volt  (branded lithium ion accumulator)

- premium universal 2-chanal-charging device (no self-drain, no memory-effect)

- LED status display

Suitable for: