Twist testing on screen!

Twist structures can differ distinctly over the whole seal seat circumference. The local dependency is characterized by varying portions of roughness and waviness. Consequential the periodicity of the twist structure is disturbed. However, the partitions of the seal seat surface with dominating twist structures cause leakage. In this case a 100%-inspection of the surface over the circumference is recommended.


STT-shaft twist tester NV

STT-shaft twist tester NV

STT-shaft twist tester NV & PC

STT-shaft twist tester NV & PC


Especially long wave twist structures (DP 200μm) are difficult to prove. The disturbed periodicity leads to a non-continuous stripe pattern. Above a period length of 200μm the spacing between the diffraction lines is very small and it is difficult to resolve it with human eye. The pictures recorded by the video camera are magnified by a factor of 4 and displayed on a screen. That leads to a clearly improved resolution of long wave twist structures (200μm - 500μm).

The STT R100 NV is principally designed for the stationary 100%-inspection of seal seat surfaces close to the manufacturing process and is connected to a video camera and a screen. The Video camera can also be readout by a PC via a standard TV tuner card. The disturbed diffraction lines pattern can be compacted to standing lines, while rotating the shaft between centers or in the lathe chuck, which indicates the presence of twist.


Technical Features:

  • Measuring range: twist period Dp = 20 - 500μm
  • Twist depth: Dt> 200nm *
  • Axial bearing dimension: 15mm
  • Pixel: 752x582
  • Optical twist tester with video camera Watec WAT-231S2 for live image transmission on a monitor
  • Pal Composite Video Signal Output (optional with USB port available)


Akku-Ladegerät für STT

Optional Accessories

  • Battery charger for STT
  • Charger + 2x battery
  • Voltage (batteries): 3.6 volts (lithium-ion battery)/li>
  • high-quality universal 2-channel charger (no self-discharge and no memory effect thanks to lithium-ion technology)
  • LED status display
  • This item fits the following models: STT NO, STT NK, STT NV





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