STT-shaft twist tester NK

Twist test with digital camera

Define and document functional relevant surface structures

The requirements on a sealing surface varies in relation to their application. Therefore it is not possible to specify universally valid and explicitly tolerable surface parameters for the sealing surface. Nevertheless the sealing property of a shaft is conditioned by the roughness and the waviness of the surface. This functionally relevant overlap of roughness and waviness is visualized within an illuminated surface region of 2mm x 2mm by the Shaft Twist Tester. The roughness causes a characteristic scattered light distribution, whereas the waviness generates a stripe pattern in the test picture.

The device STT R100 NK which is connected to a digital camera captures and stores the characteristic scattered light patterns. By the use of the standard bajonett mount Micro-Four-Thirds (MFT) it is possible to connect the STT to every standard digital camera with MFT adapter. Via the LCD-display of the camera, the inspection takes place in the live image mode. The recorded pictures can be transferred to a PC through a USB-connection. The provided software makes the inclusion of the pictures into an inspection sheet possible. Using application-specified sealing surface samples (leak proof, leaky, limiting case) reference pictures of scattered light can be stated and used as reference samples for the quality inspection.production conditions. Additional the device STT R100 NO provides the possibility to connect a tripod (1/4” 20 UNC).

Application background

Measurement method

The requirements on a sealing surface varies in relation to their application. Therefore it is not possible to specify universally valid and explicitly tolerable surface parameters for the sealing surface. Nevertheless the sealing property of a shaft is conditioned by the roughness and the waviness of the surface. This functionally relevant overlap of roughness and waviness is visualized within an illuminated surface region of 2mm x 2mm by the Shaft Twist Tester.

The roughness causes a characteristic scattered light distribution, whereas the waviness generates a stripe pattern in the test picture. The device STT R100 NK which is connected to a digital camera captures and stores the characteristic scattered light patterns. By the use of the standard bajonett mount Micro-Four-Thirds (MFT) it is possible to connect the STT to every standard digital camera with MFT adapter. Via the LCD-display of the camera, the inspection takes place in the live image mode.

The recorded pictures can be transferred to a PC through a USB-connection. The provided software makes the inclusion of the pictures into an inspection sheet possible. Using application-specified sealing surface samples (leak proof, leaky, limiting case) reference pictures of scattered light can be stated and used as reference samples for the quality inspection.production conditions. Additional the device STT R100 NO provides the possibility to connect a tripod (1/4” 20 UNC).

STT-shaft twist tester Product video

Optional Accessories

Battery charger for STT
Charger + 2x battery
Voltage (batteries): 3.6 volts (lithium-ion battery)
High-quality universal 2-channel charger
LED status display
This item fits the following models: STT NO, STT NK, STT NV

Specifications

Technical information

Optical twist tester with digital camera
Direct visual twist test using the LCD display of the digital camera
Software for creating test reports
Twist period measuring range: DP 20 - 200 μm
Twist depth: Dt> = 200 nm *
Axial back focus: 15 mm
Shaft diameter: 5 - 200 mm
Illumination source: laser diode module laser class 2

* Information for Rz = 2 μm & nbsp; (information depends on roughness and twist period, permissible roughness. Ra 0.1 - 0.5 μm)