Tribological behavior of lubricating tribo-systems for the watch industry

WHY

One of the main issues in the watch industry is reduce the friction and sticking between moving components. To achieve this, a small quantity of lubricant is added in the contact. However, due to the high expectations of the costumers, the increased lifetime of the watch, the size and geometry of components and contact conditions (loads in the mN range), there is a huge need to develop a tool that can evaluate such lubricating tribo-systems. The main challenge is to perform precision frictional measurements, in conditions that simulate the “actual” application.

HOW

The updated Basalt-N2 tribometer can perform precision frictional measurements in the load range of 0.2 mN up to 1N, which is relevant for such applications. Different contact geometries (point, line, area contacts) and sliding velocities can also be used to simulate different contacting components within the watch. Due to the high sensitivity of this tester the tribological phenomena such as sticking can be picked up. There is also a dwell (stop) time option, to simulate periodical movements e.g. hour and/or date change mechanisms, whereas the actual components can also be fixed onto specially design holders (customizing according to end-user).            

  

RESULT

•  The friction of lubricating tribological contacts in the mN range can be measured with precision.
• Repeatable measurements were obtained with the Basalt-N2.
• The testing parameters can be fined tuned to simulate the actual component conditions.
• The effect of loading, sliding speed and dwell time on the friction of tribological contacts for the watch industry can be measured.
• Comparison between different lubricants, materials and coatings is possible due to the precision of the sensors.