The long-term accuracy of a watch movement crucially depends on the lubrication of its moving parts – this is particularly true at extreme temperatures. We use the special oil developed by SINN to ensure reliable function under even the most extreme conditions. With its outstanding properties, it provides lubrication that is highly resistant to aging at temperatures between –45°C and +80°C.
The higher the temperature, the lower the viscosity of the lubricating oil film. At low temperatures, the oil becomes more viscous, leading to increased friction throughout the movement; more energy is lost in the train wheel, the escapement and the complete balance. Consequently, the amplitude of the oscillation decreases and the watch becomes increasingly inaccurate.
In conjunction with the aging of the oil, which likewise increases the viscosity of the oil, conventional watch oils can thicken enough that the watch stops at temperatures just below the freezing point. Such watches no longer function reliably when used at lower temperatures! Only the special oil with substantially lower viscosity developed by SINN for use in extreme temperatures provides reliable long-term lubrication at very low temperatures. The composition of the oil ensures that it is still sufficiently fluid at temperatures of –45°C and below to maintain the movement's proper mechanical function. Moreover, the viscosity of the oil at +80°C does not change enough to cause the oil to run off the ruby pallets of the escapement. Our SINN-Special Oil is highly resistant to aging, and provides lubrication for use under extreme conditions.
Lubrication using SINN oil is essential for a SINN watch capable of withstanding extreme temperatures from –45°C to +80°C. But oil alone isn’t enough. Just as important are the expansion and contraction rates of the movement’s individual components.
Here’s why: The watch’s movement contains various parts, made of different materials that respond differently to heat. That means when the entire movement is exposed to higher temperatures, the size of the components changes slightly. Some parts expand faster, and others more slowly. In some cases this can negatively influence the movement’s function, as the individual components no longer fit together precisely.
We respond to this negative effect by testing each individual watch in a climate chamber. Each and every watch must meet our strict quality standards even at extreme temperatures.