A Fractal Model of Mechanical Seal Surfaces Based on Accelerating Experiment

ABSTRACT

The change in surface topography caused by friction and wear influences the wear properties and service life of mechanical seal. To investigate the wear properties of mechanical seals and obtain the variation in surface topography, it is practical to carry out accelerating experiments by increasing the load, speed, or temperature of the medium than safe life tests in the field device. Based on the assumption that the same fractal roughness corresponds to the same wear properties, the pi theorem was introduced to derive the relationship of wear under experimental and actual conditions. By providing detailed values of constants in the pi theorem through accelerating experiments, a fractal model was established to predict the life expectancy of mechanical seals. Under the state of mixed friction, measured values of surface topography for experimental stationary rings and data on a mechanical seal ring's service life in the field device were in accordance with those of the model. The establishment of the fractal model provides conditions for the performance study of long-period operating mechanical seals.

KEYWORDS:

• Mechanical seal
• fractal model
• fractal roughness
• pi theorem
• accelerating experiment

Funding

The research is financially supported by the National Natural Science Foundation of China (51375245) and Natural Science Foundation of Jiangsu Province (BK20130976).