Theoretical Prediction of Mixed Frictional Heat of Mechanical Seals Based on Shoulder-shoulder Contact Model of Asperities

doi:10.3901/JME.2017.21.102

Abstract

Abstract: Based on shoulder-shoulder contact model of asperities, mixed frictional heat expressions of mechanical seals are derived. The influences of rotational speed, friction gap and roughness on the frictional heat are also investigated. The results show common mechanical seals in mixed lubrication mostly operate with second elastic-plastic contact. The frictional heat from asperity contact takes more proportion of total frictional heat when ω ≤ 2 800 r/min is presented, but the viscous part gradually rises as the rotational speed increases and eventually equals to the total. Also, with the increased friction gap, the asperity and viscous frictional heat both decrease, however the former decreases to zero when d ≥ 2.8σ while the latter changes little. As the roughness of seal end faces increases, the total frictional heat dramatically falls first and then tends to invariable, which indicates it is profitable for reducing mixed frictional heat to properly increase the roughness on seal end faces.

Key words: friction gap, mechanical seal, mixed friction, roughness, shoulder-shoulder contact

CLC Number:

TB42

HU Qiong, SUN Jianjun, MA Chenbo, YU Bo. Theoretical Prediction of Mixed Frictional Heat of Mechanical Seals Based on Shoulder-shoulder Contact Model of Asperities[J]. Journal of Mechanical Engineering, 2017, 53(21): 102-108.

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