Comparison of dimples and grooves based on friction and leakage properties of textured mechanical seals

PurposeThis study aims to obtain a design scheme of the surface texture on mechanical seal with lower friction and leakage by comparing two common texture types: dimples and grooves. Design/methodology/approachAn optimal free-form shape and an optimal circular shape were chosen by multi-objective optimization, and two types of grooves with different directions were chosen by a series of experiments. Then, the optimal free-form dimple, the optimal circular dimple, the groove perpendicular to the direction of movement (hereafter called groove-1) and the groove angled at 60 degrees to the direction of movement (hereafter called groove-2) were compared by experiments under different loads. FindingsThe optimal free-form dimple shows a better performance in terms of a lower coefficient of friction (COF) and a lower leakage than the other shapes, especially for the high speed and low load conditions. The reduction rate of COF is up to 37.5%, and the leakage rate is reduced by about 12.5%. The dimples have a lower leakage than the grooves. The groove angled at 60 degrees to the direction of movement is easier to pump the oil into the interface of the sealing face, leading to a lower friction but a higher leakage. Originality/valueThis study provides a feasible surface texture design scheme for improving the combination performance of mechanical seals.