The article examines the ensemble of causes of premature wear of sealing elements in the Wankel engine under high-load operating regimes from the standpoint of the coupled evolution of sealing performance, thermal state, and tribological contact conditions. The aim of the study is to formalize the causal cascade of pressure, heat release, deformation, lubrication, and wear, and to interpret premature failure as the assembly's exit from its functional window rather than as a simple acceleration of material loss. The relevance of the work stems from the growing interest in highly loaded rotary power plants, where seal durability remains a key limitation to reliability and efficiency. Based on a synthesis of contemporary computational and experimental data on leakage dynamics, coating contact fatigue, and lubrication regimes, an integrated degradation framework is proposed that links local overheating, vibrational mobility of seals, and the transformation of wear mechanisms from abrasive and adhesive to fatigue and corrosion–chemical. The scientific novelty lies in the systematic description of failure scenarios for apex, side, and corner seals under load as self-sustaining loops, as well as in the emphasis on diagnostic indicators and engineering strategies for breaking the cascade through control of the thermal regime, lubrication, detonation, and the selection of tribological pairs. The article is intended for designers and researchers of rotary engines, tribology specialists, engine manufacturers, and operating engineers dealing with highly loaded units.

Wankel engine, apex seals, premature wear, high loads, tribology

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