Ilman Hasanov
This article investigates the influence of operating conditions on the service life of sealing assemblies used in oil, gas, and mining equipment. It is shown that the service life of sealing elements depends on their physicochemical properties and the structural characteristics of the sealing assemblies. Maintaining constant deformation is identified as a typical operating condition for various sealing systems. Under these conditions, stress relaxation occurs as a result of the gradual release of internal stresses until an equilibrium stress state is reached.The derived analytical expressions enable the prediction of sealing performance duration, the service life of sealing elements, and the initial stress required to initiate the stress relaxation process. The results demonstrate that polymer-based seals retain high elasticity over a temperature range extending from the embrittlement temperature to the upper service temperature limit. Furthermore, it is established that the hardness increase coefficient of polymers after thermal aging is independent of the embrittlement temperature. According to the proposed analytical model, the overall hardness increase coefficient is equal to the product of the hardness increase coefficients associated with low-temperature exposure and thermal aging. This relationship enables the independent evaluation of hardness changes under different operating conditions caused by low- and high-temperature effects.