Study on the Frictional Wear Characteristics of FKM Ring Seals under Real-Time Temperature and Abrasive Conditions
Abrasion loss of rubber seals seriously affects their service life,and the decay of seal mechanical properties due to formation temperature and material abrasion loss due to rock chip intrusion during downhole drilling are both impor-tant factors that aggravate the failure of rubber seals.In order to investigate the abrasive wear mechanism of fluororubber(FKM)seals under the combined effect of real time temperature environment and abrasive conditions,by simulating the actual working conditions of downhole,the abrasive wear experiments on FKM seals and SS304 steel pairs under real-time temperature were conducted.The reasons for the change in the mechanical properties of FKM seals under real-time temper-ature and the reasons for the transformation of the contact form of FKM/SS304 mating pairs were explored.The changes in wear mechanism of fluororubber seals,and their effects on friction coefficient,wear amount and the surface wear topography of mating pairs were analyzed.The results show that the mechanical properties of FKM,such as hardness and modulus of elasticity,deteriorate significantly when the real-time temperature rises to 60 ℃.The decline of the mechanical properties causes the contact form between the seals to change from three-body contact to two-body contact;the rubber surface wear profile changes from craters caused by three-body wear before 60 ℃ to surface material stripping during two-body wear,and the metal surface wear profile also changes from furrow-based to scratch damage;the rubber abrasive profile also gradually changes to strip abrasive due to the change of the wear mechanism.This thesis reveals the changes of contact forms and wear mechanisms of downhole drilling tool seals under real-time temperature and abrasive conditions,provides a basis for the selection and performance optimization of downhole drilling tool seal materials,and provides methodological references for related research,as well as theoretical support for the study of material damage mechanisms under the action of temperature and particles in service.