Hebei Hankai 25 40 7 oil seal

The applications of high temperature oil seals span a wide range of industries. In the automotive sector, they are commonly used in engine components, transmission systems, and various driveline applications. High temperature seals are essential in maintaining the integrity of systems that operate under extreme thermal conditions, such as turbochargers, where exposure to high temperatures is prevalent. Additionally, in the aerospace industry, these seals are crucial for ensuring the reliability of engines and hydraulic systems, where failure can lead to catastrophic consequences.
The question of why manhole covers are typically round (in some countries) was made famous by Microsoft when they began asking it as a job-interview question.[8] Originally meant as a psychological assessment of how one approaches a question with more than one correct answer, the problem has produced a number of alternative explanations, from the tautological (Manhole covers are round because manholes are round)[8] to the philosophical.