It is well known that static seals are usually designed to be used once.In this paper,we discuss the reusability of a type of static seal called the spring energized metal C ring,which is required to be reused 4–5 ti...It is well known that static seals are usually designed to be used once.In this paper,we discuss the reusability of a type of static seal called the spring energized metal C ring,which is required to be reused 4–5 times without maintenance during the lifetime of the pump.A theoretical analysis based on the nonlinear finite element method and an experimental investigation of the reusability of the C ring are carried out.The effects of the elastic modulus of the ring material,the ring wall thickness,the amount of assembly interference between the spring and the C ring,the operating temperature and the compression ratio are discussed.The parameter S,which denotes the reaction force difference percentage,is determined to measure the reusability of the C ring.The results show that the ring wall thickness plays an important role in the reusability.Although the normal force of a thick wall decreases after the ring is reused eight times,the value is still higher than the first normal force of a thin wall.In contrast,the elastic modulus of the material has the lowest impact.Here,a pre-compression ratio of 18.2%not only produces a larger first normal force but also leads to a smaller reduction in the normal force when the ring is reused.A simulated experiment is carried out to investigate the influence of the coating of the C ring on its reusability.The results show that when plastic deformation occurs on the contact surface,the contact state of the C ring coating becomes a major factor that affects the seal performance.Aging treatment at high temperatures(250°C)reduces the binding force of the silver coating on the spring energized metal C ring,which leads to the deterioration in the reusability of the ring.展开更多
基金supported by the National Key S&T Special Project(Grant No.2012ZX06901-022)
文摘It is well known that static seals are usually designed to be used once.In this paper,we discuss the reusability of a type of static seal called the spring energized metal C ring,which is required to be reused 4–5 times without maintenance during the lifetime of the pump.A theoretical analysis based on the nonlinear finite element method and an experimental investigation of the reusability of the C ring are carried out.The effects of the elastic modulus of the ring material,the ring wall thickness,the amount of assembly interference between the spring and the C ring,the operating temperature and the compression ratio are discussed.The parameter S,which denotes the reaction force difference percentage,is determined to measure the reusability of the C ring.The results show that the ring wall thickness plays an important role in the reusability.Although the normal force of a thick wall decreases after the ring is reused eight times,the value is still higher than the first normal force of a thin wall.In contrast,the elastic modulus of the material has the lowest impact.Here,a pre-compression ratio of 18.2%not only produces a larger first normal force but also leads to a smaller reduction in the normal force when the ring is reused.A simulated experiment is carried out to investigate the influence of the coating of the C ring on its reusability.The results show that when plastic deformation occurs on the contact surface,the contact state of the C ring coating becomes a major factor that affects the seal performance.Aging treatment at high temperatures(250°C)reduces the binding force of the silver coating on the spring energized metal C ring,which leads to the deterioration in the reusability of the ring.