| 摘要 |
The operation of a controlled leakage faceplate-type seal depends on pressure to develop a hydrodynamic film at its interface. The film prevents actual contact between the seal faces. When the pressure is low, the tendency to slam the seal faces together increases. In order to prevent rubbing the seal faces together, a lift-off system is provided to open the seal at a specified low pressure. When the pressure increases to a specified safe value, the system causes the seal faces to approach each other until the normal operating position is reached. |
