What is buffer gas?

• A. Labyrinths on the inboard side of the seal minimize process gas into seal area. You may inject buffer gas between the end board labyrinth.
• B. It is used to cool the seals
• C. It is used to lubricate the seal
• D. It is used to pressurize the bearing housing

Answer: (A)

Buffer gas is a protective gas injected into the seal region to create a barrier that reduces the intrusion of the process gas into the seal area. By introducing a clean, often inert gas between components like labyrinth seals, it helps sweep away any leaking molecules and keeps the seal faces in a cleaner, safer environment. This makes the seal less vulnerable to contamination or damage from process gas. It’s not primarily used for cooling, lubrication, or pressurizing the bearing housing, which is why those descriptions don’t fit the role of buffer gas.