Buffer gas usage: which area does buffer gas minimize process gas entering?

• A. Bearing housing
• B. Seal area
• C. Suction line
• D. Discharge line

Answer: (B)

Buffer gas creates a protective barrier at the seal interface, preventing process gas from entering the inside of the equipment. By filling the seal area with buffer gas (often inert) at a controlled pressure, any leakage from the process gas is flushed away with the buffer gas rather than migrating into the bearing housing or lubrication zones. This keeps the seal faces clean and protects bearings and lubricants from contamination. The suction and discharge lines are the gas flow paths, while the bearing housing is a secondary concern; the primary purpose of buffering is to shield the seal area itself from process gas ingress.