Flanged joints are formed by bolting two flanges together with what between them to provide a seal?

• A. A cement
• B. A gasket
• C. A tape seal
• D. A rubber O-ring

Answer: (B)

Sealing a flanged joint relies on a gasket placed between the mating flange faces. When the bolts are tightened, the gasket is compressed and fills microscopic gaps on the flange surfaces, creating a tight, leak-proof barrier that can withstand the internal pressure. The other options don’t provide a reliable, removable seal for this typical arrangement: cement isn’t used for sealing flanged joints because it doesn’t handle pressure or allow disassembly; a tape seal isn’t designed to endure the bolted compression and fluid pressure of a flange connection; and a rubber O-ring requires a groove and is used in different flange designs, not the standard flat-face joint. Gaskets are selected from materials compatible with the irrigation fluid and service conditions to maintain a durable seal.