At what pressure does the green rupture disk rupture?

• A. 2775 PSI
• B. 2500 PSI
• C. 3000 PSI
• D. 2000 PSI

Answer: (A)

Rupture disks are safety devices that stay intact until the system pressure reaches their predetermined burst pressure. The color on the disk identifies its exact rating, and for this installation the green disk is rated to rupture at 2775 psi. When the pressure climbs to that level, the disk ruptures and vents to prevent overpressure and protect the system from damage, while normal operation stays below this threshold. If a disk with a lower rating were used, venting would occur too early and could compromise system performance; if a higher rating were used, the disk might not relieve pressure in time to prevent damage. So, 2775 psi is the intended rupture pressure for the green disk.