Rupture discs are designed as one-time-use pressure relief mechanisms to safeguard tanks, pipes, and other pressurized components from excessive pressure or vacuum. They find application both in standalone and multiple-device relief setups, including serving as backup pressure relief devices. The simplicity and reliability of rupture discs stem from their lack of moving parts, ensuring rapid response compared to other pressure relief options. These devices are particularly effective against sudden pressure surges and are lightweight, enabling the use of high-alloy and corrosion-resistant materials which might be impractical for Pressure Relief Valves (PRVs).

Rupture discs also exhibit sensitivity to temperature changes. The burst pressure of these devices can significantly fluctuate based on their temperature, which might differ from the operating temperature of the fluid. As temperature increases, the burst pressure typically decreases. Rupture discs are versatile, designed for both gas (vapor) and liquid pressure relief scenarios, including those involving high viscosity fluids. When deploying rupture discs for liquid applications, careful consideration is required to ensure the disc design is apt for such service. They are quick to respond to pressure changes, making them applicable for a wide range of pressure relief tasks. These devices are crucial for preventing excessive pressure or vacuum hazards in various processes, safeguarding personnel, the environment, equipment, and the facility. Rupture discs are often used upstream of PRVs to create a sealed system for emission standards compliance, provide corrosion protection to the valve, and minimize valve maintenance requirements.

Perfect Engineering Services emphasizes the importance of rupture pressure in the safety mechanism. When a rupture disc is installed before a PRV, it’s essential that both devices are closely connected, sharing the same nominal burst and set pressure values. This close coupling is crucial in liquid service to minimize shock impact on the valve. According to the ASME Code’s UG-127, the space between the rupture disc and PRV must have a free vent, pressure gauge, try-cock, or an appropriate indicator to avoid undetected back-pressure buildup, potentially preventing the disc from bursting within its specified tolerance due to corrosion-induced leakage or other issues. Installing a rupture disc on the PRV’s outlet can also protect the valve from being exposed to atmospheric or downstream fluids, ensuring that the valve opens at the correct pressure regardless of any accumulating backpressure.