A pressure relief valve installed around the inlet block valve of a floating roof tank is adjusted to open at what pressure?

The pressure relief valve is crucial in managing and ensuring the safety of the system surrounding a floating roof tank. When dealing with floating roof tanks, it's essential that the pressure relief valve is adjusted to open at a level that allows for pressure fluctuation but also provides adequate protection against over-pressurization.

Setting the valve to open at 10% above the system dead head pressure accounts for variations in pressure that may occur during operation. This margin ensures that the tank can safely manage fluctuations due to temperature changes, vapor expansion, and other processes without risking a dangerous pressure buildup that could lead to tank failure or leaks.

This practice follows established safety protocols in fluid systems to prevent damage and maintain operational integrity, making sure pressures do not exceed safe operating limits. The 10% buffer over the dead head pressure allows the system to operate safely while still providing enough capacity for normal pressure variations.