How Pressure Vaccume breaker works used in oil tanker ship?

A Pressure Vacuum Breaker (PVB) on an oil tanker ship is designed to maintain proper pressure and prevent vacuum conditions in cargo tanks during loading, unloading, and transit. It operates by allowing air to enter the tank when a vacuum is created, thus preventing structural damage, while also venting excess pressure to avoid over-pressurization. The PVB features a spring-loaded mechanism that opens at specific pressure thresholds, ensuring safe and efficient cargo handling. This system is vital for maintaining the integrity of the tank and preventing spills or leaks.