Pressure Vessel Safety: Leak Before Burst

Pressure vessels are, by nature, volatile and potentially dangerous. The job of a pressure vessel is to hold a liquid or gas at a certain temperature that is different from the outside temperature. Pressure vessels are used in a variety of industrial processes to distill liquids, compress air, hold hydraulic and pneumatic fluids and much more. Due to the highly dangerous nature of these products, there are many different regulations placed onto any pressure vessel manufacturer to ensure the safety of the vessel and the employees using the vessel.
The regulations for each pressure vessel manufacturer vary depending on where the vessel is in use. Most countries have their own unique regulation system, but some regulations cross countries. Some of the most common guidelines regulating the design of pressure vessels come from the ASME Boiler and Pressure Vessel Code in North America, the Japanese Industrial Standard, the CSA in Canada, and European standards from Lloyd’s and other international regulation companies.
One aspect of pressure vessels that nearly every country agrees on is the pressure release mechanism for when the pressure vessel has too much built-in pressure. This pressure release system prevents the vessel from exploding and causing extreme damage to surrounding equipment and employees. This safety feature is known as the leak before burst regulation.
The leak before burst regulation works in such a way that when excessive pressure is applied on the vessel that could normally cause an explosion to occur, the vessel starts to crack instead. These cracks allow the liquid or gas inside the container to leak out slowly, which relieves the high pressure and prevents the unit from exploding. However, it does not prevent other safety risks, such as the risk of inhaling chemicals or harmful gasses during the release of the pressure.