Hydrotest

A hydrostatic test is a way in which pressure vessels such as pipelines, plumbing, gas cylinders, boilers and fuel tanks can be tested for strength and leaks. The test involves filling the vessel or pipe system with a liquid, usually water, which may be dyed to aid in visual leak detection, and pressurization of the vessel to the specified test pressure. Pressure tightness can be tested by shutting off the supply valve and observing whether there is a pressure loss. The location of a leak can be visually identified more easily if the water contains a colorant. Strength is usually tested by measuring permanent deformation of the container. Hydrostatic testing is the most common method employed for testing pipes and pressure vessels. Using this test helps maintain safety standards and durability of a vessel over time. Newly manufactured pieces are initially qualified using the hydrostatic test. They are then re-qualified at regular intervals using the proof pressure test which is also called the modified hydrostatic test.[citation needed] Testing of pressure vessels for transport and storage of gases is very important because such containers can explode if they fail under pressure.

You should also mention that hydrotesting is inherently safer than pneumatic testing - which is one of the main reasons it is the preferred test. As water is incompressible, if there is a leak - the instant the source of pressure is shut off the internal pressure will drop to zero. Additionally, if the vessel fails under test, there is a lot less energy (blast) to dissipate than if air or nitrogen had been used.

does anybody have asme b31.8 procedure for hydrotest? thanks in advance