Hydrostatic Testing is the common way in which leaks can be found in pressure vessels such as pipelines, plumbing, cylinders, boilers, or tubes. Hydrostatic Testing is also used to make sure that pressure vessels are void of any leaks or manufacturing defects.
Hydrostatic Testing is important to maintain device safety and durability under normal operating pressures. When testing a pressure vessel using Hydrostatic Testing, all the information that is needed for testing is stamped onto the cylinder. The DOT information, serial number, manufacture, and manufacture date. Other info is also stamped on the cylinder such as the Rejection Elastic Expansion (REE) or how much the manufacture specifies the cylinder should expand before it is considered unsafe.
- Using Hydrostatic Testing helps maintain safety standards and durability of a vessel over time.
- Testing is used to continually re-qualify pressure vessels for safety
- Used to test gas pressure vessels such as a gas cylinder or broiler for leaks, rather than using gas which can explode under pressure
- The use of Hydrostatic Testing over gas pressure helps eliminate the possibility of explosion associated with gas pressure testing.
- Testing pressures are always more than normal operating pressured to give a good margin of safety, typically 150% of design pressure.
- Tolerance for failure is low, if Rejection Elastic Expansion (REE) is greater than 10% or not up to DOT, pressure vessels are condemned and deemed unsafe.
Hydrostatic Testing is carried out with the use of a Hydrostatic Pump. Hydrostatic Pumps are used to convert fluid power into mechanical power. These pumps are used as the source flow of the fluid. Many pumps and motors are reversible, but due to limitations of seals and rotating mechanisms the pumps may not allow reverse operation. Hydrostatic pumps are designed to operate at most desired speeds.
Hydrostatic Testing carries a very broad range of applications. A very simple test, and is still considered Hydrostatic Testing, is testing a garden variety water hose for any leaks within the hose. Hydrostatic Testing is also used in testing portable fire extinguishers. Over time the way the fire extinguisher is stored or used will have an impact on the extinguisher itself. Hydrostatic Testing is used to ensure the safety of the extinguisher. Buried high pressure oil and gas lines are tested to ensure there are no leaks within the system. These pipelines are pressurized to at least 125% of their Maximum Operating Pressure (MAOP).