Hydrostatic test
The pressure test, pressure test is also performed on pressurized components that are intended for the storage and propagation of fluids to provide proof of sufficient strength and the detection of leaks.
Pressure tests are part of the acceptance test and are usually performed as a hydrostatic pressure test. To the pressure conduit of the pressure vessel or other body parts with water, air or process gas (e.g., natural gas, nitrogen ) to be filled. Subsequently, the pressure is slowly increased up to the level of the test pressure. The test pressure then acts a certain amount of time allowed to fall during which time the pressure within the specified tolerance and the object to be inspected may / lose air, no water / gas. The height of the test pressure during the pressure test is determined according to the relevant regulations and is usually higher than the permissible operating pressure.
- Pressure testing can be carried out as a gas or as a combination pressure test Wasser-/Gasdruckprüfung. When the gas pressure test safety procedures should be carried out.
- As part of the periodic inspections according to regulation on classified installations, the required strength test is performed usually as a hydrostatic pressure test.
Visually, it is checked whether impermissible plastic deformations caused or leakage especially at welds, fasteners or to connections (flanges, threaded fittings, etc. ) are present.
Requirements for pressure testing are included in the applicable regulations such as
- Level of test pressure
- To-use fluid
- Information to increase the pressure and holding time of the test pressure
- Assessment criteria
- Documentation
For pipelines, among other visual pressure testing, pressure differential tests and stress pressure tests are carried out. The pressure test has three tasks: strength test, leak test, stress relief.
Rules and regulations, the information on the pressure test include:
- Pressure Equipment Directive Annex I, point 3.2.2 and No. 7.4
- EN 13445-5, Unfired pressure vessels - Part 5: Inspection and testing
- AD 2000 HP 30
- EN 13480-5 Industrial piping - Part 5: Testing
- EN 12952-6 Water-tube boilers and auxiliary installations Part 6: Inspection during construction
- EN 12953-5 Shell boilers - Part 5: Testing
For Germany:
- DVGW 469 06/2010 conducting pressure tests
- VD TÜV 1051
The pressure test shall be in accordance with a part of the periodic inspections. Ordinance on Industrial Safety of systems requiring monitoring.
- For pressure vessels, industrial piping and other pressure containing parts according to the information in accordance with the Pressure Equipment Directive Annex I, point 7.4 is determined.
- Pressure testing of pipelines for Gas-/Wasserversorgung be according to DVGW 469 with the 1.1 - performed or 1.5 times operating pressure - / 1,3 - / 1,43.