24 Jul, 2024
ISI

In the UK, Hydrostatic Pressure Testing is essential in maintaining the highest quality of safety standards for pressure-containing pipework and vessels used in housing and buildings, industrial equipment and components, and many other kinds of infrastructure.

Read on to learn the benefits of hydrostatic pressure testing for your organisation and why testing is necessary for regulatory compliance in the UK.

What is Hydrostatic Pressure Testing?

A hydrostatic pressure test is a type of pressure test in which pressure-containing pipework, vessels, components, and systems are purposefully pressurised to evaluate their integrity and suitability for future use to minimise the potential risk of harm to workers, wildlife, and the public.

These tests are often necessary for verifying the design, material quality, strength, and sealing arrangements to ensure the longevity and reliability of pipelines and other pressure-containing infrastructure during the development phase.

Hydrostatic pressure testing may also involve an ultrasonic thickness measurement test, which can be used to measure the wall thickness of a vessel that has experienced excessive corrosion which compromises its strength and increases its risk of failure.

What Are the Benefits?

Because hydrostatic pressure testing generates a smaller amount of stored energy and poses less risk to workers, it is one of the preferred methods of testing pressure-containing infrastructure. In this type of assessment, a liquid is pumped into the system and then pressurised with gas or air to test whether the material will crack or burst.

This process can determine if the vessel can hold and withstand the amount of pressure required for its intended use efficiently and safely. Hydrostatic pressure testing may also be used to detect leaks before systems are set to operate, minimising dangerous compound emissions, and eliminating harmful leaks.

Not carrying out a hydrostatic pressure test on your pressure-containing pipework, vessels, and systems can increase the likelihood of potential risks, including:

  • Reduced efficiency
  • Leaks
  • Corrosion
  • Damage to the system
  • Risk of explosion

What Equipment & Procedure is Used?

Hydrostatic testing is carried out by filling vessels with a liquid – usually water – at a pressure of at least 125% of the maximum operating pressure (MOP) for a minimum of 4 continuous hours. If the pipework is not visible, then an additional 4 hours at a pressure of at least 110% of the MOP may be required.

This procedure allows engineers to identify leaks and their causes, as well as confirm how strong and reliable each welded seam is and will continue to perform. Any serious defects can then be immediately reported, followed by a full summary and review including impartial advice about future steps.

What Are the Hydrostatic Pressure Testing UK Regulatory Standards?

Under the Health and Safety at Work Act (1974), employers are required to provide a safe workplace for their employees. One of the regulations established to enforce this is the PSSR 2000 (Pressure Systems Safety Regulations 2000).

PSSR requires that before the use of qualifying pressure equipment, pressure systems must be checked according to a Written Scheme of Examination (WSE). These regulations aim to prevent serious harm caused by the hazard of stored energy, whether due to the failure of a pressure system or one of its components.

Applications of Hydrostatic Pressure Testing

At ISI, we carry out comprehensive on-site or in-house hydraulic testing and implosion testing to a maximum pressure of 10,344 bar / 150,000 psi on an extensive range of pneumatic and hydraulic equipment such as:

  • Pipework
  • North Sea gas / oil pipework
  • Pressure vessels
  • Shot blast vessels
  • Accumulators
  • Heat exchanges
  • Air receivers
  • Calorifiers
  • Hot water boilers
  • Steam boilers
  • Petrochemical installations
  • Hydraulic / pneumatic fittings / assemblies
  • Prototypes / new products

For pressure vessels in use, a hydrostatic pressure test is required either at periodic intervals, following a statutory inspection where significant corrosion is identified, where you have concerns about the performance of older equipment, or following an incident, damage, or repair to the pressure-containing infrastructure.

Hydrostatic Pressure Testing by ISI

At ISI, our Hydrostatic Pressure Testing and PSSR Inspections ensure compliance through a thorough examination and regulatory WSE documentation.

Our wide range of Hydrostatic Testing equipment and experienced specialist engineers will assist you in maintaining the highest quality safety standards for you and your employees.

Please get in touch for guidance from our hydrostatic pressure testing specialists. Alternatively, visit our PSSR pressure system inspection services page for more information.