EEMUA PUB NO 168
A guide to the pressure testing of in-service pressurised equipment
|Publication Date:||1 July 2010|
EEMUA Publication 168 provides guidance on if, when and how pressure testing can be carried out on used pressure equipment and systems, based on a risk assessment and a safe system of work, before returning it to service. It gives a formal and clearly identifiable process which can be followed to manage and minimize the risks associated with in-service pressure testing. Some alternatives to pressure testing are also considered, and when it may be appropriate to employ them.
The Guide gives practical advice on the testing and inspection which may be carried out once the service life of pressure equipment has begun, but excluding the initial installation and commissioning. It is applicable to all types of nontransportable industrial pressure equipment and systems, including pressure vessels and pipework.
This Publication is aimed primarily at employees, managers and supervisors of pressure testing teams of both plant operators and owners. Engineers in other disciplines or with other responsibilities may also find the information useful.
Exclusions from Scope
The following topics are either excluded from the scope of this Publication or not dealt with in any great detail:
• Initial installation and commissioning of unused equipment is excluded.
• The pressure testing of atmospheric storage tanks is considered a special case, and therefore not included in the scope. The subject is dealt with in EEMUA Publication 159.
• Equipment that is subjected to heat for long periods, and/or that has been designed originally to operate in the 'creep' region is not normally pressure tested. For such equipment, alternative non-destructive testing (NDT) and inspection techniques are available. This Publication introduces the subject of testing and inspecting pressure equipment designed to operate in the 'creep' region before it is returned to service. However, it does not - at least in the current Edition - go into any great detail.
• Proof testing is excluded. This is a special kind of pressure test used to establish the maximum allowable working pressure of a system where this has not been calculated.
• Test waivers. Occasionally, it might be justifiable for equipment which would normally be pressure tested before returning to service - to have the pressure test waived. The pressure test waiver is considered a special case, and excluded from the scope. For guidance on the pressure test waiver, readers are referred to EEMUA Publication 223.
• Subsea equipment: special circumstances may apply to subsea installations.
Purpose of this Publication
Pressure equipment and systems, including pipework, are ubiquitous throughout industry. Europe's pressure equipment market alone has an annual turnover of many tens of billions of Euros. Once new pressure equipment is placed on the market, it will often remain in service for decades. During its long service life, the equipment may be subjected to many repairs, modifications and re-rating - requiring significant inspection and testing.
Pressure equipment in service presents hazards from stored energy, escape of harmful fluids, or both, and may result in significant loss of plant and harm to people - as, regrettably, some high profile accidents have shown.
If such disasters are to be avoided in the future, then every opportunity should be taken to learn from others. This Publication aims to contribute to the learning by capturing the combined knowledge and expertise of pressure equipment users across a range of industrial segments.