Specification PD 5500:2009 issued

This major work specifies compliance requirements for unfired pressure vessels in the areas of materials, design, manufacture, inspection, testing and verification.

PD 5500 applies to unfired fusion-welded pressure vessels manufactured from carbon, ferritic alloy and austenitic steels, aluminium, copper and nickel, used in a wide range of process and energy industry applications.

This 2009 edition includes all the corrections and amendments made during the last three years to PD 5500:2006.

It is therefore technically equivalent to the 2006 edition, but the major benefit is that all the previous editing marks and page adjustments are now incorporated in the body text, resulting in this unmarked publication.

Revisions to material grouping designations in line with PD CR ISO 15608:2000 consist of: revisions to the calculation of tubesheet ligament efficiency, taking account of untubed area; improvements to the alternative method for loads on nozzles in cylindrical and spherical shells; the updating of references for new and revised European standards.

Enquiry cases have also been added, covering external loads on flanges, flexibility of the nozzle-vessel interface and guidance on alternative rules for nozzle reinforcement.

The term 'pressure vessel', as used in this specification, includes branches up to the point of connection to the connecting piping by bolting, screwing or welding, and supports, brackets or other attachments directly welded to the pressure containing shell.

The term 'unfired' excludes vessels that are subject to direct generated heat or flame impingement from a fired process.

It does not exclude vessels subject to electrical heating or heated process streams.

PD 5500 provides the basis for vessel design and manufacture for Pressure Equipment Directive (PED) compliance.

Key features are: a reference tool containing all the latest pressure vessel information; relevant dimensional diagrams and formulae for material determination; start of three-year cycle, including updates and enquiry cases; specification of requirements for materials, design, manufacture, inspection, testing and verification; basis for vessel design and manufacture for Pressure Equipment Directive (PED) compliance; all amendments, annexes and enquiry cases made during the last three years.

PD 5500:2009 supersedes PD 5500:2006, which is due to be withdrawn.