PD 5500 is the pressure vessel design and fabrication code by the British Standards Institution. Like ASME, it received some updates in 2021 you’ll need to know if you are a fabrication manager or welder in the UK.
The Impact on the UK Leaving the EU on Pressure Vessel Safety Compliance
While these changes are minimal, they mainly come from the UK leaving the European Union. This means pressure vessels now fall under the UK Pressure Equipment (Safety) Regulations (PER) jurisdiction.
While within the EU, pressure vessels in the UK were regulated by the EU’s Pressure Equipment Directive (PED). While the PER replaces the PED, it is not entirely identical and there are some subtle differences you need to be aware of.
2021 Code Changes to PD 5500
The code changes to PD 5500 have come almost exclusively to Section 3. These changes include new guidance on weld area, openings and materials, which are beneficial to pressure vessel designers.
Changes to Section 3.5.4.9
This section is the alternative pressure area design method for nozzles. The weld area is now included as reinforcement as per the latest code revisions.
While this is a small change, it is a clear advantage to the designer using this method compared to the previous PD 5500 release.
Changes to Section 3.5.5.3.1(b)
Like in Section 3.5.4.9, this section makes the weld area included as reinforcement for openings and flat ends. Again, a huge benefit to pressure vessel designers.
Changes in Material Qualification
Another benefit of the 2021 PD 5500 code changes comes in material qualification. The code now clarifies when certain material groups should be used by making it more explicit, primarily in Section 3.4.2.2 when calculating the design stress limits for Category 3 vessels.
This means, instead of being instructed to use a general material for a design, the code will actually reference material groups where the allowable material is listed.
Design PD 5500 Compliant Vessels With Fabrication Software
With welding design and fabrication codes updating fairly regularly, keeping up with all the changes can be quite the challenge. By using a dedicated pressure vessel design software such as Finglow, however, complying with the recent PD 5500 changes as well as any future updates can be simple for you and your team.
Finglow is a software solution for designing pressure vessels that comply with PD 5500 standards. Designing outside the UK? Finglow also ensures you’re designing pressure vessels compliant with EN13445 or ASME Section VIII, Div. 1 and 2 as well.
Schedule your free demo today to see just how easy it is to design code-compliant pressure vessels.
Leave a Comment