Bleed Ring Design Responsibility Q&A

In this space, some questions posed by customers and industry are published in case others have similar questions. Anonymity is preserved. Check back for updates and new correspondence.

Dear Cammar,
Does ABSA require that bleed rings be registered or not? I don’t see anything in the pressure equipment safety regulation that exempts bleed rings from having CRN number registration.
I look forward to hearing from you.

IM Concerned

Dear Concerned,
Thanks for your email.
ABSA reportedly does not require CRN number registration for bleed rings – in general. See page 5 of for more information. But each circumstance should be considered on its own merits. For example, a pressurized cylinder sealed with o rings between two ASME B16.5 flanges and held together with threaded bars connecting the flanges, is not a bleed ring. The line between a bleed ring and something else can be blurry and open to interpretation.

What is always necessary is a safe design. Instead of your question, a better question would be: can the device with the pressure port included, safely withstand the proposed pressure? ‘Safely’ means within the factor of safety specified by the code of construction as a minimum. Regardless of whether pressure equipment needs a CRN number or not, the design always needs to meet the minimum requirements of available codes and standards, and the design must thereby provide an acceptable safety margin that the designer, vendor, and end user can responsibly attest to.