Per ABSA IB10-004, referencing CSA B51-09 Clause 8.2, flexible hose assemblies don’t need to be CRN registered in Alberta if they are manufactured to RMA IP-2, which is the Rubber Manufacturers Association Hose Handbook. Note, if the rubber hose doesn’t comply with this requirement, then it must be CRN registered under a design code such as ASME B31.3.
The reason that this clarification was required is that the interpretation of the 2003 CSA B51 allowed for common industry practice to follow the approach of “no registration”, with no standards, no QA, etc…
The recent change in ABSA’s approach is that they will now register hose assemblies that comply with RMA IP-2, whereas before they refused to.
Yes, of course they’re allowed. Are there requirements for threaded connections?
ASME B31.3-2008–Process Piping
-Threaded Joints: Per ASME B31.3-2008 para.314, threaded joints are limited to Normal Fluid Service, and of course Category D Service. Tapered thread must conform to ASME B1.20.1 (NPT). There are notes in 314.2.2 covering additional requirements covering straight thread. Table 314.2.1 presents minimum thicknesses for male threaded components.
-Tapped holes: Per ASME B31.3-2008 para.309.3: depth of thread engagement in tapped holes, must be at least seven-eighths (7/8) times the nominal thread diameter, for pressure retaining bolting in metallic piping.
ASME VIII-1, 2010 ed–Pressure Vessels:
-UG-47 for braces and stays: thread engagement in blind hole must be a minimum of 1-1/2 times the nominal thread diameter.
-Table UG-43 specifies minimum number of pipe threads for connections.
-UG-43(g) gives a minimum thread engagement for blind tapped holes for studs: the maximum of either the nominal thread diameter or 0.75*(thread dia)(ratio of stud allow. stress/plate allow. stress), up to a maximum of 1.5*(nominal thread diameter).
These interpretations reflect how the Canadian Jurisdictions have typically interpreted these paragraphs. Please see ASME B31.3 or ASME VIII-1 for complete information, or contact Key Design Engineering. Remember that only the Jurisdictions can make binding code interpretations.
What are the Quality Management System requirements for a fabricator of Pressure Piping to be installed in Alberta?
- Canadian Fabricator in Alberta: Must have an Alberta Certificate of Authorization that covers the required Code of Construction, such as B31.1, B31.3, B31.5, or B.31.9, as applicable. Normally, except for Boiler External Piping per B31.1, an ABSA AI does not need to inspect the piping system, since the manufacturers are qualified to perform the inspections.
- Canadian Fabricator, not in Alberta: Either: A) Must hold a Certificate of Authorization from the local jurisdiction, that permits construction of pressure piping and doesn’t require inspection by a local jurisdictional inspector; or B) the piping must be inspected by a National Board commissioned jurisdictional inspector and certified using ABSA form AB-83F.
- Fabricator, not in Canada: The piping must be inspected by an Authorized Inspector employed by an Authorized Inspection Agency that is acceptable to ABSA. Form AB-83F must be submitted to the owner.
- Exception: Systems that are assembled by purely mechanical means (such as compression fittings) may be fabricated by a company with a limited-scope Quality Manual.
For additional information about Pressure Piping requirements at ABSA, please see AB-518, published in January 1, 2010. The information presented above has been summarized from Sections 3.1 & 3.6 primarily.
For CRN assistance, please contact Key Design Engineering.
What Code calculations can be done to validate a Tri-Clamp sanitary fitting for CRN registration in Canada? If they don’t have metal-to-metal contact on the outside rim, then they can’t be calculated per ASME VIII-1 Appendix-24 (24-1(b)). The only other options for determining MAWP are either a burst test per UG-101(m) or Finite Element Analysis (FEA) per ASME VIII-2, Part 5. Here’s a sample FEA report on a Tri-Clamp connection: Sample Tri-Clamp Report (1.2 MB)
For more information or for help with a CRN registration, contact Key Design Engineering.
Fatal Accident, Dec.28,2006: An aluminum water tank exploded, killing the welder assigned to fix it. The vessel supplied pressurized water for wash-down of ready-mix cement trucks, designed to be pressurized from the truck’s air-brake line.
The tank wasn’t considered as covered by ASME through a serious misinterpration of U-1(c)(2)(f), that essentially says that a water tank can contain an air cushion and still be excluded from the requirements of the ASME VIII-1 Code when the pressure is not more than 300 psi and the temperature is not more than 210F. ASME has stated their understanding of this paragraph as being the following: “…a vessel may be designed with a constant mass of air that serves as a cushion of pressurized air. When water enters the pressure vessel, the air pressure so created is directly related to the increase in water volume and the associated decrease in air volume in the vessel.” (see link below)
Some items highlighted in the engineer’s report are:
- no consideration for corrosion,
- no additional nozzle reinforcement or consideration for the knuckle-area stress
- improper weld types for attachment of nozzles and torispherical heads
- head material was much weaker than shell
The complete engineer’s report of the incident and this serious breach of Code rules is available from ABSA’s website.
Go to ACI Central and you can look up CRN numbers either directly by the number itself, or by the manufacturer. For each CRN, there is also a description of what the registration covers (part numbers, materials, design conditions, and Code of Construction).
For fittings, another useful piece of information is the expiry of the CRN. The availability of this information is unique to ACI and it is useful for finding components that have been registered Canada-Wide, as well as in the Atlantic provinces. Other than this system, it is difficult to check anybody’s registration number, unless they are willing to display their acceptance letter. Of course, pressure vessels will have it on the nameplate.
When the flanges are to be used on a piping system, then they must carry their own Canadian Registration Number (CRN). Even if they are built to a recongnized standard, such as ASME B16.5, they still need to be registered. On the other hand, if they are used on a pressure vessel, then they are covered by that vessel’s CRN.
Of course, if the piping system requires registration, then not only the flanges, but all the elbows, pressure gauges, pressure safety valves, bellows, weldolets, instruments, etc… need to carry their own CRN as well. Excluded from this is the pipe itself, that doesn’t need to be registered. See the CRN-Registered Components page for some examples of these available products.
When obtaining a Canadian Registration Number (CRN) for Boilers/Pressure Vessels/Fittings/Piping Systems in Saskatchewan, a new face and a new name will greet you. The registrations used to be handled by the Corrections, Public Safety, and Policing arm of the Government of Saskatchewan. Now it is all taken care of by the Technical Safety Authority of Saskatchewan. The fresh new face is found at http://www.tsask.ca.
Can submissions to obtain a Canadian Registration Number (CRN) be done either electronically or by fax? No. Jurisdictions still require that a paper copy be submitted. Sometimes supporting or additional required documentation can be added to the submission electronically, but certainly not the bulk of the submission. For fitting registrations, original copies of the Statutory Declarations are required (2 for most provinces, but check requirements).
How can sanitary fitting ferrules be handled for CRN registration? ASME VIII-1 doesn’t have calculations that specifically cover these types of clamped connections. Although Appendix-24 has a configuration that initially looks like it would satisfy the requirement, the scope excludes them because “hub faces shall be designed such as to have metal-to-metal contact outside the gasket seal diameter” (ASME VIII-1, 2007 ed, 2009b, 24-1(c)) In the case of many sanitary fitting configurations, a soft gasket covers the entire face. How can this be handled? Either it can be proven by a proof test per UG-101(m) or else by Finite Element Analysis (FEA) interpreted according to ASME VIII-2. Questions? Need help? contact http://keydesigneng.com
