Division 2/Appendix 46 Assessments
Why use Metalmark Engineering for your Division 2 assessment?
Speed in Proving Viability: We quickly determine if your pressure vessel or heat exchanger is a good candidate to use Division 2 rules*.
Calculation Accuracy: We are experienced in using the latest software tools to generate Division 2 ASME Code calculations.
Cost Savings: Due to the differences in the Division 1 and Division 2 Code computations, designs using Division 1 Code calculations may require additional material than designs using Division 2 Code calculations. Taking advantage of these differences may result in significant cost savings.
Lead Time: Pressure vessels and heat exchangers designed using Division 2 rules may require significantly fewer welds; designs with fewer welds can significantly reduce your lead time.
Process Experience: We are experienced in identifying API 571 damage mechanisms in process equipment and piping. From material selection to long-term maintenance plans, we are experienced in supporting the integrity of your process equipment.
Appendix 46 for Large, Non-Radial Nozzles
Don’t let large, non-radial nozzle designs ruin your design schedule. Pass nozzle reinforcement calculations and stay ASME Code compliant by using Appendix 46.
A recent client had a big problem with a large nozzle. The 10’ (3m) vessel diameter and 42” (1m) nozzle diameter pushed the Division 1 nozzle calculations into Mandatory Appendix 1-7. The nozzle design would have easily passed the Appendix 1-7 calculation at the design pressure of 50 psi if it were radial. But it wasn’t. The 2” inch offset was non-negotiable and pushed it outside of Appendix 1-7 due to failing Appendix 1-7(b)(1).
This represented a perfect case for using the Appendix 46 nozzle rules. Appendix 46 combines Division 2 nozzle design rules with Division 1 allowable stresses. The more accurate numerical method combined with the high safety factor gives an ASME Code compliant solution that satisfies most regulators. Ask your regulator about using Appendix 46 as direct-replacement nozzle rules and solve problems like large, non-radial nozzles within minutes without employing FEA.
Is your Renewable Natural Gas (RNG) or Nuclear project trying to go fast? Metalmark Engineering works at turnaround speeds to help your team get your project up and running while adhering to the latest Codes and Standards.
Division 2 Rules are Safer and Save Money
Did you know you can design safer and save money using ASME Division 2 rules instead of Division 1?
There are many ways to take advantage of the higher allowables and more accurate numerical methods in Division 2. One such method to consider is using the Bildy Rules instead of Area of Replacement for nozzle design.
Take a look at this simple nozzle internal pressure case:
Design Pressure = 290 psi (2000 kPa)
Design Temperature = 475°F (246°C)
Nozzle Material = SA-106 C Smls Pipe
Nozzle Size = NPS 12 Sch 140
The Division 1 vessel does not pass the design condition of 290 psi (2000 kPa) @475°F (246°C).
The Division 2 vessel passes the design condition of 290 psi (2000 kPa) @475°F (246°C).
I recommend against designing with nozzle reinforcing pads whenever possible. This is one simple example where a nozzle reinforcing pad is avoided by using Division 2.
Use Division 2 Nozzle Rules with Appendix 46
Are you using the Division 2 nozzle rules yet?
I know a lot of Owner/Operators are afraid of using the Division 2 rules because they are weary of using higher allowable stresses. Did you know that you can apply the lower Division 1 allowables with the Division 2 rules by using Appendix 46 in Division 1 designs? This means engineers like me can still save big money where the Division 2 rules offer a clear advantage. This is especially evident in nozzle design where the Bildy rules often avoid extraneous nozzle reinforcement compared to the Division 1 area-of-replacement rules.
Save Money using ASME Division 2 Rules
Can you save money using ASME Division 2 rules instead of Division 1?
There are many ways to take advantage of the higher allowables and more accurate numerical methods in Division 2.
Take a look at this simple external pressure (vacuum) case:
Outside Diameter, Do = 60.75” (1543 mm)
Thickness, t = 0.375” (9.53 mm)
Unsupported Length, L = 264” (6706 mm)
The Division 1 vessel does not pass the vacuum condition of 14.7 psi (101 kPa).
The Division 2 vessel passes the vacuum condition of 14.7 psi (101 kPa).