ASME Stamp Does Not Ensure Quality Equipment
Most people believe that an ASME Code Stamp means “High Quality”. It does not.
There are a lot of junk pressure vessels and heat exchangers currently in service with ASME Code Stamps. I see them all the time. I’ve also reviewed enough internal inspections for API 970 Corrosion Control Documents (CCDs) to understand that this junk equipment is the source of many issues in process facilities. Corrosion loves to propagate around poor and incomplete welds. “No Radiography” is specified too often for critical service.
Shouldn’t the Authorized Inspector (AI) catch glaring mistakes? Sure, but many times the AI rubber stamps anything that passes hydrotest. That is why proper Source Inspection is a vital step that Owner/Operators should not skip. In fact, Source Inspection pays for itself by finding issues before hydrostatic testing. It becomes difficult and expensive to fix problems after an Owner/Operator has accepted the equipment into their facility because the fixes usually require an R-Stamp and another hydrotest.
I want to see what the quality control program looks like. I want to see what the non-conformance program looks like. I want to review the detailed calculations and compare them with my own calculations for critical components. Quality shops appreciate these checks because it helps improve quality.
Don’t assume all shops produce high quality equipment. Verify you are getting what you paid for by utilizing Source Inspection.
Use ASME PCC-1 Appendix O to Fix Leaky Flanges
What is ASME PCC-1 Appendix O?
It’s all about fixing your leaky flanges by taking a deeper look at the flange assembly bolt stress and ensuring the gasket is sealing properly. ASME PCC-1 Appendix O has a lot of stress values to look up (or calculate) and using “defaults” isn’t going to help you solve real world problems. It is important to know where to get some of the stress values you will need in order to properly determine bolt torque values using ASME PCC-1 Appendix O.
ASME PCC-1 Appendix O Required by PIP
Did you know that ASME PCC-1 Appendix O is required by Process Industry Practices (PIP)?
Yes, everyone knows that using ASME PCC-1 Appendix O reduces leaks and emissions.
Yes, everyone knows that using ASME PCC-1 Appendix O makes your facility safer.
Yes, everyone knows that using ASME PCC-1 Appendix O saves you money.
But not everyone knows that ASME PCC-1 Appendix O is required by PIP. Appendix O definitions like Target Assembly Gasket Stress, Sgt and Assembly Bolt Torque, Sb are being mentioned in courtroom arguments. It is a great time to start learning more about bolted flange joint assembly.
Please review PIP VESV1002 Part 4.4.3 Nozzles, Manways, and Flanges for more information regarding this PIP Specification for Vessels.
Minimum Thickness - ASME VS. PIP
Valid ASME Code designs rejected by Owner/Operators? It happens all the time when facilities enforce their own specifications, such as Process Industry Practices (PIP) specifications, on top of ASME Code rules.
Let’s take a look at a low consequence vessel designed with a ⅛” port cylinder thickness. Yes, the ASME Code allows for thicknesses as low as 1/16” per UG-16.2(d). However, the PIP Specification requires 3/16” minimum corroded thickness for all heads and shells. This means that facilities governed by the PIP Specifications need to adhere to the 3/16” minimum thickness and NOT the 1/16” thickness per ASME Code.
I love helping Owner/Operators enforce their own specifications because well defined specifications can help ensure facilities run safely and efficiently. Not sure where to start? Metalmark Engineering specializes in creating and maintaining the specifications for facilities just like yours!
ASME PCC-1 Appendix O Joint Assembly
Proper flanged joint assemblies depend on the interaction of the flanges, gasket, and bolts. ASME PCC-1 Appendix O investigates the interaction of flange stresses, gasket stresses, and bolt stresses to determine proper bolt torque values.
Why use Metalmark Engineering for your ASME PCC-1 Appendix O assessment?
Maximum Permissible Bolt Stress for the Flange, Sfmax calculation. Metalmark Engineering uses a complete Appendix 2 flange assessment with WRC 538 to determine the Maximum Permissible Bolt Stress for the Flange needed for ASME PCC-1 Appendix O.
Target Assembly Gasket Stress, Sgt determination. Metalmark Engineering works with gasket manufacturers and does not rely on assumed default values for Target Assembly Gasket Stress, Maximum Permissible Gasket Stress, Maximum Operating Gasket Stress, and Maximum Seating Gasket Stress.
Assembly Bolt Stress. SBsel determination. Metalmark Engineering determines the Assembly Bolt Stress and assesses if the upper bolt limit controls, if the lower bolt limit controls, or if the flange limit controls before determining if gasket seating stress is achieved.