FAILURE MODE – When an explosion (either a subsonic deflagration, or a supersonic detonation) occurs in a metallic vessel, one of three things can happen: Case 1 – Containment: The vessel can contain the explosion, elastically as if nothing happened, or with plastic bulging. Case 2 – Rupture: The vessel can rupture, without ejecting fragments. […]
In addition to the many clarifications, updated references to codes and standards, updates to basic allowable stresses, and added listed materials, there are several substantive changes to the 2014 Edition of ASME B31.3, Process Piping. These changes are: Category M Fluid Service The definition was revised in the 2014 edition to provide better guidance on […]
Becht Engineering, Nuclear Services Division, has completed a finite-element numerical study of two proposed Code Cases for ASME III Division 1 Subsection NH, Class 1 Components in Elevated Temperature Service. They are: “Satisfaction of Strain limits for Class 1 Components at Elevated Temperature Service Using Elastic-Perfectly Plastic Analysis” and “Calculation of Creep-Fatigue for Class […]
Are You In Compliance??? In construction today, it seems like the rules and regulations are changing everyday. There is good reason for this. As an industry we are getting smarter about addressing safety in the work place. Recently, I searched the OSHA website looking for information regarding the requirements for a “Lift Director.” Upon entering […]
Nonmetallic composite wrap repairs are wraps comprising two constituents: A fabric woven from a fiber such as graphite or glass A thermoset polymer such as a two-component mix epoxy resin. This material is also referred to as fiber-reinforced polymer (FRP). These repairs can be liners wrapped inside, or jackets wrapped over a corroded pipe. There […]
If the behavior of discontinuity stresses due to pressure is not properly understood in elevated temperature design, unconservative designs can result. One particular issue with pressure stresses is the behavior of the discontinuity bending stresses. An example of discontinuity stresses would be with a pipe welded to a flange. When pressured, the pipe will radially […]
So, you think you know what load case combinations to use for your ASME Section VIII, Division 2, Part 5 analysis to satisfy Protection Against? Common sense says to follow to Code rules in Table 5.3 – but do you fully understand what that means? And, what loads should you use to satisfy Protection […]
Appendix P was written to introduce piping flexibility analysis rules that are more suitable for computer piping flexibility analysis, in contrast to the rules in the base Code which were written when piping analysis was done by hand calculations. Most of the elements of Appendix P have been, or are proposed to be, added to […]
While there are currently no explicit rules on how to perform a finite element analysis (FEA) if you are doing so in support of an ASME Section VIII, Division 1 vessel, there is good practice. Regarding rules, all you have is from Article U-2(g), which says: This Division of Section VIII does not contain […]
The pressure vessel and piping jurisdiction in Alberta, Canada is ABSA – the pressure equipment safety authority. All pressure equipment as defined by the provincial Safety Codes Act must be registered with ABSA. I have been involved in registering piping systems and pressure vessels in this, my home jurisdiction. The focus of this blog […]
