Elastic Follow-up Can Result in Failures in Systems that Comply with Piping Code Rules

The analysis procedures in the Code essentially assume that the strain range in the system can be determined from an elastic analysis. That is, strains are proportional to elastically calculated stresses. The stress range is limited to less than two times the yield stress, in part to achieve this. However, in some systems, strain concentration […]

Continue Reading

Fluid Catalytic Cracking (FCC) Transfer Line Flexibility – Analysis and Design Considerations

FCC’s are complex units – and the design of their transfer lines has some unique considerations. While many of the lines are refractory lined to permit construction with carbon steel piping, some sections are hot walled, at temperatures well into the creep range, for the purpose of balancing thermal expansion or, in the case of piping […]

Continue Reading

Reduced Toughness Properties of Some Modern Carbon Steels Create Brittle Fracture Risk

Changes in steelmaking practice are reported to be causing some carbon steel piping components that are assumed by ASME Codes to behave in a ductile manner at ambient temperatures, to behave instead in a brittle manner.  Barry Messer from Fluor made a presentation on this subject at the Spring 2016 meeting of the ASME B31.3, […]

Continue Reading
Becht default post image

Designing Elevated Temperature Equipment with Internal Pressure

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 […]

Continue Reading

What is the Future of ASME B31.3, Appendix P?

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 […]

Continue Reading
Tags: ,
Becht default post image

What is Bellows Pressure Thrust?

Pressure thrust is present in all pressurized piping systems. It is simply the gage pressure times the inside area of the pipe. It acts at changes in direction, such as elbows, and at changes in pipe cross section, such as reducers. Pressure thrust is normally carried as an axial load by the pipe. However, inclusion […]

Continue Reading
Tags:

The Difference Between ASME B31.3 Appendix X and EJMA Fatigue Curves for Bellows?

Bellows vendors will often quote two different cycle lives for their bellows. One is in accordance with ASME B31.3, Appendix X. The other is in accordance with the Standards of The Expansion Joint Manufacturers Association. The latter provides a significantly higher cycle life. The EJMA bellows fatigue curve is a best fit curve based on […]

Continue Reading
Tags: ,
Becht default post image

Leadership

I was asked to participate in an engineering career development panel session at the 2013 ASME Pressure Vessel and Piping Conference which was held in Paris, France. I elected to talk about what engineers can do to improve their leadership skills. I am including some of the introductory material in this blog; the full presentation […]

Continue Reading
Let Becht Turn Your Problem
Into Peace of Mind