PVEng started in 1999 as a one person company located in the founder’s basement. The first paying job was the design of an ASME rated water filter 10 feet diameter by 15 feet tall. A faxed pencil sketch was turned into an AutoCAD drawing with Excel calculations. Other early jobs were for calculations only or review and P. Eng. stamp of calculations and drawings by others.
4,000 jobs later a lot has changed. Fax has been replaced by email. Calculations that used to be done in Excel are now done in industry standard programs like Compress, Design Calcs, PV Elite and Nozzle Pro. AutoCAD has been replaced with SolidWorks unless required by our customers. Finite Element Analysis has been added to solve problems that cannot be solved by the application of code rules. And the company of one is now nearing twenty. However, through all the changes, the mix of jobs has remained the same. While ASME code design is still our core focus, we now work to more ASME standards: I, IV, VIII-1, VIII-2, B31.1 B31.3 and others such as API-620 and 650. Although we use commercial design software where we can, we also have an extensive library of spreadsheets for applications where nothing else will work.
This sample is a typical ASME VIII-1 audit vessel. We discuss what happens during an ASME audit, how many sample vessels need to be built to justify more than one ASME stamp and calculation verification.
Material properties used in section VIII are taken from Section II-D and is fairly extensive, through a range of temperatures. Here topics dealing with many material variables can be found. As well as some guidance in sorting through the numerous materials in Section II-D and how to ensure the proper one is used for calculations.
The articles below will hopefully provide some clarification on code weld requirements listed in ASME VIII-I. This initially simple topic often leads to confusion when it comes to efficiencies in calculations.
The ASME nozzle area replacement rules cannot be taken on their own. ASME code book rules outline how one can cut a hole in a vessel as long as the nozzle attached to it replaces the lost area.Here is some guidance on code rules and issues surrounding the attachment of round and non-round nozzles to the vessel.
A variety of components analyzed using code rules. The results are then discussed comparing the difference between component types.Both the calculation and FEA methods are used. Calculation set are available for download at the end of each article.
Pressure Vessel Engineering reviews and registers many designs a year which are subject to a variety of loadings. As external pressure calculations start out more complex than internal, naturally we then receive many more questions. Here we hope to address many of our most commonly asked questions and provide working samples to help explain loading cases.
The following articles are a collection of calculation packages relating to a variety of vessel ranging from simple to complex. Each package is a complete with drawing and calculation set.
Requirements for lethal service are scattered through VIII-1, the code cases and the interpretations. We collected all these requirements in one place.