Most of us have seen a gate valve installed in piping, and 99% of the time, we want to see the valve handle in the VERTICAL-UPWARD position. However, when we need to install an “intervening valve” in the relief path, which ASME allows, we may/should see the valve handle(s) in the Horizontal or below Horizontal […]
ASME has allowed dual PRD systems ever since I started in process safety back in 1993. These systems usually have a Rupture Disc (RD) BEFORE the Pressure Safety Valve (PSV). This is usually done to protect the more expensive and more complicated PSV from the corrosive process gases. Although I never managed a PR system
For decades, we used Appendix M-5 in Section VIII as our design basis for having intervening/stop valves before and/or after a Pressure Relief Device (PRD). But in 2021 (amid the global pandemic), ASME published its new Section XIII, Rules for Overpressure Protection. We now use Appendix B of this new ASME section when we have a design
I talk a lot about inspecting welds/flanges and then pressure testing and leak testing our piping. However, there is more to this story. Inspecting our piping actually begins before it is installed. 341.4.1 Examination – Normal Fluid Service
It is true that not all flanges and threaded joints have to be visually examined. However, this exemption is seriously limited. (4) a sufficient number of threaded, bolted, and other mechanical joints selected at random to satisfy the examiner that they conform to the applicable requirements of para. 335. Here is the qualifier…
On September 19, 2002, Employee #1 was painting one (1) of six (6) tanks containing carbon dioxide when three (3) of them suddenly exploded. He was killed. The tanks were originally built as railroad tank cars for liquefied petroleum gas and they were not designed to store carbon dioxide.
“Why did they have a Rupture Disc and a Relief Valve together?” As I alluded to in my post regarding CBS’s update, this arrangement is fairly common but comes with some very SPECIFIC requirements. These requirements can be found in: But the top four (4) requirements, we as safety engineers should be looking for in
I have shared the ASME and NBIC “code” requirements for these arrangements and it has already stirred a number of debates/questions; of which the API has offered some excellent guidance on this design. (emphasis by me)
It has grown tiresome, but it remains a teachable moment, to debate “engineers” who want part of ASME/NBIC to be the gospel and other parts not so much. The ammonia refrigeration industry just can’t seem to grasp the critical need in their “Common PRV Header Design” v.s. having more “holes in the roof” (as they
I have upload my REVISED Car Seal Program and the PowerPoint that goes with it to the Document Library – Chemical Process Safety folder.
I see many contractors still arguing that Pressure Testing and Leak Testing are the same test. This is incorrect, as I have often discussed in my ramblings on this website. This post breaks down the requirements of the most common “leak test,” called the “bubble test.” ASME B31.3 refers us to ASME BPVC Section V
The 2018 IFC has some great design requirements for flammable liquids (as does NFPA 30). Abiding by this 2018 IFC, Chapter 57 would provide a much higher degree of safety as compared to meeting OSHA’s 1910.106. So I have broken down and discussed these IFC requirements for those looking to improve their flammable liquid piping
