Haven't done this in a while. I have 10-year and 100-year accelerations and wind loads, but I'm not sure how to translate that into cycles or account for cumulative damage from cycles at lower accelerations. In other words, should I be using some sort of statistical distribution (I have a dim...
I have a pipeline project that involves welding some X65 pipe to some X52 fittings. The bore is the same, and these are both S-1 materials. One of my client's inspectors commented that there may be a shadow on the x-ray that will prevent him from seeing flaws. I got this 3rd hand, so I'm...
I'm a pipe stress engineer, but I often have to deal with stresses on nozzles, clips, et cetera. I am not up-to-date on the latest ASME BPVC Section VIII. I have access to the code itself, but I don't know if reading hundreds of pages is the best use of my time when I am not in the business of...
I have recently done a super-rushed analysis of shaking pipe caused by slug flow. I used a harmonic analysis, calculating the forces at the elbows from the product of density, slug velocity squared and cross-sectional area. In a spectral analysis, one would derive a dynamic loading factor to...
At our facility, we are allowed the option of working four 10-hour days and being off on Friday. Our company was sold to a much larger company that works a regular 5-8 schedule. We are continuing our schedule for now, but I was just wondering how common the 4-10 schedule is at other companies.
I have a small project that ties into an underground pipeline. The pipe will be at ambient temperature, so do I need to do a pipe stress analysis? I know how to analyze buried pipe, I just need to know whether it needs to be done here. Other information - the pipe will be connecting to a...
The company I'm working for is failing. We have laid off about 2/3 of our work force and closed several offices. I have already survived one office closure, but I think my current office will close within 3 months, and despite my technical competence I don't know whether I will survive the...
I am analyzing a slug flow case. We observe that an elbow gets slammed every 3-5 seconds and displaces less than 1" in one direction, and even less in the other two. The estimated rise in pressure due to the slugging has been given to me by the process department. I multiplied this by the...
I'm working on a line that's coming out of the radiant section of a furnace. Since the nozzle is not restrained, I have to model some of the coils in order to have a decent anchor point. The piping is bent in a helical coil with about 12 rings. the coil is supported by u-bolts, 4 per ring...
I am looking for a resource to learn how to evaluate stresses on the shell of an API 650 tank due to attachments. Specifically, right now I'm working on a gantry that follows the upper rim of a floating roof tank.
I am looking for a resource to learn how to evaluate the stresses in a tank shell due to attachments. We are adding about 10' to a walkway that runs along the upper edge of the circumference of the tank. I don't find anything quite comparable in my pressure vessel handbooks.
I'm about to do stress analysis on some piping connecting to a new API 650 tank. I am planning on modeling the piping in Caesar II or Auto Pipe, and making the face of the flange of the nozzle a displaced anchor to account for settlement. I'm thinking there should be hot and cold installed...
I have a client that wants to use butane as a blanket gas for an API-650 floating roof tank containing #6 Fuel Oil. Does this sound right? I usually see something inert like nitrogen being used, not a flammable hydrocarbon.
I've been asked to check whether or not we can lift a vessel we are replacing by its top nozzle. Is there any part of the Boiler & Pressure Vessel Code that explicitly deals with this? Anything I should watch out for? Any advice would be appreciated, as this is the first time I've been...
Does anyone have specific information about recommended line sizes for tying in 50# steam to use for valve jacketing? What I'm looking for, is how many 1/2" supply lines I should add to an existing 1" header versus tying in directly to the upstream 2" header, or even going all the way back to...
