I work as a consultant for a pharmaceutical company that regularly allows their operators to access purged vessels. I was wondering if someone had come across an estimate for establishing a rough zone around an open manway. I am thinking of requiring SCBAs for this type of work but they do it so...
Recently, an operator saw an arch jump between a top bolt and the filter housing, a distance of about 2 inches. The filter is of spirally-wound cotton; it does not contact the wall of the filter housing. A long bolt runs axially through the middle of the filter housing holding the top head and...
I have an interesting problem for you. I am reviewing a rupture disc sizing of a chromatography column. Typically, these are packed beds with media or beads. There is a mobile phase that contains a solvent and a stationary phase. Solvents used in this column include ethanol and amyl acetate. By...
I have a 6" schedule 5 pipe running about 92' to the top of an absorption column. It carries cooling tower water to coils running the length of the column shell. Unfortunately, it vibrates about 1/8," so much so that I couldn't get a reading with a portable ultrasonic flow meter.
Someone has...
I have several vessels that were built in Europe and installed in our plant. We have calculations and the European stamps (on the vessel) but we are missing mill test reports. Are there any ASME Code VIII Div. 1 inspectors who can advise how we can certify these vessels. Our alternative is to...
I just got a request for some design work. I have Pipe-Flo Pro, a hydraulic program but I need Hysys or ChemCAD because the process involves natural gas/lights liquefaction, compression, and separator design and specification. Hysys, as we all know doesn't offer short term leases. ChemCAD does...
I'm specifying a probe for larger horizontal tanks. Unfortunately, none of tank nozzles have the same length. The client wants the same probe for each tank to reduce the number of probes of different lengths. My current plan is to specify long so that I can have the piper specify the section of...
I am developing a complex de-ethanizer column to simulate what Henry Kister described in his book, (Case study 2.10) "Distillation Troubleshooting." I set up the column initially with Peng-Robinson with feed at 80 F, pressure at 350 psig. Initially, I disconnected the side-streams going back to...
I am being asked to write a specification for a hand pump. This will be a crank-driven lobe pump or diaphragm.
Does anyone know what API specification applies?
I generally have had the best experience with sock filters proceeded by a duplex strainer. A sock can get down to 0.5 micron and a strainer can go to 37 microns. What do you think? Which is better, sock or cartridge?
I am investigating the failure of a differential thermal relief valve on a twin-seated plug valve used in an outlet from butane sphere. The relief valve failed to open and the back (bottom) of the valve popped open; a semi-circle of bolts were punched out; one was severely bent, a couple were...
Does anyone know of any best practices for lining up flow from a petroleum products tank to a pipeline for a pipeline that carries many products?
And, does anyone know of any criteria for ordering new pipeline valves to reduce the risk of cavity contamination from use with multiple products in...
We're having a lively discussion in our department where and when to apply a dynamic simulation for sizing a relieve valve. I've argued that dynamic is not necessary for a fire scenario since this is a steady-state process. It has been suggested that a dynamic simulation is an absolute necessity...
I have a difficult problem. Liquid propane is sent to two pipelines or a tanker truck rack. The suction pipeline to the pumps is uninsulated. There is no pressure control on the propane bullets. The pumps are fed 5 at a time to a pump through a single 4" sch 80 bottom connection for each bullet...
I have been asked to troubleshoot an LPG system. There are 4 racks of 7' dia. bullets, 5 bullets to a rack. The five bullets in a rack feed a booster pump at a rate of 600 gpm with a 4" line from each bullet. On hot days, above 70 F with the sun out, the pumps vapor-lock. When the bullets drop...
I have a tough problem involving an alkylation-acid mixing tee. Hysys does not have a good mixing tee program except what is embedded in an Aspen hydraulics sub-sheet. I would like to use this sheet but am having trouble getting it to cooperate. I would use AFT Fathom or Korf but the physical...
A client is asking whether he can weld heat treated ASTM 106 Grade B to non-heat treated ASTM 106 Grade B. This is > 10,000 ppm wet H2S service.
I suggested a flange-joint to preserve the treatment but he insists on welding.
How will welding affect the heat treatment?
Is there any recourse...
As we know, car-sealing is a common term for allowing maintenance for relief valves. Now, I have a client using terms like safety car-seal open and safety car seal closed.
I was wondering if anyone knows any legal definition devining the difference between a car sealed open valve and a safety...
I'm working with a client's P&IDs. One drawing shows me an atmospheric tank that is tagged, "out of service." The tank was in service with gasoline. The pump suction line is blinded but the fill line is not. In fact, the P&ID shows the fill line valve as open. The conservation vent has been...
I am working on a project to develop P&IDs for a pipeline company. They're telling me that OSHA does not have jurisdiction over the pipeline or even the tankfarm facilities. When I checked on DOT documentation they defer pressure relief work and other mechanical integrity tasks to OSHA. When I...
