You need to look at the difference between the slip and non-slip liquid. The difference is the volume of liquid that would be removed if you pigged the line. Also, if you did not include every elevation change greater than the OD of the pipe, the program will not give you an accurate liquid...
Cross-country pipelines rarely require a formal stress analysis with programs such as Caesar. An above-ground fuel gas line may be designed as restrained or unrestrained. For either the design should consider the extremes of ambient and operating temperatures. Design and hydrotest pressures also...
The effects of liquid holdup will be the result of a number of factors and is very complex in nature.
The ratio of liquid to gas is an important factor as well as the relative densities of the two phases, as well as the mixture velocity. Another important factor is the inclination of the pipe...
With considerable experience in the subject of erosional velocities, I offer the following memo drafted to address the subject as pertains to an ammonia pipeline:
Many companies, have in their process piping go-bys or rules-of-thumb, references to a maximum velocity of fluids in piping. This...
There is not any in-line instrumentation capable of accurately measuring two-phase flow of any sort, that I am aware of.
In the process of designing 80 km of steam pipeline, my solution has been to measure the vapor phase at the destination (in this case, 250 injection wells) and subtract it...
25362:
The higher pressure system I spoke of was also at higher temperatures as well, since ammonia is liquid at those conditions.
Your right for -28°F but the wave speed does go down for higher temperatures. This chart, however, does give much higher wave speeds even at higher temperatures...
Thanks to all who have contributed here. I now have the info I need to complete my calculations. I had found a value at another location listing 4900 ft/sec, but didn't think it was accurate, since that's higher than water! The wave speed is a measure of the compressibility of a fluid and I was...
I'm again in the process of doing surge studies. This time on an anhydrous liquid ammonia line (-28°F., ~50 psig). I can't seem to find a source for the wave speed (acoustic velocity) of liquid ammonia nor can I find the bulk modulus for ammonia. Can anyone point me to a reference for either of...
The University of Kentucky civil and mechanical engineering department has developed comprehensive and inexpensive hydraulic programs dealing with slurry and network flow as well as transient flow (surge analysis). They offer regularly scheduled training sessions and siminars on the use of the...
These methods will tell what what the composition of the material is, but won't tell you what grade it is. The process of manufacture also affects the strength of materials, such as cold-working and other techniques. The only way to test the strength of materials is in destructive tensile and...
AMSE B31.3 should only be used if the line is totally conatained within the boundaries of of single plant. If the line is cross-country and/or crosses public lands or roads, then the provisions of ASME B31.8 and CFR Part 192 will apply.
But I agree that any line over 2" should be butt-welded.
Tremolo,
No, I have not found a suitable commercial package. I have started on a spreadsheet, but think it's going to take something more powerful. I have steam functions for a spreadsheet, but not for a BASIC program.
For what it's worth, most two-phase flow calculations thru orifices are only accurate if the two phases are in one of the homogeneous flow regimes (i.e., mist flow or distributed bubble) thru the orifice. For all the other flow regimes (stratified, wavy, annular, plug, or slug flow)two-phase...
We use normal carbon steel for all liquid propane service. The charpy requirements for steel are based on its strength under full pressure. If you depressure the pipe to get it cold, there is no load on the pipe and thus, there are no strength or charpy requirements. Just don't strike the cold...
