Max span for 250NPS
Max span for 250NPS
(OP)
How about 48m!
h ttp://www. flickr.com /photos/ke vink2008/2 535271195/
This is 250NPS (10") pipe hot water in Sch80 and XS. Design pressure 20 bar @ 180C
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This is 250NPS (10") pipe hot water in Sch80 and XS. Design pressure 20 bar @ 180C





RE: Max span for 250NPS
Amazing! Where is that?
Regards,
Bill
RE: Max span for 250NPS
RE: Max span for 250NPS
This is not new practice. Seen this done in the UK many years ago to span across a motorway, except there were two lines approaching from two direction which were tied together to give some lateral stability.
RE: Max span for 250NPS
Must not be much wind or earthquakes there.
http://virtualpipeline.spaces.msn.com
"What gets us into trouble is not what we don't know, its what we know for sure" - Mark Twain
RE: Max span for 250NPS
The earthquake design loads are quite high .85g static equilivant.
We used modal anayisis for the Earthquake design. First period is quite long.
Wind loads are upto 95% allowable stress.
We started with a design with two loops. Then one braced loop with stay wires. Then we found a conbination of pipe that did not require stays.
RE: Max span for 250NPS
What's inside the pipe gas, oil, water?
http://virtualpipeline.spaces.msn.com
"What gets us into trouble is not what we don't know, its what we know for sure" - Mark Twain
RE: Max span for 250NPS
Thank you for the technical update
steve
L S THILL
RE: Max span for 250NPS
never seen that before!
Do you assess this piping by hand, with software like CAEPIPE or CII, or more detailed FEA?
yours,
RE: Max span for 250NPS
RE: Max span for 250NPS
http://virtualpipeline.spaces.msn.com
"What gets us into trouble is not what we don't know, its what we know for sure" - Mark Twain
RE: Max span for 250NPS
The pipe is constructed with mitres. Was fabricated and isulated on the river bank then lifted into place with one lift from far side.
RE: Max span for 250NPS
Anyways, it looks very cool. At first glance (and second for that mater) I would question the controlling occasional load being wind at 95% when you have a static seismic loading of 0.85g. What was the greatest miter angle in the piping?
RE: Max span for 250NPS
The loop ends is on private land and normal pipe bridge or straight span would have the same temptation to climb. The owners may yet fence the ends.
If we used static loading for EQ then it would have been 0.85g but we used modal design and an acceleration spectrum. Wind does not combine with EQ loads.
Mitres are only a few degrees.
RE: Max span for 250NPS
RE: Max span for 250NPS
In that regard you are right in that what you are showing of a pipe crossing in the form of an arch is in fact far from "new practice", and you may be interested in an installation depicted in the foreground of the picture at http://ww
RE: Max span for 250NPS
When researching what we could do for this loop we did find other examples using twin pipes and even a patent for such. Nothing as old as your pictures though. Thanks.
RE: Max span for 250NPS
I am very, very curious about the piping details encased in the concrete anchors on either end..
Did you include some kind of trunion structure or welded plate design within the concrete ?
How about a local analysis of the welds at the concrete/steel interface ?
It seems to me that, depending on the piping design code, such a design might fail a "local stress check" at the anchors before it would fail bending stress in the mid-span...
My opinion only
-MJC
RE: Max span for 250NPS
The stresses in the 500 pipe are not high. We included the trunions in the pipe stress model.
Kevin