Pipe questions - Induction Bends
Pipe questions - Induction Bends
(OP)
Can anyone answer any of the following questions:
Where I can find the specified ovality of a pipe? Is this something that is provided, from a table, or is there a rule of thumb?
In doing an induction bend calculation it asks for the set minimum wall thickness (%). This is different from the API positive and negative wall tolerances. Any idea what this is refering to?
Sizing plates, is there a table somewhere of standard plate sizes to choose from? If so can anyone direct me to it.
Thank you in advance!
Where I can find the specified ovality of a pipe? Is this something that is provided, from a table, or is there a rule of thumb?
In doing an induction bend calculation it asks for the set minimum wall thickness (%). This is different from the API positive and negative wall tolerances. Any idea what this is refering to?
Sizing plates, is there a table somewhere of standard plate sizes to choose from? If so can anyone direct me to it.
Thank you in advance!





RE: Pipe questions - Induction Bends
RE: Pipe questions - Induction Bends
Minimum wall thickness is the minimum wall thickness YOU can have and still safely contain the pressure according to your specific design code, pressure and material selection.
you'll find your pipe tables here,
http://www.pipingdesign.com
BigInch
-born in the trenches.
http://virtualpipeline.spaces.msn.com
RE: Pipe questions - Induction Bends
Now, as far as absolute ovalization induced or allowable e.g. by thereafter reeling or in various fashions and to various extents beam etc. bending such pipes or pipe sections, I would think that could be another matter, that could be influenced by your specific fabrication procedures and/or application etc. (that could be what Mr. BigInch is getting to). There is at least a discussion of the different ovalization expressions as previously discussed as well as some specific reeling etc. effects in some offshore applications in the paper at http://ww
RE: Pipe questions - Induction Bends
1. To minimize line-up problems on a tack and root weld when welding two joints together, in which case it only really need be specified for the pipe ends and the length between could be limited to some other value.
2. To predict the likely onset of collapse due to circumferential buckling from external pressure, most specifically applied by water pressure during offshore laying. Important because a small deviation from a perfectly circular section can reduce buckling resisting significantly from that of a section with a perfectly circular section.
3. Passage of a guaging pig (or any other tool) after construction to determine if there were any kinks or buckles that were missed by the visual inspection during laying or happened during the hydrotesting. For mechanical passage and to determine if the pipe section properties at any point might have been reduced to critical levels.
It could be considered for some design purpose to be in excess of the maximum permitted by the API pipe specs, in which case the maximum value allowed for such purpose should be supplied by the design engineer.
BigInch
-born in the trenches.
http://virtualpipeline.spaces.msn.com