Table 1A stress values for pipe
Table 1A stress values for pipe
(OP)
When we have several stress tables for similar pipe, which one do we choose?
For instance, SA-312-316 has the following:
Smls. & wld. pipe, 20,000 psi cold
Smls. & wld. pipe, 20,000 psi cold
Wld. pipe, 17,000 psi cold
Wld. pipe, 17,000 psi cold
We use these pipe for the ASME vessel to contain electric heater bundles. Our design temperatures are usually high.
For instance, SA-312-316 has the following:
Smls. & wld. pipe, 17,000 psi @ 600'F (note G5)
Smls. & wld. pipe, 12,600 psi @ 600'F
Wld. pipe, 14,500 psi @ 600'F (note G5)
Wld. pipe, 10,700 psi @ 600'F
Since this is a pipe body, would the following note apply?
Note G5: "Use of these stresses may result in dimensional changes due to permanent strain."
For instance, SA-312-316 has the following:
Smls. & wld. pipe, 20,000 psi cold
Smls. & wld. pipe, 20,000 psi cold
Wld. pipe, 17,000 psi cold
Wld. pipe, 17,000 psi cold
We use these pipe for the ASME vessel to contain electric heater bundles. Our design temperatures are usually high.
For instance, SA-312-316 has the following:
Smls. & wld. pipe, 17,000 psi @ 600'F (note G5)
Smls. & wld. pipe, 12,600 psi @ 600'F
Wld. pipe, 14,500 psi @ 600'F (note G5)
Wld. pipe, 10,700 psi @ 600'F
Since this is a pipe body, would the following note apply?
Note G5: "Use of these stresses may result in dimensional changes due to permanent strain."





RE: Table 1A stress values for pipe
jt
RE: Table 1A stress values for pipe
Thank you for this information.
What does it mean to exceed yield?
Imagine a 10" pipe body vessel with a 300# body flange on one end, a weld cap on the other end and 4" inlet / outlet connections on the side of the vessel.
Also, please may you consider higher design temperatures.
Heaterguy
RE: Table 1A stress values for pipe
If you look at the notes by the material you will find something like the following
You could use the higher values from 200°F to 1050°F if you could allow a little deformation. The stress values exceed 62 1/2% of the yield but not over 90% in this temperature range. This values are not to be used for pipe and flanges.
Any use of the stress values of this material above 1000°F requires that the Carbon be above 0.04%.
RE: Table 1A stress values for pipe
you can use the higher stress in the end cap.
Electric heaters are often use in higher temp aplications,
you may not be right at 600F and so not complying with the Code.
er
RE: Table 1A stress values for pipe
RE: Table 1A stress values for pipe
RE: Table 1A stress values for pipe
unclesyd, please clarify. Why are there two sets of high values and two sets of low values? Do you think this application will allow for a little deformation of the pipe body?
unclesyd, please clarify. You could use the higher values from 200°F to 1050°F if you could allow a little deformation. The stress values exceed 62 1/2% of the yield but not over 90% in this temperature range. This values are not to be used for pipe and flanges.
unclesy, we agree with the 1000 deg. F temperature limitation for SA-312-316. We would use SA-312-316H above 1000 deg. F.
GenB, this topic is not about flanges.
metengr, right on! Do you think we can use the higher stress values for pipe body vessels? Again, just the pipe body, not the flanges, weld caps, etc.
ijzer, we are leaning towards this direction. Thank you for your reply.
RE: Table 1A stress values for pipe
RE: Table 1A stress values for pipe
RE: Table 1A stress values for pipe
are you a student?
RE: Table 1A stress values for pipe
I think your question on exceeding yield has been well answered by unclesyd and metengr. As GenB and izjer both pointed out, you'd want to avoid the note G5 values for flange design. So... to sort out why there are four lines, focusing on notes G5, and G3 (but read the rest of them also!) and at temperatures where creep does not play a role:
Line 5: Applicable where some yield (deformation) is acceptible and where you don't have a weld joint efficiency to consider.
Line 6: Applicable where some yield is less tolerable and you don't have a weld joint efficiency to consider. eg: flanges, longitudinal tensile stress check.
Line 7: Applicable where some yield (deformation) is acceptible and where you must consider the joint efficiency of the welded pipe. Note G3 states that an E of 0.85 is included in these stress values. Not coincidentally, the allowable stresses in this line are... wait for it... 85% of the values in Line 5! You might use this line for circ stress calc's.
Line 8: Applicable where some yield (deformation) less tolerable and where you must consider the joint efficiency of the welded pipe. Again, note G3 states that an E of 0.85 is included in these stress values. Compare this with line 6. Not coincidentally, the allowable stresses in this line are... wait, wait... 85% of the values in Line 5.
So your basic decision making process will be to answer two questions for each evaluation (circ stress, long stress, etc) of each component: 1) Is some permanent deformation acceptible here? and 2) Does the calc involve the long seam and thus I need to account for the joint efficiency?
Once you've answered these two questions, your decision as to which stress value to use should be straightforward.
sjrfc Good point, but in this case all four lines are allowed up to 1500°F for VIII-1.
jt
RE: Table 1A stress values for pipe
jt
RE: Table 1A stress values for pipe
RE: Table 1A stress values for pipe
You can probably use 316 for your shell if you can allow the above mentioned distortion, as it will surly distort. If you can pick the pipe, get the higher carbon material. The distortion can take several forms usually the pipe will bulge and the hot nozzle centerlines will move. An additional point to consider is the 4" outlet flange as it will be at your process temperature. It should be at least Sch 80.
There are a couple of other points that need to be addressed like the process fluid, operating parameters and control scheme to stop overheating. As you are operating on the edge, the heater control scheme to prevent overheating from radiant heat and low flow are critical.
Is the process flow continuous?
RE: Table 1A stress values for pipe
The ASME pipe vessel can be vertical or horizontal. Typically the vessel is as hot as the process but in some high temperature gas applications, the vessel can be hotter than the process and even approach the heater bundle temperature.
The horizontal ASME pipe vessels typically have a fixed bolt hole saddle on the inlet side and a slotted bolt hole saddle on the outlet side. This allows the ASME pipe vessel to grow in length without bulging the ASME pipe vessel.
For instance, a 10" 300# 36 element heater bundle inside of a 10" sch 80 vessel: The 36 elements are evenly distributed inside of the vessel and the flowing fluid pulls heat off of the 36 heater elements. The vessels are typically 3 feet to 14 feet long. The heater bundle also has an over temperature sensor and controller.
Typically the inlet and outlet connections are perpendicular to the ASME pipe body and do not see any of the radiation from the heater bundle.
Based on the valuable information, within this post, which stress table would you use?
Smls. & wld. pipe, 20,000 psi cold, line 17
Smls. & wld. pipe, 20,000 psi cold, line 18
Wld. pipe, 17,000 psi cold, line 19
Wld. pipe, 17,000 psi cold, line 20
Note: line numbers are from 2001 ASME Table 1A
RE: Table 1A stress values for pipe
I just checked on our heaters (6" & 8") and we normally used the higher stress values, but this decision is tempered by our process and operating experience.
RE: Table 1A stress values for pipe
Are these Coded new construction vessels?
2001 Ed?