My first thread. I am interested in potentially building a pressure vessel that will be capable of 5000 psi at ambient temp. Approx 24" ID x 16" height. Water with anti-corrosion additive will be used as fluid. The bottom can be fixed but the top needs to be easily opened and closed for isostatic pressing operation. I have looked at commercial builders and the cost and lead time is extremely high/long. I have been able to research some of the design parameters and constaints and I understand the forces. I believe my requirements fall into the ASME VIII div 2 standards. I have found a copy in the city library. Are there web sites, documents, video or specific books that I might read that will help me smoothly through this engineering quagmire? I am a mechanical engineer with fluids background but never worked on this type of project. Maybe there are economical "pre-engineered" designs that I might be able to copy. Can anyone steer me?
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Pressure Vessel Design for Isostatic Pressing
- Thread starter solidpoly
- Start date
InspectorByDay
Mechanical
solidpoly,
Yes, it is probably best to apply the rules of Division 2 to this design. You can use Division 1, but you might have to take into consideration some additional loadings that are not addressed in that Code.
If this is going to be a Code-stamped item, you are going to want to make sure the Section VIII Division 2 which you have found at the library is of the latest Edition (2007) and Addenda (2009). But since you're considering building this in-house, I'm guessing there are no pressure vessel laws in your Jurisdiction and therefore do not need to have this Code stamped.
Having said this, most commercial books on pressure vessels take a Section VIII Division 1 approach to design. But there are a couple out there worth looking into:
First, anything written my Maan Jawad is overwhelmingly insightful. His books are not cheap, however, and I recommend maybe finding this at the library. These are:
Guidebook For the Design of ASME Section VIII Pressure Vessels
Structural Analysis and Design of Process Equipment
These books tackle design problems using both Division 1 and Division 2.
As far as canned designs, I doubt you'll find anything in the pressure range you're considering. Perhaps I could be of assistance if you could give me some more insight into the project.
Yes, it is probably best to apply the rules of Division 2 to this design. You can use Division 1, but you might have to take into consideration some additional loadings that are not addressed in that Code.
If this is going to be a Code-stamped item, you are going to want to make sure the Section VIII Division 2 which you have found at the library is of the latest Edition (2007) and Addenda (2009). But since you're considering building this in-house, I'm guessing there are no pressure vessel laws in your Jurisdiction and therefore do not need to have this Code stamped.
Having said this, most commercial books on pressure vessels take a Section VIII Division 1 approach to design. But there are a couple out there worth looking into:
First, anything written my Maan Jawad is overwhelmingly insightful. His books are not cheap, however, and I recommend maybe finding this at the library. These are:
Guidebook For the Design of ASME Section VIII Pressure Vessels
Structural Analysis and Design of Process Equipment
These books tackle design problems using both Division 1 and Division 2.
As far as canned designs, I doubt you'll find anything in the pressure range you're considering. Perhaps I could be of assistance if you could give me some more insight into the project.
A 5000 PSI pressure vessel isn't that much of design challenge but in your case it's the closure that presents the problems and cost.
A 24" dia HIPing pressure vessel is in the size range of production vessels.
Your pressure of 5000 psi appears to me to be low.
You make no mention of the application of any heat.
inspectorbyday,
I looked at 2 sites of HIP vessel manufacturers where the EU one mentions ASME Sect VIII and the US one mentions ASME Sect VIII Div 3.
A 24" dia HIPing pressure vessel is in the size range of production vessels.
Your pressure of 5000 psi appears to me to be low.
You make no mention of the application of any heat.
inspectorbyday,
I looked at 2 sites of HIP vessel manufacturers where the EU one mentions ASME Sect VIII and the US one mentions ASME Sect VIII Div 3.
InspectorByDay
Mechanical
You know, you can use any of the divisions (1, 2, or 3) from Section VIII to design a pressure vessel. Code even mentions that each subsequent division does not intend to place a limit on the preceding one.
Having said that, for isostatic processes (which are typically beyond the 10 ksi range), Division 3 is simply the better fit.
If solidpoly is looking for a vessel with a design pressure of 5 ksi then Division 2 is the better fit.
However, Division 1 is also an acceptable Code...it is really up to the end user or Jurisdiction.
If it were me, I'd use Division 2 for a design pressure of 5000 psi.
Regards.
Having said that, for isostatic processes (which are typically beyond the 10 ksi range), Division 3 is simply the better fit.
If solidpoly is looking for a vessel with a design pressure of 5 ksi then Division 2 is the better fit.
However, Division 1 is also an acceptable Code...it is really up to the end user or Jurisdiction.
If it were me, I'd use Division 2 for a design pressure of 5000 psi.
Regards.
- Thread starter
- #5
Thanks to all for replies.
I am in NY and I am sure I need to have a code stamp. And what I've read it seems a daunting task unless you have some experience. Tomorrow I plan to visit the library to begin review of the ASME Code and see if I can find the 2 books InspectorByDay recommended. I'm not sure about the 2009 addendum.
I have had success cold pressing the material I'm interested from 3000 to 5000 psi. No heat is required. But unforunately all my work has been in small presses <6" ID. I need to build a larger press to evaluate my tooling configuration in larger part sizes. If 24" ID becomes a difficult task, I'm willing to drop size to ~12" ID.
Questions:
1 - It's clear I need to review Section VIII Div. 1&2, I'm not sure yet the pros and cons for me to design and validate to Div 1 vs. Div 2. My understanding is I do not need to meet Div 3 due to my projected max op pressure of 5 ksi.
2 - What is the key design parameter(s) that should drive me to Div 1 or 2 or 3. Obviously code conformance is primary but I am a very small business owner with limited budget... so investment is significant factor. I would prefer a design that is quicker to build.
3 - Do I end up in Div 3 if I decided to go to 7 ksi?
4 - Closure designs that are easy to open and close is also important. At this point I have seen and operated 4 different closure systems at press manufactures that include full threads (ACME thread?), interrupted buttress threads, large perpendicular pin to lock flat plug head and plug head with yoke support that goes completely around vessel. They all offer some advantage. But at this point I'm more likely to pick the easiest to least costly to manufacture to allow my research and development to continue. I will have to machine components outside my facility. Any guidance on this topic?
Thank you in advance for your help. I really appreciate comments.
I am in NY and I am sure I need to have a code stamp. And what I've read it seems a daunting task unless you have some experience. Tomorrow I plan to visit the library to begin review of the ASME Code and see if I can find the 2 books InspectorByDay recommended. I'm not sure about the 2009 addendum.
I have had success cold pressing the material I'm interested from 3000 to 5000 psi. No heat is required. But unforunately all my work has been in small presses <6" ID. I need to build a larger press to evaluate my tooling configuration in larger part sizes. If 24" ID becomes a difficult task, I'm willing to drop size to ~12" ID.
Questions:
1 - It's clear I need to review Section VIII Div. 1&2, I'm not sure yet the pros and cons for me to design and validate to Div 1 vs. Div 2. My understanding is I do not need to meet Div 3 due to my projected max op pressure of 5 ksi.
2 - What is the key design parameter(s) that should drive me to Div 1 or 2 or 3. Obviously code conformance is primary but I am a very small business owner with limited budget... so investment is significant factor. I would prefer a design that is quicker to build.
3 - Do I end up in Div 3 if I decided to go to 7 ksi?
4 - Closure designs that are easy to open and close is also important. At this point I have seen and operated 4 different closure systems at press manufactures that include full threads (ACME thread?), interrupted buttress threads, large perpendicular pin to lock flat plug head and plug head with yoke support that goes completely around vessel. They all offer some advantage. But at this point I'm more likely to pick the easiest to least costly to manufacture to allow my research and development to continue. I will have to machine components outside my facility. Any guidance on this topic?
Thank you in advance for your help. I really appreciate comments.
InspectorByDay
Mechanical
solidpoly,
You are correct, you will not have to meet Section VIII Division 3.
Here are the pros and cons of each Division:
VIII-1:
Pros:
Cheaper
Proven viability
Thousands of U-stamp Manufacturers available
Cons:
Cook booked
Thicker, heavier wall thicknesses (typically)
Fatigue not addressed in Code.
VIII-2:
Pros:
Engineered
Might allow thinner material
May consider fatigue
Cons:
Fewer Manufacturers available
Pricier
Overall, I would look at what your needs are and base my decision off of that.
If fatigue is a true concern over the life of the vessel, then I recommend using VIII-2. If it is not, then VIII-1 will save you a buck and serve your purposes just fine.
I'm not well-informed of HIP needs, but my guess is that fatigue analysis might need to be taken into consideration for the design.
Regards.
You are correct, you will not have to meet Section VIII Division 3.
Here are the pros and cons of each Division:
VIII-1:
Pros:
Cheaper
Proven viability
Thousands of U-stamp Manufacturers available
Cons:
Cook booked
Thicker, heavier wall thicknesses (typically)
Fatigue not addressed in Code.
VIII-2:
Pros:
Engineered
Might allow thinner material
May consider fatigue
Cons:
Fewer Manufacturers available
Pricier
Overall, I would look at what your needs are and base my decision off of that.
If fatigue is a true concern over the life of the vessel, then I recommend using VIII-2. If it is not, then VIII-1 will save you a buck and serve your purposes just fine.
I'm not well-informed of HIP needs, but my guess is that fatigue analysis might need to be taken into consideration for the design.
Regards.
InspectorByDay
Mechanical
Almost forgot, but if you are interested in obtaining your own Certificate of Authorization I recommend getting in touch with a well-reputed Authorized Inspection Agency such as HSB Global Standards ( An AIA can provide you with lots of good information.
I will caution you, the cost of getting a Cert. of Authorization is typically not justified unless you are looking to get into the business. For a Section VIII-1 U-stamp, you are looking at around $12K - $15K once you buy all the required Code books, pay for the Authorized Inspection and Joint Review (which will also include the review team's meals and hotel accommodations), qualify welding procedures and buy and all the materials needed to build the little demonstration vessel.
Regards.
I will caution you, the cost of getting a Cert. of Authorization is typically not justified unless you are looking to get into the business. For a Section VIII-1 U-stamp, you are looking at around $12K - $15K once you buy all the required Code books, pay for the Authorized Inspection and Joint Review (which will also include the review team's meals and hotel accommodations), qualify welding procedures and buy and all the materials needed to build the little demonstration vessel.
Regards.
I would try the surplus/excess equipment route to get started. It would allow proof of concept for your process and allow more time for generating a design.
Below is just one of many people that have used/new high pressure equipment available.
I would make personal contact with each company as it has been my experience you can pickup a few leads in this manner.
Below is just one of many people that have used/new high pressure equipment available.
I would make personal contact with each company as it has been my experience you can pickup a few leads in this manner.
Justolejim
Industrial
I think Division 1 of the Code goes to only 3000psi - I think he would have to design the unit to division II - The lower unit could be machined from a single billet of SA 516-70 eliminating the stress relieving - Charpy Impact testing and Preheating and full x-ray of any seams. The top could be a bolted integral flange. Any openings various problems
Have a good day
Have a good day
Justolejim
Industrial
Oh -- An authorized inspector is 3rd party disinterested party - Don't think fabricator qualifies
Have a good day
Have a good day
Just to keep things clear, Justolejim's statement about Section VIII Div. 1 being limited to 3000 psi internal pressure is incorrect. There is no pressure limit on Section VIII Div. 1, Div. 2, or Div. 3. Having said that, yes, there is a statement in Div. 1 regarding additional considerations if you exceed 3000 psi. This has been discussed in these fora plenty of times.
Keep in mind that Div. 1 also requires fatigue evaluation. It just doesn't tell you how to do it.
It seems to me that this is a Div. 2 or a Div. 3 candidate. I would lean towards Div. 2 if for no reason other than having a larger group of Code shops to choose from. There are not very many Div. 3 shops.
Since solidpoly has zero experience with pressure vessel design, I'd suggest he does not meet the requirements as stated in the foreword to design this vessel. For that matter, he does not have the experience to write a User's Design Spec. If he PE stamps the UDS, he could be liable for practicing out of his area of competence. Just because I hold a PE stamp in Mechanical Engineering does not mean I'd be qualified to design the brake system on a car and I shouldn't go around PE stamping things like that.
So solidpoly - I recognize that you stated that you are a small business owner with a limited budget and that it is very tempting to DIY this project. I'll ask you to consider a few things: Why do the commercial guys who design these for a living take so long to design 'em? If something goes wrong, will you be comfortable stating your qualifications for ordering/designing/fabricating this vessel to a jury? Are you really willing to gamble your livelihood on this?
Buying used equipment may be a reasonable approach. Just be sure if its Div. 2 or Div. 3 that you process the change of location and use as an Alteration with your vessel competent and experienced PE and AI and jurisdiction as appropriate.
I recognize I may sound a bit harsh. Let me point out that I do not consult for private parties and thus have nothing to gain. I'm just trying to point out that the approach it seems this project may be taking may eventually get people hurt, so I figured its worth some keyboard time.
Please consider hiring an experienced, competent consulting engineer to help guide you through this process. Some things just need to be done right.
jt
Keep in mind that Div. 1 also requires fatigue evaluation. It just doesn't tell you how to do it.
It seems to me that this is a Div. 2 or a Div. 3 candidate. I would lean towards Div. 2 if for no reason other than having a larger group of Code shops to choose from. There are not very many Div. 3 shops.
Since solidpoly has zero experience with pressure vessel design, I'd suggest he does not meet the requirements as stated in the foreword to design this vessel. For that matter, he does not have the experience to write a User's Design Spec. If he PE stamps the UDS, he could be liable for practicing out of his area of competence. Just because I hold a PE stamp in Mechanical Engineering does not mean I'd be qualified to design the brake system on a car and I shouldn't go around PE stamping things like that.
So solidpoly - I recognize that you stated that you are a small business owner with a limited budget and that it is very tempting to DIY this project. I'll ask you to consider a few things: Why do the commercial guys who design these for a living take so long to design 'em? If something goes wrong, will you be comfortable stating your qualifications for ordering/designing/fabricating this vessel to a jury? Are you really willing to gamble your livelihood on this?
Buying used equipment may be a reasonable approach. Just be sure if its Div. 2 or Div. 3 that you process the change of location and use as an Alteration with your vessel competent and experienced PE and AI and jurisdiction as appropriate.
I recognize I may sound a bit harsh. Let me point out that I do not consult for private parties and thus have nothing to gain. I'm just trying to point out that the approach it seems this project may be taking may eventually get people hurt, so I figured its worth some keyboard time.
Please consider hiring an experienced, competent consulting engineer to help guide you through this process. Some things just need to be done right.
jt
Justolejim
Industrial
ASME Section VIII Division I Section U-1 d
States "The rules for this Division have been formulated on the basis of Design principles and construction practices applicable to vessels designed for pressures not exceeding 3000psi (20685kPa) see the next paragraph for the deviations from these requirements that are required . Gosh unless There is a new edition and mine is out of date and that could be possible. Anyone have a 2009 and the revisions to the code?
States "The rules for this Division have been formulated on the basis of Design principles and construction practices applicable to vessels designed for pressures not exceeding 3000psi (20685kPa) see the next paragraph for the deviations from these requirements that are required . Gosh unless There is a new edition and mine is out of date and that could be possible. Anyone have a 2009 and the revisions to the code?
Justolejim
Industrial
One Could Check with Mr. Chuck Withers Assistant Chief of The National Board and get the National Board of Boiler and Pressure Vessel Underwriter's consensus opinion.
Justolejim – The issue of pressure limits on the three Divisions of Section VIII have been discussed in several previous threads. One example is thread794-209259. I don’t see that its worth rehashing the topic – in particular since the original poster solidpoly is likely heading down the Div. 2 or Div. 3 road anyway, and there’s no need to steer this thread elsewhere. The U-1(d) paragraph hasn’t changed and there seems to be no record on the Committee radar which would indicate that a change is being discussed. Interesting to note that the Foreword is likely to get some changes.
In any case, welcome to the Forums! It seems that you have enthusiasm and knowledge that will add useful material to the discussions. Just be sure to get A09 ;-). You could do us a favor by going to the “My Stuff” tab and selecting “My Profile” and putting some info in the “Tell other members about yourself” box. Sometimes it’s useful to know the background of a responder to better understand their perspective. You can see my profile simply by clicking on the “jte” at the top of this response.
jt
In any case, welcome to the Forums! It seems that you have enthusiasm and knowledge that will add useful material to the discussions. Just be sure to get A09 ;-). You could do us a favor by going to the “My Stuff” tab and selecting “My Profile” and putting some info in the “Tell other members about yourself” box. Sometimes it’s useful to know the background of a responder to better understand their perspective. You can see my profile simply by clicking on the “jte” at the top of this response.
jt
InspectorByDay
Mechanical
Justolejim,
The 3000 psi pressure mentioned U-1(d) is not a design limitation of VIII-1, but rather a parameter beyond which it might not fully address design issues. Keep reading the rest of the paragraph you cited and you will see that design pressure above 3000 psi does not preclude Code stamping IAW VIII-1.
jte, I disagree that VIII-1 requires fatigue analysis unless UG-22 loadings can only be addressed by such calculations. If you are talking cyclic loads...maybe. In which case, VIII-2 can be used to satisfy VIII-1 requirements per U-2(g). However, it is up to the user to provide this information to the Manufacturer.
The 3000 psi pressure mentioned U-1(d) is not a design limitation of VIII-1, but rather a parameter beyond which it might not fully address design issues. Keep reading the rest of the paragraph you cited and you will see that design pressure above 3000 psi does not preclude Code stamping IAW VIII-1.
jte, I disagree that VIII-1 requires fatigue analysis unless UG-22 loadings can only be addressed by such calculations. If you are talking cyclic loads...maybe. In which case, VIII-2 can be used to satisfy VIII-1 requirements per U-2(g). However, it is up to the user to provide this information to the Manufacturer.
inspectorbyday (engineer by night?)
I think we’re in violent agreement here…
Div. 1 requires that cyclic loadings due to pressure, thermal, equipment mounted (e.g. mixers), or other mechanical loadings be considered. UG-22 and UG-22(e). It does not prescribe how to determine whether a formal analysis is required nor how to perform one. Most vessels will reasonably see more than one pressure cycle in their lifetimes.
Thus we head off to U-2(g). Most folks will then head to Div. 2 for guidance on evaluating whether a fatigue analysis is required and if so, how to perform the analysis. Most of the time the old AD-160 / new 5.5.2 exemptions can be applied and we are done considering fatigue loadings – no calculations need be run.
Some claim that no fatigue analysis/design is ever required for a Div. 1 vessel. My point is that just because Div. 1 throws the designer into U-2(g) does not exempt the designer from considering cyclic loadings and, if necessary, designing the vessel accordingly. As you note, it is up to the user to ensure that the fabricator is aware of the nature of the loadings. That’s part of the argument that I’ve heard in favor of requiring a UDS for Div. 1.
See also… Int VIII-1-07-47 in Vol 59 (2009)
jt
I think we’re in violent agreement here…
Div. 1 requires that cyclic loadings due to pressure, thermal, equipment mounted (e.g. mixers), or other mechanical loadings be considered. UG-22 and UG-22(e). It does not prescribe how to determine whether a formal analysis is required nor how to perform one. Most vessels will reasonably see more than one pressure cycle in their lifetimes.
Thus we head off to U-2(g). Most folks will then head to Div. 2 for guidance on evaluating whether a fatigue analysis is required and if so, how to perform the analysis. Most of the time the old AD-160 / new 5.5.2 exemptions can be applied and we are done considering fatigue loadings – no calculations need be run.
Some claim that no fatigue analysis/design is ever required for a Div. 1 vessel. My point is that just because Div. 1 throws the designer into U-2(g) does not exempt the designer from considering cyclic loadings and, if necessary, designing the vessel accordingly. As you note, it is up to the user to ensure that the fabricator is aware of the nature of the loadings. That’s part of the argument that I’ve heard in favor of requiring a UDS for Div. 1.
See also… Int VIII-1-07-47 in Vol 59 (2009)
jt
InspectorByDay
Mechanical
jte
I agree. Making a Design Spec. mandatory in VIII-1 would solve the lingering doubt over whether UG-22 loadings have been sufficiently addressed by the Certificate Holder.
It seems VIII-1 has always considered such due diligence to be a contractual issue rather than a Code issue, which I feel is detrimental to safety and reliability. Those of us in the industry (like you and me) are fully aware that design parameters are not always investigated properly, especially in OEM scenarios.
The recent addition to the Non-Mandatory Appendix is welcomed, but I feel it still falls short.
Thanks for the Interp. reference.
Regards.
I agree. Making a Design Spec. mandatory in VIII-1 would solve the lingering doubt over whether UG-22 loadings have been sufficiently addressed by the Certificate Holder.
It seems VIII-1 has always considered such due diligence to be a contractual issue rather than a Code issue, which I feel is detrimental to safety and reliability. Those of us in the industry (like you and me) are fully aware that design parameters are not always investigated properly, especially in OEM scenarios.
The recent addition to the Non-Mandatory Appendix is welcomed, but I feel it still falls short.
Thanks for the Interp. reference.
Regards.
racookpe1978
Nuclear
24 inch ID with a 16 inch length (Assume tangent length).
Since high temperature and corrosion resistance are not issues, why not use pipe components rated to that pressure: that would take care of the end cap and flange issue with standard parts. (Granted the 24 inch pipe components are OD, not id, but the cost of the slightly larger components compared to fabricating everything would permit a larger standard diameter.) It would be built to P-vessel code (not pipe code) -as mentioned above - but with standardized parts the fabrication itself would appear to become simplified.
Since high temperature and corrosion resistance are not issues, why not use pipe components rated to that pressure: that would take care of the end cap and flange issue with standard parts. (Granted the 24 inch pipe components are OD, not id, but the cost of the slightly larger components compared to fabricating everything would permit a larger standard diameter.) It would be built to P-vessel code (not pipe code) -as mentioned above - but with standardized parts the fabrication itself would appear to become simplified.
- Thread starter
- #19
I'm finally back with some thoughts.
Again I want to thank everyone for excellent feedback and discussion. This site has been extremely helpful.
I have completed many days of research at the local city library and nearest University engineering library. I did find Section VIII Div. 1 & 2 at city library. Significant documents! Unfortunately they did not have Section II (Materials).
InspectorByDay: I did also find (and read) the 2 books you recommended and another called High Pressure Vessel (Freyer/Harvey). All 3 were excellent. I took notes and copied critical pages. Again a lot to digest.
UncleSyd: I tried to find surplus/excess vessel with no luck. Lots of vessels but with poor or no quick open/close capability.
I have concluded that I'm going to downsize my origin project to 12" ID since this is still R&D for me and also to save cost. Additionally, I am convinced that I need to stay away from any welding of the vessel or head due to extensive NDT reqts and other design limitations.
At this point I think the easiest and safest design for me to construct with the required SF is to use a seamless pipe vessel with plug style heads along with off the shelf seal system (O-ring or seal package offered by multiple suppliers). I believe a yoke system to keep the vessel heads in place will be the easiest and lowest cost to analyze and build. All the other quick close/open systems have complex welding or machining required.
After all the research and above comments, I've concluded that I can use either Div-1 or Div-2. I believe Div-1 requires SF=4 and Div-2 requires SF=3. There are basic forumulas for Thin and Thick wall vessel designs that can be used based on thickness iterations and target design pressure. And if you know the C factors for flat plates/plugs you can easily determine the thickness of the vessel heads. My plan is to design and build to ASME BPVC requirements. Collect the needed material documentation as I progress. If this press pans out during my R&D and I want to use it on the factory floor, I would then spend the $ to get it properly stamped.
So, I have completed numerous calculations based on the following materials. Vessel: A-106 Seamless Pipe Grades B&C and 4140 Seamless Pipe. Vessel Heads: A-105 Forge and A-36. These materials seem readily available and most economical. Unfortunately I do not have the "official ASME BPVC" allowable, yield and ultimate strengths for these materials to be 100% confident in my thickness and SF calculations. I also found on a previous Eng-Tip post that 4140 cannot be used since the C content is greater than 0.3%. But my understanding is this only applies if you are considering welding.
1 - Can I use 4140 for the vessel if I do not intend to weld the closure head?
2 - Are there any other economical materials I should be considering?
3 - Are any of the above materials a mistake to use?
4 - My calculations (with questionable allowable and ultimate strength numbers) have resulted in thickness that do not result in SF > 4 when using the basic Div-1 formula for vessel wall thickness. I got 2.0" thickness using Div-1 formulas for one of the vessel materials above but the (Ultimate stress)/(Wall stress) is less than 4. Do I have to increase wall thickness to get > 4 SF? Maybe with the correct strengths my calculations will be ok.?
5 - Relative to potential future stamp: can I simply collect the material specification on each part as I proceed? Is the correct document the MTR? Any guidance here?
Again I want to thank everyone for excellent feedback and discussion. This site has been extremely helpful.
I have completed many days of research at the local city library and nearest University engineering library. I did find Section VIII Div. 1 & 2 at city library. Significant documents! Unfortunately they did not have Section II (Materials).
InspectorByDay: I did also find (and read) the 2 books you recommended and another called High Pressure Vessel (Freyer/Harvey). All 3 were excellent. I took notes and copied critical pages. Again a lot to digest.
UncleSyd: I tried to find surplus/excess vessel with no luck. Lots of vessels but with poor or no quick open/close capability.
I have concluded that I'm going to downsize my origin project to 12" ID since this is still R&D for me and also to save cost. Additionally, I am convinced that I need to stay away from any welding of the vessel or head due to extensive NDT reqts and other design limitations.
At this point I think the easiest and safest design for me to construct with the required SF is to use a seamless pipe vessel with plug style heads along with off the shelf seal system (O-ring or seal package offered by multiple suppliers). I believe a yoke system to keep the vessel heads in place will be the easiest and lowest cost to analyze and build. All the other quick close/open systems have complex welding or machining required.
After all the research and above comments, I've concluded that I can use either Div-1 or Div-2. I believe Div-1 requires SF=4 and Div-2 requires SF=3. There are basic forumulas for Thin and Thick wall vessel designs that can be used based on thickness iterations and target design pressure. And if you know the C factors for flat plates/plugs you can easily determine the thickness of the vessel heads. My plan is to design and build to ASME BPVC requirements. Collect the needed material documentation as I progress. If this press pans out during my R&D and I want to use it on the factory floor, I would then spend the $ to get it properly stamped.
So, I have completed numerous calculations based on the following materials. Vessel: A-106 Seamless Pipe Grades B&C and 4140 Seamless Pipe. Vessel Heads: A-105 Forge and A-36. These materials seem readily available and most economical. Unfortunately I do not have the "official ASME BPVC" allowable, yield and ultimate strengths for these materials to be 100% confident in my thickness and SF calculations. I also found on a previous Eng-Tip post that 4140 cannot be used since the C content is greater than 0.3%. But my understanding is this only applies if you are considering welding.
1 - Can I use 4140 for the vessel if I do not intend to weld the closure head?
2 - Are there any other economical materials I should be considering?
3 - Are any of the above materials a mistake to use?
4 - My calculations (with questionable allowable and ultimate strength numbers) have resulted in thickness that do not result in SF > 4 when using the basic Div-1 formula for vessel wall thickness. I got 2.0" thickness using Div-1 formulas for one of the vessel materials above but the (Ultimate stress)/(Wall stress) is less than 4. Do I have to increase wall thickness to get > 4 SF? Maybe with the correct strengths my calculations will be ok.?
5 - Relative to potential future stamp: can I simply collect the material specification on each part as I proceed? Is the correct document the MTR? Any guidance here?
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