The Complete Case FOR Nuclear

[turbguy + 1,398]

6 hours ago, footeab@yahoo.com said:

Actually, no.  SS works just fine.  Not plain jane SS, but Hastelloy, so slightly more expensive, but much easier to work/weld actually than "plain jane" SS.  Several videos where Gordon, or one of his colleagues talks about this issue.  The original salt reactor guys went through the same process of finding correct alloys for long term corrsion and wear properties.  Had it done in the 70's. 

The T limit IS only true if you do not place insulation on the INSIDE of the piping with a lining and cooling on the outside.  Once this is done, then the Temperature limit is in effect ~1200C.  Then add it is always possible to add NG at this point for a combined cycle and boost Temps even higher.

Frankly, it is pathetic that current nuclear reactors do not have a NG boost to Thot for much higher efficiency.  True, complexity goes up, but so does efficiency, by a massive margin.  Try upwards of 50% increase so... Plenty of room for improvement even on ancient tech, just no one is willing to play the Regulatory game of the NRC bumbling fools political hacks and their pack of slavering anti science, anti progress NIMBY's who hate humanity supporters. 

1200 C?  You mean 2200 F?  I want to see any alloy that can handle that operating temperature at the stresses imposed, for say, several years of service, before creep life is completely exhausted.

Common stainless steels are typically about 50% or more iron. Hastlloys (and other high nickel alloys) are good alloys, but iron is in the FAR minority of chemical composition.  That's a LOT of nickel (and chrome, and moly).  As I said, FE is a "tramp" in the mix.

And oh, DMW problems...

CT's do handle high firing temperatures in excess of that, not only with similar superalloys, but also via single crystal blades, ceramic coatings, and most importantly, convoluted and exotic air cooling schemes internal to the hot parts.

As for getting any licensed nuc plant adding adding a nat gas topping cycle---forget it.  Just build some CT's instead.  Nuc plants have trouble enough handling saturated steam...

Edited March 2, 2021 by turbguy

[footeab@yahoo.com + 2,131]

6 hours ago, turbguy said:

1200 C?  You mean 2200 F?  I want to see any alloy that can handle that operating temperature at the stresses imposed, for say, several years of service, before creep life is completely exhausted.

Let me quote myself: "The T limit IS only true if you do not place insulation on the INSIDE of the piping with a lining and cooling on the outside. Can be done because in effect, we are talking LOW pressure, instead of high pressure, and we are talking high volume(just enough to pump the liquid salt around) Once this is done, then the Temperature limit is in effect ~1200C",

Now for the real deal: Salts actually have LESS friction than water and is naturally lubricating in the liquid phase  But... The question is and always is about salts, corrosion.  So eliminating oxygen or backfilling with nitrogen would seem to be the obvious go to here...

Putting insulation on the inside of piping is already done in some very RARE instances.  But as you point out, but seem to forget about all ceramics inside pressurized turbines, those turbine blades are under extreme stress and would still be under this scenario with needed cooling etc, but I was talking the NUCLEAR side, which is the limiting factor of efficiency in current nuclear reactors as their Temperature output is LOW due to cladding issues on their rods.  As for ceramics inside piping currently it is extremely rare as said insulation is VERY brittle generally speaking to take said temps, but if we are talking salt under low pressure, salt who naturally lubricates... well, VERY LARGE possibilities open up in the ceramics side of things when there is no stress they are under other than wear resistance. 

Now it does make the heat exchanger very difficult to make, but at least the possibility is there, and if you use CO2 instead of water... for the high pressure high temp 1st stage turbine and say water for the 2nd and 3rd stage like normal....

EDIT: A picture is worth a thousand words... and lots of angst. 😁

PS: :Nuc plants are using very low pressure/temp turbines... why their efficiency sucks.... can't handle saturated steam... common man, pull the other leg.

EDIT: As for 1200C... military gas turbine engines rated for 10,000 hours are higher than this.  Also remember if one goes to CO2, the blades become FAR smaller than water turbines for same amount of power = far cheaper to make and as you 100% point out, creep at those temps... is a gargantuan problem.  How long will it be before the single crystal ceramics used in the latest Military engines comes to a power plant near you.  They are already using ceramic blades in latest GE turbines and I am sure Siemens etc are as well.  We aren't talking that much of a jump in technology here.

PPS: Gordon McDowell and company to get past the Nuclear Regulatroy Commission is only talking 700C, not 1200C.  And that is to use normal Stainless Steels and just get one operating and data coming in. 

Edited March 2, 2021 by footeab@yahoo.com

[Dan Warnick + 6,100]

50 minutes ago, footeab@yahoo.com said:

Let me quote myself: "The T limit IS only true if you do not place insulation on the INSIDE of the piping with a lining and cooling on the outside. Can be done because in effect, we are talking LOW pressure, instead of high pressure, and we are talking high volume(just enough to pump the liquid salt around) Once this is done, then the Temperature limit is in effect ~1200C",

Now for the real deal: Salts actually have LESS friction than water and is naturally lubricating in the liquid phase  But... The question is and always is about salts, corrosion.  So eliminating oxygen or backfilling with nitrogen would seem to be the obvious go to here...

Putting insulation on the inside of piping is already done in some very RARE instances.  But as you point out, but seem to forget about all ceramics inside pressurized turbines, those turbine blades are under extreme stress and would still be under this scenario with needed cooling etc, but I was talking the NUCLEAR side, which is the limiting factor of efficiency in current nuclear reactors as their Temperature output is LOW due to cladding issues on their rods.  As for ceramics inside piping currently it is extremely rare as said insulation is VERY brittle generally speaking to take said temps, but if we are talking salt under low pressure, salt who naturally lubricates... well, VERY LARGE possibilities open up in the ceramics side of things when there is no stress they are under other than wear resistance. 

Now it does make the heat exchanger very difficult to make, but at least the possibility is there, and if you use CO2 instead of water... for the high pressure high temp 1st stage turbine and say water for the 2nd and 3rd stage like normal....

EDIT: A picture is worth a thousand words... and lots of angst. 😁

PS: :Nuc plants are using very low pressure/temp turbines... why their efficiency sucks.... can't handle saturated steam... common man, pull the other leg.

EDIT: As for 1200C... military gas turbine engines rated for 10,000 hours are higher than this.  Also remember if one goes to CO2, the blades become FAR smaller than water turbines for same amount of power = far cheaper to make and as you 100% point out, creep at those temps... is a gargantuan problem.  How long will it be before the single crystal ceramics used in the latest Military engines comes to a power plant near you.  They are already using ceramic blades in latest GE turbines and I am sure Siemens etc are as well.  We aren't talking that much of a jump in technology here.

PPS: Gordon McDowell and company to get past the Nuclear Regulatroy Commission is only talking 700C, not 1200C.  And that is to use normal Stainless Steels and just get one operating and data coming in. 

It would seem that 3D printing technology might be useful in building some of the exotic components you talk about?  As you mentioned, GE is doing 3D with all sorts of metals and, I think but am not sure, an integration of ceramics into 3D mould/printing.  Have these techs already been employed in this type of work?

[Sebastian Meana + 278]

7 hours ago, turbguy said:

1200 C?  You mean 2200 F?  I want to see any alloy that can handle that operating temperature at the stresses imposed, for say, several years of service, before creep life is completely exhausted.

Common stainless steels are typically about 50% or more iron. Hastlloys (and other high nickel alloys) are good alloys, but iron is in the FAR minority of chemical composition.  That's a LOT of nickel (and chrome, and moly).  As I said, FE is a "tramp" in the mix.

And oh, DMW problems...

CT's do handle high firing temperatures in excess of that, not only with similar superalloys, but also via single crystal blades, ceramic coatings, and most importantly, convoluted and exotic air cooling schemes internal to the hot parts.

As for getting any licensed nuc plant adding adding a nat gas topping cycle---forget it.  Just build some CT's instead.  Nuc plants have trouble enough handling saturated steam...

Fluoride salts corrosiveness depends on how pure they are when they are melted, if there's oxygen and or water contained in it it will get nasty as it will form acids and bases in the reactor while is at work, if you purify it to veery high degrees and don't surpass the 800°C benchmark is less corrosive than water, the fuel chemistry can be a problem tho.

1200°C is the benchmark for a far future VERY high temperature molten salt  reactor, you don't really need those kinds of temperatures to get high efficiencies if you have a very smart use of the steam (reheating, printed circuit heat exchangers, maybe coupling the turbine condensers to water treatment units), it can get there with a heavy use of refractary ceramics, Things like Zirconium/Titanium-CarboNitride mixed with Silicon Carbide or Carbonitride to form a glassy very corrosion resistant structure, but that is veeery expensive.


800°C is just fine, 760°C AUSC turbines should get gross efficiencies between 60% to 67%, 700°C salt outlet temperature is enough to allow you to use an out of the shelf 650°C USC steam turbine that has a 55% efficiency,



A way to solve some of the problems posed by the LFTR, is just using a MCFR, a molten chloride fast reactor, which is among the simplest reactor designs possible, is just a tank, with eatable Magnesium and Sodium salt, with Uranium and Plutonium chloride salt mixed in it, has neutron reflectors all around to use 15% rather than 50% enriched fuel, the chemistry of Chloride salts is much better understood and since they are less corrosive than fluoride salts you can use 760 Stainless steel alloy or 916L steel, or any Super-Austentenic stainless steel for the parts that touch the salt.


>IT has a negative void and temperature coefficient since your coolant is your fuel, and if it expands or boils it loses power very fast.
>A two-fluid, double-zone molten salt reactor can produce up to 75% more Plutonium-239 than it consumes or 58% more Uranium-233 than it uses
>With Uranium-233 you can fuel current LWR reactors and just forget about uranium mining and enrichment all together, at the same time U-233 is a much better fuel and it would make current reactors into "Iso-Breeders" that produce as much fuel as the consume.
>MCFRs can be extremely compact, with mindcrushing power densities, Just to put into perspective at 1100MWt/m3, a small MCFR core the size of a Football ball, would produce 4600MWt, as much power as the most powerful diesel locomotive in the world.
>Because the fuel is in the form of chloride salts, reprocessing it is much easier, you can use Argonne's pyroprocessing technique which is a fancy version of the electrowinning used in almost all mining operation but adapted to nuclear requirements
>There are some problems, like having to use a heat exchanger between the fuel salt and the blanket salt since at 1MEV neutrons 12% of the U-238 will fission rather than become Plutonium, and as such 6% of your power output will come from the fissioning of Uranium in the blanket salts 

 

[footeab@yahoo.com + 2,131]

1 hour ago, Dan Warnick said:

It would seem that 3D printing technology might be useful in building some of the exotic components you talk about?  As you mentioned, GE is doing 3D with all sorts of metals and, I think but am not sure, an integration of ceramics into 3D mould/printing.  Have these techs already been employed in this type of work?

Could. Pretty much almost everything is possible with 3d printing in giant vacuum chambers.   In the case of piping having ceramic insulation, it could be a powder with a ceramic coating where the 3d printer can enter the pipes and seal the gap. 

[Rob Plant + 2,616]

12 hours ago, footeab@yahoo.com said:

Actually, no.  SS works just fine.  Not plain jane SS, but Hastelloy, so slightly more expensive, but much easier to work/weld actually than "plain jane" SS.  Several videos where Gordon, or one of his colleagues talks about this issue.  The original salt reactor guys went through the same process of finding correct alloys for long term corrsion and wear properties.  Had it done in the 70's.

When you say Hastelloy is "slightly more expensive" you're actually going from approx $2.80/lb for 316 st.st to $17.50/lb so its 6.5 times the price!

Won't Nimonic 80a or Nimonic 90 do the trick? Nimonic 90 has a working temperature above 1600F and is $9.35/lb?? half the price of Hastelloy.

[Rob Plant + 2,616]

4 hours ago, Dan Warnick said:

It would seem that 3D printing technology might be useful in building some of the exotic components you talk about?  As you mentioned, GE is doing 3D with all sorts of metals and, I think but am not sure, an integration of ceramics into 3D mould/printing.  Have these techs already been employed in this type of work?

@Dan Warnick There are 3D printing machines that work in Inconel 718 already but this wont get up to the working temperature @turbguy was talking about.

https://www.protolabs.co.uk/about-us/press/inconel-launch/

To be honest 3D printing is currently not practical as it is far too slow and costly.

Most components in turbines that have high temperature and pressure environments ie power stations use Nimonic 80a and these components can quite easily be machined on conventional CNC's 

@turbguy in my opinion is totally correct in that you have to use exotic alloys to stand a chance of maintaining the integrity of the metal alloy.

[turbguy + 1,398]

12 hours ago, footeab@yahoo.com said:

Let me quote myself: "The T limit IS only true if you do not place insulation on the INSIDE of the piping with a lining and cooling on the outside. Can be done because in effect, we are talking LOW pressure, instead of high pressure, and we are talking high volume(just enough to pump the liquid salt around) Once this is done, then the Temperature limit is in effect ~1200C",

Now for the real deal: Salts actually have LESS friction than water and is naturally lubricating in the liquid phase  But... The question is and always is about salts, corrosion.  So eliminating oxygen or backfilling with nitrogen would seem to be the obvious go to here...

Putting insulation on the inside of piping is already done in some very RARE instances.  But as you point out, but seem to forget about all ceramics inside pressurized turbines, those turbine blades are under extreme stress and would still be under this scenario with needed cooling etc, but I was talking the NUCLEAR side, which is the limiting factor of efficiency in current nuclear reactors as their Temperature output is LOW due to cladding issues on their rods.  As for ceramics inside piping currently it is extremely rare as said insulation is VERY brittle generally speaking to take said temps, but if we are talking salt under low pressure, salt who naturally lubricates... well, VERY LARGE possibilities open up in the ceramics side of things when there is no stress they are under other than wear resistance. 

Now it does make the heat exchanger very difficult to make, but at least the possibility is there, and if you use CO2 instead of water... for the high pressure high temp 1st stage turbine and say water for the 2nd and 3rd stage like normal....

EDIT: A picture is worth a thousand words... and lots of angst. 😁

PS: :Nuc plants are using very low pressure/temp turbines... why their efficiency sucks.... can't handle saturated steam... common man, pull the other leg.

EDIT: As for 1200C... military gas turbine engines rated for 10,000 hours are higher than this.  Also remember if one goes to CO2, the blades become FAR smaller than water turbines for same amount of power = far cheaper to make and as you 100% point out, creep at those temps... is a gargantuan problem.  How long will it be before the single crystal ceramics used in the latest Military engines comes to a power plant near you.  They are already using ceramic blades in latest GE turbines and I am sure Siemens etc are as well.  We aren't talking that much of a jump in technology here.

PPS: Gordon McDowell and company to get past the Nuclear Regulatroy Commission is only talking 700C, not 1200C.  And that is to use normal Stainless Steels and just get one operating and data coming in. 

I can envision such applications that you mention.

I'm quite familiar with the Rankine cycle.  Nuc steam turbines are scaled up designs from the 1920's.  They use the humble steam conditions from that era, and still use some chrome-moly low alloys to retard water erosion from dealing with the effects of expanding saturated steam while extracting work. And STILL the stuff leaks out, wears sealing surfaces, damages blading and seals.  And then there’s what happens to elbows in large steam piping (FAC damage).  Yeah, handling slightly expanded (wet) steam is an issue.

The industry MUST  have component lifetimes somewhat longer than 10,000 hr military engines (how many hot section inspections are performed during that time?). That's just a little over a year of operation.  I know that single crystal superalloys (with thermal barrier coatings) are used in heavy duty CT's. (I left the industry just before they came along). Single crystal ceramics?  Have not heard of them.

Using a different working fluid (such as CO2) certainly has benefits.  If you are after greater fluid densities, how about mercury?  You can get REALLY compact rotating machinery with that stuff.  Done in the 1930’s.  Using a multiplicity of working fluids complicates the entire plant.  Complications are to be avoided.  They invariably impact reliability.

I am only familiar with ceramic-lined piping for coal ash and pulverized coal handing systems (nothing very demanding service, just an abrasive wear resistant coating).  I get to wonder what happens to the adherence of such coatings during differential thermal expansion cycles. Then there's the issue of bends/elbows/fittings/welds. I suspect you want the ceramic to stay put for a long time.  Perhaps you have other insulation methods in mind?   An example of a working heat exchanger might help me understand where you are coming from.

Anytime a commercial nuclear plant is constructed, VERY conservative material margins MUST be imposed.  There is WAY too much at risk when you store all that energy in such a tiny volume. 

Operators are still human. When you start into the “unknown”, risks inevitably rise.  It used to be that when a process alarm unexpectedly arose to the operator, the first guess was “a sensor must have failed”. Now, a more encompassing “questioning attitude” is prevalent. The investigation of past failures has solidified a highly entrenched safety culture in the industry; not only about the “now known”, but the “what could be new”?

If you insist on constructing a nuclear power house that is expected to last 40-60 years (involving several generations of management and operators) with reasonable maintenance, first research reactors, then small commercial reactors must be built and operated for almost that long, before you scale up.

After saying all of that, the ''black art" of metallurgy will stand in the way. There will be considerable research, finding, qualifying and applying REALLY expensive alloys and processes, that will, all the more likely, require frequent inspection, and component repair/replacement.

 

 

Edited March 2, 2021 by turbguy

[turbguy + 1,398]

7 hours ago, Rob Plant said:

When you say Hastelloy is "slightly more expensive" you're actually going from approx $2.80/lb for 316 st.st to $17.50/lb so its 6.5 times the price!

Won't Nimonic 80a or Nimonic 90 do the trick? Nimonic 90 has a working temperature above 1600F and is $9.35/lb?? half the price of Hastelloy.

There's a whole menagerie of commercial superalloys (and follow-on treatments) to select from out there.   It boggles my mind.  I just envision the material supplier salesman lobbying for his stuff over some other guy's stuff...

[footeab@yahoo.com + 2,131]

12 hours ago, Rob Plant said:

When you say Hastelloy is "slightly more expensive" you're actually going from approx $2.80/lb for 316 st.st to $17.50/lb so its 6.5 times the price!

Won't Nimonic 80a or Nimonic 90 do the trick? Nimonic 90 has a working temperature above 1600F and is $9.35/lb?? half the price of Hastelloy.

In my ultra, barely there, cup of coffee, brief stint in nuclear field we were not allowed the use of many materials due to NIckel/Chromum content as they irradiate fairly readily and turn into horrific toxins, though this seemed to be UTTERLY arbitrary and just more thickness was required.  That being said...

As for $$$/lb, that is purely a matter of batch quantity/size and for the amount of piping required for a nuclear reactor, that is an entire batch size by itself and you would special order the whole thing.  As for what alloys, well, see first paragraph, and $$$ see below.

The $$$/lb thing on the tiny commercial market for anything not a normal alloy is expensive because you are buying the scraps of batches that others who ordered the WHOLE batch did not use and then resold the scraps to commercial sites.  So, if you look at this from Joe Bob in basement trying to make this, you are 100% correct regarding cost. 

The material quantities in question are not the problem, look no further than 316L or many of the PH stainless steels, or Niomic, all of whom use far more EXPENSIVE Chromium, Vanadium, Tungsten by % composition than say Hastelloy. 

PS: Ever machined PH stainless steels?  Oh my, they are a dream to machine and a dream to HT.  Why they are not used more... I do not know.  Yea yea, can't go super cold, but only a couple of them.  The others?  Wonderful.  Far easier to work with than 4340 for instance and yet engineer after engineering spec keeps calling out 4340 and its derivatives 4130/40 etc.  Slightly more expensive but you easily make the $$$ back in the machining/HT cost. 

[footeab@yahoo.com + 2,131]

6 hours ago, turbguy said:

There's a whole menagerie of commercial superalloys (and follow-on treatments) to select from out there.   It boggles my mind.  I just envision the material supplier salesman lobbying for his stuff over some other guy's stuff...

Damn, am I supposed to click a trophy or a laugh? 

[footeab@yahoo.com + 2,131]

7 hours ago, turbguy said:

I can envision such applications that you mention.

I'm quite familiar with the Rankine cycle.  Nuc steam turbines are scaled up designs from the 1920's.  They use the humble steam conditions from that era, and still use some chrome-moly low alloys to retard water erosion from dealing with the effects of expanding saturated steam while extracting work. And STILL the stuff leaks out, wears sealing surfaces, damages blading and seals.  And then there’s what happens to elbows in large steam piping (FAC damage).  Yeah, handling slightly expanded (wet) steam is an issue.

The industry MUST  have component lifetimes somewhat longer than 10,000 hr military engines (how many hot section inspections are performed during that time?). That's just a little over a year of operation.  I know that single crystal superalloys (with thermal barrier coatings) are used in heavy duty CT's. (I left the industry just before they came along). Single crystal ceramics?  Have not heard of them.

Using a different working fluid (such as CO2) certainly has benefits.  If you are after greater fluid densities, how about mercury?  You can get REALLY compact rotating machinery with that stuff.  Done in the 1930’s.  Using a multiplicity of working fluids complicates the entire plant.  Complications are to be avoided.  They invariably impact reliability.

I am only familiar with ceramic-lined piping for coal ash and pulverized coal handing systems (nothing very demanding service, just an abrasive wear resistant coating).  I get to wonder what happens to the adherence of such coatings during differential thermal expansion cycles. Then there's the issue of bends/elbows/fittings/welds. I suspect you want the ceramic to stay put for a long time.  Perhaps you have other insulation methods in mind?   An example of a working heat exchanger might help me understand where you are coming from.

Anytime a commercial nuclear plant is constructed, VERY conservative material margins MUST be imposed.  There is WAY too much at risk when you store all that energy in such a tiny volume. 

Operators are still human. When you start into the “unknown”, risks inevitably rise.  It used to be that when a process alarm unexpectedly arose to the operator, the first guess was “a sensor must have failed”. Now, a more encompassing “questioning attitude” is prevalent. The investigation of past failures has solidified a highly entrenched safety culture in the industry; not only about the “now known”, but the “what could be new”?

If you insist on constructing a nuclear power house that is expected to last 40-60 years (involving several generations of management and operators) with reasonable maintenance, first research reactors, then small commercial reactors must be built and operated for almost that long, before you scale up.

After saying all of that, the ''black art" of metallurgy will stand in the way. There will be considerable research, finding, qualifying and applying REALLY expensive alloys and processes, that will, all the more likely, require frequent inspection, and component repair/replacement.

 

 

Uh, mercury, while its fluid is SUPER dense, what you care about is its GAS phase and here Mercury comes up way short as its thermal capacity stinks and its gas T phase barely happens higher than water so... Why use Mercury?

Now ScrCO2... how do you keep it inside?  You would almost have to make a permanently sealed pressure vessel with dual HTXGRs and the only outputs are controls and power... Good luck on that, though I see this as the future.  Someone will do it.   Technically you could make this in a factory and then ship the presealed assembly and maybe a single CO2 pressure charge port, but the foundation alignment problems on such a ciritical piece of machinery... guess you could shim after the ENTIRE pressure vessel is delivered with accelerometers built into the turbine bearings.  Gets back to turbine blade length of life...   😁  Ah the ever ending engineering circle

EDIT: Just typed in material.... I remember this, vaguely when conversing with guys at PNL who work closely with INL... Here is article new high temp alloy allowed for 950C.  https://www.world-nuclear-news.org/Articles/Alloy-qualified-for-use-in-high-temperature-reacto

Edited March 3, 2021 by footeab@yahoo.com

[Rob Plant + 2,616]

8 hours ago, footeab@yahoo.com said:

In my ultra, barely there, cup of coffee, brief stint in nuclear field we were not allowed the use of many materials due to NIckel/Chromum content as they irradiate fairly readily and turn into horrific toxins, though this seemed to be UTTERLY arbitrary and just more thickness was required.  That being said...

As for $$$/lb, that is purely a matter of batch quantity/size and for the amount of piping required for a nuclear reactor, that is an entire batch size by itself and you would special order the whole thing.  As for what alloys, well, see first paragraph, and $$$ see below.

The $$$/lb thing on the tiny commercial market for anything not a normal alloy is expensive because you are buying the scraps of batches that others who ordered the WHOLE batch did not use and then resold the scraps to commercial sites.  So, if you look at this from Joe Bob in basement trying to make this, you are 100% correct regarding cost. 

The material quantities in question are not the problem, look no further than 316L or many of the PH stainless steels, or Niomic, all of whom use far more EXPENSIVE Chromium, Vanadium, Tungsten by % composition than say Hastelloy. 

PS: Ever machined PH stainless steels?  Oh my, they are a dream to machine and a dream to HT.  Why they are not used more... I do not know.  Yea yea, can't go super cold, but only a couple of them.  The others?  Wonderful.  Far easier to work with than 4340 for instance and yet engineer after engineering spec keeps calling out 4340 and its derivatives 4130/40 etc.  Slightly more expensive but you easily make the $$$ back in the machining/HT cost. 

Yes we machine these on a daily basis and also exotics like Nimonic, Inconel, Waspalloy etc. if you order in the aged conditioned they are very hard and difficult to work with, but buy from the mill in the solution annealed condition and age harden afterwards, just need to carry out the mechanical testing requirements at a lab afterwards. I dont understand your comment on 4340 as this is just a very very common carbon steel that is very easy to machine and you certainly wont make the $$$ back on machining times compared to PH , ie 17/4PH stainless steel is more than double the cost of 4340, the applications of these materials is very different and not interchangeable.

$$$/lb depends on whether it is a popular grade with a particular mill and what the alloying elements are that make that grade. As I mentioned you try placing an order for any grade of Hatellloy at any mill in the world where it isnt 6-7 times the cost of 316/316L and near enough double that of Nimonic.

We buy in mill batch quantities direct from mills not scraps as you say. I can assure you Hastelloy is far more expensive than most of the exotics such as Nimonic , Inconel, Waspalloy or other chromium/Nickel steels. We supply turbine manufacturers such as GE/Alstom and Siemens and supply nuclear power stations and nuclear subs very little Hastelloy is used in these areas.

Regarding parts for a nuclear island or sometimes called primary core then these parts have to be machined with virgin tooling and thoroughly cleaned down machines and once the parts are finished they have to be "swabbed" and the swab sent off to be tested to show if there are any impurities that could cause the material to be compromised. A machinist wearing a rubber/plastic wrist band for example that came in contact with the part could induce that metallic part to crack and fail in a core environment over time.

[Rob Plant + 2,616]

14 hours ago, turbguy said:

There's a whole menagerie of commercial superalloys (and follow-on treatments) to select from out there.   It boggles my mind.  I just envision the material supplier salesman lobbying for his stuff over some other guy's stuff...

Yes you're right there are literally hundreds if not thousands of grades out there.

You are way off the mark regarding a salesman lobbying "his stuff" over someone else.

All of these grades exist for a reason and that is down to the integrity of the material when under load, pressure and heat. it then comes down to the relevant cost of these grades. Generally the more exotic the more nickel is involved and the greater the cost and the more difficult to machine, although these arent the only driver of cost.

For example the various grades of super duplex are mainly used in the oil and gas industry for subsea use due to their inherent mechanical properties. Those that maintain their mechanical integrity at high temperatures such as the CrNi grades like Nimonic/Inconel are therefore used in those areas such as turbines.

If there is bugger all load, pressure and heat then use mild steel park railings as its commercially the cheapest, if there is then an engineer will specify what grade and specification to work to in order that the material wont be compromised in the relevant application and the strength of the material remains as per the specification. For example 4340 has a recommended working temperature of -100 to +400 deg C you wouldn't want to be using that if it was going into an environment of 500 deg C as it would lose its integrity/strength and could cause a failure.

[Rob Plant + 2,616]

11 hours ago, footeab@yahoo.com said:

In my ultra, barely there, cup of coffee, brief stint in nuclear field we were not allowed the use of many materials due to NIckel/Chromum content as they irradiate fairly readily and turn into horrific toxins, though this seemed to be UTTERLY arbitrary and just more thickness was required.  That being said...

You do know Hastelloy C276 has 57% Nickel in it and 16% Chromium don't you?

[footeab@yahoo.com + 2,131]

1 hour ago, Rob Plant said:

You do know Hastelloy C276 has 57% Nickel in it and 16% Chromium don't you?

Yup, do not argue about the "reasoning" of the NRC... 🙄

One side of mouth says radiation corrosion HORRID!  Do not use!  The other side... use it anyways. 

PS: Hastelloy and its numerous alloy group is just a name just like Wastelloy etc and the other super nickel alloys / high Chromium stainless alloys are all about the same.  Saying one is essentially saying the other. Slight shades of difference between them in terms of temp/creep/stress with addition of radiation corrosion  thrown in + normal corrosion. 

[turbguy + 1,398]

3 hours ago, footeab@yahoo.com said:

Yup, do not argue about the "reasoning" of the NRC... 🙄

One side of mouth says radiation corrosion HORRID!  Do not use!  The other side... use it anyways. 

PS: Hastelloy and its numerous alloy group is just a name just like Wastelloy etc and the other super nickel alloys / high Chromium stainless alloys are all about the same.  Saying one is essentially saying the other. Slight shades of difference between them in terms of temp/creep/stress with addition of radiation corrosion  thrown in + normal corrosion. 

On 3/1/2021 at 10:25 PM, footeab@yahoo.com said:

 

I've always wondered if the KKK was somehow involved in developing Waspalloy...

Edited March 3, 2021 by turbguy

[Rob Plant + 2,616]

22 hours ago, footeab@yahoo.com said:

PS: Hastelloy and its numerous alloy group is just a name just like Wastelloy etc and the other super nickel alloys / high Chromium stainless alloys are all about the same.  Saying one is essentially saying the other. Slight shades of difference between them in terms of temp/creep/stress with addition of radiation corrosion  thrown in + normal corrosion. 

Nope this is rubbish frankly.

The different grades exist due to the need for them in different industries and applications not because some metallurgist thought it a good idea to come up with a new grade! if you tried to substitute one for another as you suggest then you would end up with numerous valves, turbines, power stations nuclear subs etc blowing up/failing around the globe and the subsequent deaths of many many people. The parts that are made from these are critical in nature these materials are NOT interchangeable.

Yes I am aware that they are trade names from the likes of Haynes, Inco Alloys etc.

[turbguy + 1,398]

2 hours ago, Rob Plant said:

Nope this is rubbish frankly.

The different grades exist due to the need for them in different industries and applications not because some metallurgist thought it a good idea to come up with a new grade! if you tried to substitute one for another as you suggest then you would end up with numerous valves, turbines, power stations nuclear subs etc blowing up/failing around the globe and the subsequent deaths of many many people. The parts that are made from these are critical in nature these materials are NOT interchangeable.

Yes I am aware that they are trade names from the likes of Haynes, Inco Alloys etc.

Yes there are some significant reasons why there are so may available superalloys. 

It just seems that they are similar to "witches brews"...."add an eye of newt, a pinch of dragon scales, stir only during full moon".

[footeab@yahoo.com + 2,131]

3 hours ago, Rob Plant said:

Nope this is rubbish frankly.

The different grades exist due to the need for them in different industries and applications not because some metallurgist thought it a good idea to come up with a new grade! if you tried to substitute one for another as you suggest then you would end up with numerous valves, turbines, power stations nuclear subs etc blowing up/failing around the globe and the subsequent deaths of many many people. The parts that are made from these are critical in nature these materials are NOT interchangeable.

Yes I am aware that they are trade names from the likes of Haynes, Inco Alloys etc.

There are so many because they have no clue what will work when searching for superior alloys, and create families of ~approximate compositions/properties.  In reality, the engineer knows that most of these super alloys are all about the same and it comes down to bitching as you are doing about minuscia %%%% points and pretending a difference of upwards of ~20% is the end of the world when in reality you use whatever machines easiest/cheapest as the material cost is negligible compared to the manufacutring process unless you are truly up against a rock and a hardplace and need longevity over manufacturing cost and just making something slightly thicker to compensate. 

So the engineer settles on ~good enough and most superalloys disappear and become expensive even though they technically exist.

Edited March 4, 2021 by footeab@yahoo.com

[Rob Plant + 2,616]

17 hours ago, footeab@yahoo.com said:

There are so many because they have no clue what will work when searching for superior alloys, and create families of ~approximate compositions/properties.  In reality, the engineer knows that most of these super alloys are all about the same and it comes down to bitching as you are doing about minuscia %%%% points and pretending a difference of upwards of ~20% is the end of the world when in reality you use whatever machines easiest/cheapest as the material cost is negligible compared to the manufacutring process unless you are truly up against a rock and a hardplace and need longevity over manufacturing cost and just making something slightly thicker to compensate. 

So the engineer settles on ~good enough and most superalloys disappear and become expensive even though they technically exist.

I'm not "bitching" I'm pointing out that you are assuming all engineers dont know what materials to spec. and to use your words "have no clue" which suggests they are very poor engineers.

The only point I agree with on this post is about cost. This was the start of our discussion/disagreement when you were lauding using hastelloy which you claimed was "slightly" more expensive and I subsequently pointed out it is 6-7 times more expensive and double that of nimonic so why on earth would you use that? I asked you to point me in the direction of any mill in the world where this isnt so and I didnt get a response so I'm presuming you now agree with me. Machining times and tooling costs are a miniscule % cost in comparison with the material cost itself so your point on this is moot.

Anyway this discussion is going nowhere so i'm done

[Dan Clemmensen + 1,011]

I was an ardent supporter of nuclear power from when I was in high school (Oak Ridge High School, class of '67), for all the reasons stated at the opening post of this thread. I will add that the costs of installed nuclear plants are insanely high due to gross over-engineering to allay the public's irrational fears.

Then Fukushima happened. That was a once in 10,000 year event. That made me realize that if we have 1000 nuclear plants, we will see a once in 10,000 year event about once per decade. Even though each such event is really quite benign in real terms, the public will freak out. I do not think we can educate the public enough to overcome Hiroshima and Nagasaki. The problem is deeply ingrained and deeply irrational. Any rational analysis would show that the negative health effects of nuclear power are far, far smaller than those of fossil fuels and would remain so even if we relaxed the safeguards and even including a once-per-decade accident,  but there is no way to get this information past the fear.

If wind and solar were not viable, I would still be advocating the use of nuclear power as the only way to avoid climate change, and I would still be fighting that desperate but losing battle. But now, I have given up on fission power, and I hope we can implement wind and solar quickly enough to avoid a climate catastrophe.

[ronwagn + 6,290]

On 11/1/2020 at 10:12 AM, Boat said:

Go off on me all you want, I am used to made up narratives. Here is mine. Health care in particular has taken on huge costs from the FF industry. The Republican talking point on capitalism is let that market work. Do not pick winners and losers. Of course that is all crap while hundreds of billions were spent on damaged humans, much of it by governments and corporations making products. 
So why the conveluted process of whitewashing the true costs of FF instead of directly charging the source? 
Could it be big oil bought off Republicans decades ago? Isn’t this the real deep state today’s Republicans run? 
Why not all energy pay their true costs and let the market decide. Me thinks socialized FF would have a rough time.

First there was wood and a small population. People advanced civilization. Then there was peat and coal and whale oil. Civilization advanced further. Then there was oil and natural gas and and gasoline. Civilization andvanced. Then there was nuclear and it became uneconomic and left waste all over the world that was highly radioactive. It rarely ever cleaned up after itself and did not live up to expectations. Then there were wind turbines and solar panels and they are still competing with oil and natural gas and gasoline with the help of subsidies. Nuclear plants can no longer be economically built in America and are unpopular due to their many long term problems.  The fossil fuels are still the largest parts of the energy mix and it looks like they will continue to be for at least the next decade or two or three. 

Problems With Nuclear Plants and Radioactive Waste

https://docs.google.com/document/d/1Jp7yumkT6T1tEAdC4jb1K6LvO45rtoHwFbRcl08rrS4/edit

[Sebastian Meana + 278]

On 3/6/2021 at 2:58 AM, ronwagn said:

First there was wood and a small population. People advanced civilization. Then there was peat and coal and whale oil. Civilization advanced further. Then there was oil and natural gas and and gasoline. Civilization andvanced. Then there was nuclear and it became uneconomic and left waste all over the world that was highly radioactive. It rarely ever cleaned up after itself and did not live up to expectations. Then there were wind turbines and solar panels and they are still competing with oil and natural gas and gasoline with the help of subsidies. Nuclear plants can no longer be economically built in America and are unpopular due to their many long term problems.  The fossil fuels are still the largest parts of the energy mix and it looks like they will continue to be for at least the next decade or two or three. 

Problems With Nuclear Plants and Radioactive Waste

https://docs.google.com/document/d/1Jp7yumkT6T1tEAdC4jb1K6LvO45rtoHwFbRcl08rrS4/edit

Between "Cant" and "isn't because political incompetence" there's a difference, "can't" implies that there's something inherent to nuclear tech that makes it expensive, which is kinda bullshit, buying the materials for a 1.2GW nuclear powerplant is at worst 450 Million U$D, ad 800 million U$D in labour construction, and the profit and taxes the builder has to pay if is a turnkey project, boom you can make a reactor that last for 100 years for 1500U$D/KWe, other costs than that are management, political intrusion, and financing (interests compound over time)

You know why nuclear is expensive? Having to pay the NRC (which by the way is directed by antinuclear people since 2008 in the USA) to label something with "nuclear grade" after years of irradiation testing, like for example Flextape, a big roll of Nuclear grade flextape is 70U$D, while a roll of normal flextape is 5U$D, Nuclear grade flextape isn't in any practical or technical sense superior to normal flextape, just that has been tested years in irradiation chambers and has the nuclear label on it, the same it goes with every single of the miles of cable and pipework in a nuclear powerplant, including the concrete

As it turns out Japan, Russia, China, and South korea made the incredible discovery that if you make stainless steel pumps with the same alloys but without the "nuclear label on it", it works just as good as a normal "nuclear grade pump"
People is scared of nuclear stuff and radiation because most of them don't comprehend it, The jump from Wood to coal to oil to gas is from 16MJ to 30MJ to 45MJ to 55MJ, the jump from Natural Gas to Nuclear is from 55MJ to 80,000,000MJ, 1.5 MIllion times the energy density,

Also the nuclear waste is possibly the best part of it, because there's so little of it, a nuclear reactor with a output of 1350MWe will barely use 1250Kg of fissile material, and you know what? theres some valuable stuff on it, like Palladium, Rhodium, Ruthenium, Technetium, which isn't being done, in part because it is prohibited to do reprocessing in the US, or pyroprocessing, spent nucle|aer fuel should be reclasified as just "slightly used nuclear fuel" , because is what it is.

So when i hear people talking about Plutonium as nuclear waste, is just like when people used to talk about oil in coal mines as waste, or gasoline from kerosene refining as waste, or natural gas from oil wells as waste, just because isn't being used doesn't mean isn't useful, DuPont or Dow would have cracked pyroprocessing years ago if it was allowed or incentivized, and the KG of Reprocessed U-233 or Pu-239 would cost 5000U$D/KG, altho more of the revenue of pyroprocessing would have come from separating Fission products, as palladium is more expensive than gold, Technetium greatly increases corrosion resistance in any steel, and is a tremendous catalyst, and Rhodium prices are high since is so useful and there's so little of it

Edited March 7, 2021 by Sebastian Meana

[Strangelovesurfing + 737]

On 10/23/2020 at 8:46 AM, Marcin2 said:

The solution could be to build a cluster of nuclear reactors ( 20-30 GW) far from inhabitated areas and transport the electricity to the load centers through UHV DC connectors (600-1,100 kV).

The only problems with such solution is:

1. the source of water for the power plants - artificial lake is needed, 2 the risk of terrorist attack ( this can be mitigated with proper spacing of the subgroups of 4-5 reactors).

Clustered reactors of the same type are much easier and cheaper to build and operate. Also the waste reprocessing plant could be near this site as well as storage for spent fuel.

From the rational point of view location of nuclear power plants ( the only clean source of the base load power) in secluded area does not have any sense, but modern society with their lack of basic education is not rational

Don’t next gen reactors operate without water?