Wind Turbines

[ajohn]

If UK buyers want stainless steel that goes rusty, or screws with soft heads, or suits made of processed cellulose, China will provide them.

Usually due to what an importer chooses to import.

Actually I have bought some stuff that came from china that uses stainless grades that do what would be expected. Yes they were more expensive than some other options.

 

[Justin Passing]

progress on wind for instance appears to be similar to ours

They're behind us on wind. Ahead on solar though, particularly embedded. They like their biofuel too

Their use of their own brown stuff may have ended yonks ago - pass.

Still open-mining and burning it A big % of their power still, last I looked.

A friends parents always used it as cheaper and it did produce plenty of heat. Maybe more was needed, pass.

Coke is as you say, mostly carbon, so higher calorific value per mass, but the oxygen needs to get in there to so particle size/porosity can be important, Like you use willow charcoal for gunpowder... Coal can have volatiles which burn easily but not as hot - a pro/con.

China has so much cheap coal, they "can't not use it", it suits their stage of development so well. 2050 is pretty ambitious. Hats off if they make it, but it'll still be too late for the planet.

 

[ajohn]

China has so much cheap coal, they "can't not use it", it suits their stage of development so well. 2050 is pretty ambitious. Hats off if they make it, but it'll still be too late for the planet.

Trouble is for the west is that they are a very managed economy. If their gov says do it gets done. It's showing up in products. Router first. Other things can be thrown in eg 5g, trains and even mobile phones. The phones worried Trump. His actions - many think they wont achieve anything as the USA is not the only leader in certain fields and China will probably catch up anyway.

I do know one fact about manufacture there. About 20 years ago. USA company chose to have something made there. Accurate work. The cost saving over made in the USA when all was totalled up including shipping tooling back to the USA was ~7%. The bloke that organised it thought the same as me. Spread the extra cost if made in the USA over the number of items the tooling will make and isn't much at all. Trouble is that the parts made will make less profit or have to cost more. This bloke organised it all as was instructed by his management, A rather senior person as well.

My recollection is zero coal by 2050. No comments about usage up to then. I suspect their nuke industry is building. A USA politician reckons they have spent more on greening than the rest of the world combined. I've seen similar elsewhere.

 

[Justin Passing]

Usually due to what an importer chooses to import.

Actually I have bought some stuff that came from china that uses stainless grades that do what would be expected. Yes they were more expensive than some other options.

Everyone's "value engineering". Stainless with some sulphur is cheaper. If it doesn't affect the apparent quaity of John's screw, it'll get used. Instead of making it all "very good" we've become better at producing a range from excellent to pretty crappy, and use the crappiest possible we can get away with - or not get caught for.
Often someone will measure one parameter, like John's screw pronounced as OK because of the hardness, say.

Fine example was tank tracks in WW2. Hadfield's steel had been used traditionally - fine grain, good for casting.. It was hard. Hadfields happenned to have Mn. They changed grade, using ordinary common carbon steel the same hardness and toughness. What could go wrong? All seemed fine.
They didn't realise Mn's benefit in increasing work hardenability (It reduces the stacking fault energy in austenite phase, and bainite transitions - I did that stuff as part of "Natural Sciences"..)
Tank tracks wore out. They tried higher carbon. Different troubles - brittle. They went back to Hadfields steel. They still wore out. What??! Then they realised that they had to use Mn steel AND drive the tanks on hard roads to harden the tracks. When they had been sent straight to N Africa, used only on sand, it didn't happen.
Then a bloke who'd worked out the best steel for railway lines (similar issues) said "I could have told you that".
We're still making the same mistakes.

 

[Justin Passing]

Trouble is for the west is that they are a very managed economy. If their gov says do it gets done. It's showing up in products. Router first. Other things can be thrown in eg 5g, trains and even mobile phones. The phones worried Trump. His actions - many think they wont achieve anything as the USA is not the only leader in certain fields and China will probably catch up anyway.

I do know one fact about manufacture there. About 20 years ago. USA company chose to have something made there. Accurate work. The cost saving over made in the USA when all was totalled up including shipping tooling back to the USA was ~7%. The bloke that organised it thought the same as me. Spread the extra cost if made in the USA over the number of items the tooling will make and isn't much at all. Trouble is that the parts made will make less profit or have to cost more. This bloke organised it all as was instructed by his management, A rather senior person as well.

My recollection is zero coal by 2050. No comments about usage up to then. I suspect their nuke industry is building. A USA politician reckons they have spent more on greening than the rest of the world combined. I've seen similar elsewhere.

That's a typical story.
One canny bloke was Donald Rumsfeld. You may remember his comment, iirc to a journalist, about the known unknowns and the unknown unknowns. Wise people make an allowance for the latter, you can never rely just on what you think you know.

 

[fillyboy]

Usually due to what an importer chooses to import.

Actually I have bought some stuff that came from china that uses stainless grades that do what would be expected. Yes they were more expensive than some other options.

I had a job this year cutting out and replacing the render beads on a house because the galvanised beads had badly rusted, only option was to cut out the old and re-render the corners. **** job but someone had to do it.
Started off buying the stainless beads from Jewsons but after seeing the price double I started getting cheaper ones from another source, till I noticed rust spots appearing on them when I'd left them outside in the rain. Then discovered they were magnetic which was a surprise as I always though SS didn't contain iron.
Turns out that SS can contain iron but also has to contain chromium, the chromium molecules surround the iron molecules and prevent rusting. The amount of chromium seems to be the critical factor and cheaper ones with lower chromium content will rust.
The Jewsons ones were not magnetic.

 

[JohnD]

Also needs nickel, which is an expensive material so often omitted on cheap stuff.

 

[ajohn]

like John's screw pronounced as OK

They should have a specified tensile stress rating and standards exist. Actually I an not sure stainless can match steels just from general material tendencies. I wanted the best for holding stuff down on my machine tools. There is a decent source not far away and asked for unbrako as the bloke was old enough to remember what I wanted - the best in that respect. Cost was way over the usual price of steel cap head screws.They are also high precision screws especially the threading. That for me means high precision taps as well. Rather hard to come by. They are made on the basis of resulting in a certain final fit with standard screws. That means that there sizes differ from what precision ones need. Still rather accurately made though.

I spent some time on a drawing board. Tooling. At the time specific brands of materials had to be used - not standards as things are these days. Brands did vary. Standards tend not to. Another forum, a clock restorer wondering why parts in rather expensive old clocks now had high wear parts that would last for ~100years. Nothing remotely like it using modern spec'd materials. There was a metallurgist around. Some discusion as both new what the clock man was using and he said modern should be fine. The clock man had found some ancient stuff and had started using that to avoid upsetting his customers. He sent a sample to the metallurgist who looked at it pretty thoroughly and was mystified. The only technical difference between the 2 appeared to be that the old stuff was made from puddled Swedish steel. Physical characteristic were different.

I wont bore you with detail but I came across a similar problem with optical glass. No problem long ago but great doubt that it could be duplicated now even with details of the ingredients, This sort of thing crops up because companies can have secrets that they don't want others to know. Sometimes these secrets do not get passed on or may even get forgotten.

 

[Deleted member 18243]

Why haven't all businesses moved to China?

Production of most things has moved to China, have you not noticed?

 

[denso13]

Production of most things has moved to China

That wasn't the question.

 

[ajohn]

The Jewsons ones were not magnetic.

There are a number of different grades of stainless for different uses. Some are more ductile - say to make saucepans on a press. It serves well but not as stainless as some other grades. Then comes what is in my view rubbish really where it may be used.

Take stainless springs - they will be slightly magnetic however they are still pretty stainless. Other grades would work harden and snap. Some wouldn't need the work hardening, they just wouldn't work.

 

[Justin Passing]

Also needs nickel, which is an expensive material so often omitted on cheap stuff.

Completely wrong, far more to it.

Turns out that SS can contain iron but also has to contain chromium, the chromium molecules surround the iron molecules and prevent rusting. The amount of chromium seems to be the critical factor and cheaper ones with lower chromium content will rust.

Also not right, it's the srface.

If you take iron and pile chromium into it, you have stainless steel. But there's about 6 groups of stainlesses.
I could give you a lecture on stainless steel, but it would be better 4u2 look it up. It's a bit complex.
Also it's a long time ago when I did it and memory tricks make it easy to misplace something into the wrong group.
Basically it's Cr that makes it stainless, Ni is added to make it heat-treatable, then there's carbon and other elements like Mo, V,W, etc

The Ni is only there to make it hardenable not to increase corrosion resistance, though that can happen, it depends. Some lower Ni alloys like 304 are more corrosion resistant than higher Ni, say; It's complex. Other elements can be used than Nickel, like Mn and N.

The magnetic thing can be misleading. Try your cutlery or your sink. Stainless, but very possibly magnetic, possibly not. Ferritic stainless steel is ferromagnetic, but they all are, at least a bit.
If It's 18-10-2 then it won't be, because it's austenitic. Ferritic/austenitic are names for phases, - atomic arrangements in the crystals in the metal.
It's the object surface which gets Cr203 on the surface to make the stuff stainless. Think of most of the alloying elements as in solid solution, like salt and alcohol in water, frozen. Yes they affect the corrodablity of the matrix, not the surface so much. There are several corrosion modes... grain boundaries are attacked by chlorides, or stress and air even.
Carbides are more like hard particles, partly, depending on concentration.

The magnetic thing is further complicated - there are several types of magneticness, like paramagnetic and others. Tiny amounts of surface ferrite can make something appear to be ferromagnetic.
Odd things occur - eg you can put a SS in a lathe chuck or a steel bin, and have it later show rust, because of "ferrite pick-up".

Also if you bend something it can become ferromagnetic, so how was the plaster bead made? Possibly not annealed or normalised or tempered - hard is good .

If you paid through the nose and had the best possible alloy hat exists for your plaster bead, none of those will happen, but it's just plaster bead, so,....

I'm expecting someone to talk about plastic plaster beads next. Don't rust so must be good, right? Nope"!

Ajohn's springs will have a lot of carbon in them , probably. You could get a similar result with Cr-Ni-MO-V - W alloys and less carbon.

Carbon-containing phases arrest stacking faults, which is the mechanism of bending, like a ripple on a carpet moves the carpet if you move the ripple. That's one wat of hardening. ANother is WORK, which pushes all the ripples to the grain boundaries, another is heat treatment, which modifies the distribution of precipitates, another is alloying in the solid solution which basically just makes it stiffer.

e & oe due to senility....

 

[Justin Passing]

They should have a specified tensile stress rating and standards exist. Actually I an not sure stainless can match steels just from general material tendencies. I wanted the best for holding stuff down on my machine tools. There is a decent source not far away and asked for unbrako as the bloke was old enough to remember what I wanted - the best in that respect. Cost was way over the usual price of steel cap head screws.They are also high precision screws especially the threading. That for me means high precision taps as well. Rather hard to come by. They are made on the basis of resulting in a certain final fit with standard screws. That means that there sizes differ from what precision ones need. Still rather accurately made though.

I spent some time on a drawing board. Tooling. At the time specific brands of materials had to be used - not standards as things are these days. Brands did vary. Standards tend not to. Another forum, a clock restorer wondering why parts in rather expensive old clocks now had high wear parts that would last for ~100years. Nothing remotely like it using modern spec'd materials. There was a metallurgist around. Some discusion as both new what the clock man was using and he said modern should be fine. The clock man had found some ancient stuff and had started using that to avoid upsetting his customers. He sent a sample to the metallurgist who looked at it pretty thoroughly and was mystified. The only technical difference between the 2 appeared to be that the old stuff was made from puddled Swedish steel. Physical characteristic were different.

I wont bore you with detail but I came across a similar problem with optical glass. No problem long ago but great doubt that it could be duplicated now even with details of the ingredients, This sort of thing crops up because companies can have secrets that they don't want others to know. Sometimes these secrets do not get passed on or may even get forgotten.

I recognise some of that too! Definitely some of the "old stuff" was better in some ways, which could be reproduced if someone analysed it, and could be bothered.
Some of those clock parts, they chucked in graphite to cool, which of course became carburised (case hardened) to an extent.. They knew all about work hardening, and did that to within an inch of the metal's integrity, but it sure lasted a long time in the right application.

It was routine to "burnish the pivots" of clock and watch wheels, which means sort of ironing them to a superb finish, which also work hardens them. That wouldn't happen now, so much..
Things got incorporated by accident sometimes. Steel was "blued" to look nice, which was heating in a salt, which of course imparted chemicals to the surface, especially to passivate it.

Puddled Swedish steel was remarkably fine grained, but I can't remember why. Lack of contaminants I think. There was one called "Hoop-L", similar. I have some files made from it, still working fine. Some of it predates Bessemer method. There are stories of old stocks being discovered, wrapped in no more tha brown paper but free from rust, behind later-made stock which is badly rusted. There are also people diving for pre WW1 navy ships to get "pre-radioactive" steel, which is a wierd one to look up.

If you have a squint at an iron-carbon phase diagram it's a complex one and that's just 2 elements, and you have to know about heat treatment to use it. Then add Cr and you have a ternary, then add another few elements, and it can become too complicated to predict exactly what you'll get.
"Duplex" stainless steel came out of very careful manipulation and a bit of luck - good stuff. Alloys like Hardox and Hardox Tuf come up as much by someone's intuition than prediction. They work.
Then add portions of Model T, Austin Ruby and Ford Cortina, Bronco.....

Glass - ah well, I still have some Zeiss lenses made from radioactive glass, which turns a warm yellow depending on UV exposure. And some Nikon exotica for UV photography. Glass technology with the lates t RI's and low dispersions weren't dreamt of a couple of decades ago.

 

[Deleted member 18243]

I brought you details of the con whereby wind farmers can charge you twice for the same power, well this piece gives the lie to the claim that "wind power costs nine times less than gas power".

The true cost of renewable energy

Having delivered his platitudes on climate change at Cop27, Rishi Sunak returns to a more pressing problem: how to keep Britain’s lights on this winter. Last week it was revealed that the government has been wargaming a ‘reasonable worst-case scenario’ in which blackouts last up to a week...

www.spectator.co.uk

 

[ajohn]

I brought you details

Interesting. We only have one pumped storage unit in the UK as far as I know. It's been around for some time. It needs a big hole in a small mountain. It purpose is taking up surges as it can react extremely quickly giving plenty of time to get a generator up and running if needed.

TV and kettles surges - it's good at handling that.

Many seem to accept that wind needs storage and that is costly. This is very probably why countries are leaning towards nuclear which can be arranged to produce variable outputs. Any excesses could also be used for hydrogen but liquificaton needs even more power. As some are now pointing out with LNG. It's done by cooling to rather low temperatures.