How to build a 50k ton forging press • Hacker News Board

Re: How to build a 50k ton forging press

#141

Post by shiroiushi » Thu, Aug 22, 2024, 7:15 AM UTC

bluGill wrote: post #72

shepherdjerred wrote: post #45

What strikes me is how great of an investment this turned out to be. Does the US invest in manufacturing like this anymore? Tangentially, if there were a war today would the US be able to produce as much as it did in WW2?

> Does the US invest in manufacturing like this anymore? No, but that is different from not investing. Today the US invests more in automation and engineering and less in manual labor. > if there were a war today would the US be able to produce as much as it did in WW2? It took several years to ramp up to WW2 level production. We would see the same, a couple years of trouble on the fronts while building industry at h…

I wonder how history would be different if Hitler had told France and UK to f** off with the WWI reparations stuff, threatening a war if they tried military action to force payment, but then didn't invade anyone and concentrated on developing their economy and becoming a technological and manufacturing power.

Re: How to build a 50k ton forging press

#142

Post by Animats » Thu, Aug 22, 2024, 8:03 AM UTC

azalemeth wrote: post #100

If you're reading this article, you may wish to know that arguably a "counterpart" to heavy press forging is explosive forming [1] in which a chemical high explosive is used to force a template material against a template. The overpressure generated by the explosive can be equivalent or maybe even greater than heavy press forgings (a 50,000 US short ton force press exerts ≈500 MN force; peak overpressure close to det…

Explosive forming has been used to make aluminum boat hulls.[1] It's a useful way to form very large sheet metal parts.

[1] https://www.youtube.com/watch?v=CbS6rS0seuk

Re: How to build a 50k ton forging press

#143

Post by pjc50 » Thu, Aug 22, 2024, 9:26 AM UTC

nickdothutton wrote: post #52

These massive presses are/were of strategic importance. Something politicians, most of whom seem to be lawyers these days, completely fail to grasp. I am not in general a fan of government subsidy, but I was very disappointed when the government of the UK declined to fund a large press in Sheffield, which would have been used to build the next generation of nuclear reactors. June 2010 timeframe. Luckily natural gas i…

We're not going to build the nuclear reactors either. The problem will finally be solved by re-permitting onshore wind and a lot of batteries imported from China.

(The "local supply chain is vulnerable to political uncertainty over long term project funding" problem is much worse in regard to trains, and has resulted in losing most of our train building capacity. See HS2 fiasco.)

Re: How to build a 50k ton forging press

#144

Post by wizardforhire » Thu, Aug 22, 2024, 9:40 AM UTC

kragen wrote: post #124

wizardforhire wrote: post #111

Earlier quoted context omitted.

This is exactly what dyneema is only with hdpe.

no, dyneema is not hdpe; it's uhmwpe, and it isn't just strain-hardened, it's gelspun

I stand corrected! Thanks for the headsup <3s

Re: How to build a 50k ton forging press

#145

Post by pfdietz » Thu, Aug 22, 2024, 10:54 AM UTC

hwillis wrote: post #119

pfdietz wrote: post #33

Earlier quoted context omitted.

I wonder if it's possible to do additive manufacturing with pre-elongated snippets of wire.

annealing, which resets the grain structure, happens at a lower temperature than melting or sintering.

Doesn't annealing take hours, particularly at the lower range of temperatures? Perhaps the additive process can keep the metal hot for a much shorter time. Granted, this also means stresses from the manufacturing process will not be removed.

Re: How to build a 50k ton forging press

#146

Post by pfdietz » Thu, Aug 22, 2024, 11:33 AM UTC

PaulHoule wrote: post #18

Nobody in North America has a press that can make a vessel for a nuclear reactor without making it in pieces and welding them together (probably adding a year to the schedule if you don’t use a new welding technique just developed in the UK not to mention people being anxious over the welds) There is a Canadian company that is gearing up to make small reactor vessels like the BWRX-300 but so far I haven’t seen a sign…

That is, a vessel for a pressurized water reactor. A reactor operating at lower pressure (like one using molten salt as a coolant) wouldn't need such a vessel, as the salt would not become highly pressurized, even in accident conditions.

I saw a link from some government minister in Canada named Don Morgan who stated a BWRX-300 would cost $5B (CAN), which comes to about $3.6B (US). $12/W (US) is not the worst, but it isn't great. Not clear if that was all-in cost or just overnight cost.

https://www.deassociation.ca/newsfeed/4-provinces-push-ahead...

Re: How to build a 50k ton forging press

#147

Post by refurb » Thu, Aug 22, 2024, 11:35 AM UTC

advisedwang wrote: post #77

This should be a lesson for free-market advocates, especially those who see the US economic boom as a result of laissez-faire economics. In reality there are opportunities the free market doesn't take, and wise government intervention can yield enormous benefit to the public.

Do you feel that the free market wouldn't have adopted it at some future point in time?

Re: How to build a 50k ton forging press

#148

Post by azalemeth » Thu, Aug 22, 2024, 11:48 AM UTC

abe_m wrote: post #110

hwillis wrote: post #20

> Forgings have the added advantage of variable grain direction which generally can be tailored to the stress patterns of a specific design. This is a super underappreciated fact! It's often repeated that forging is just stronger, but just squishing steel does NOT make it stronger. Forging a part is so much more than just smashing it into a shape. Steel cable is made of pretty ordinary steel which is stretched 100s o…

I'd really like to see some backing of these claims. I've seen "grain flow" claiming big gains for years in various enthusiast magazines (bike, motorcycles, cars, etc) as to why components are forged. Then I started working in engineering, and I can't find any support for these claims. For sure when a steel bar is worked down to become wire for a steel rope, it cannot be pulled to an elongation of 100x increasing str…

The best evidence for grain flow on a really atomic scale comes from what is called texture analysis in X-ray or electron-beam crystallography (or related techniques): you get a deviation in the distribution of Bragg peaks due to the fact that you have a non uniform distribution over the orientation of the unit cells within the crystallites in the bulk material. You can fit this in a spherical harmonic basis and quite accurately work out the excess or defect of the distribution, typically quantified in units of 'multiple of a random distribution' or mrd, again either in crystallographic axes or traditionally in three orthonormal axes – parallel to the surface of the workpiece ("rolling direction"), axially transverse to it, and normal to it. The phrase to search for is 'pole plot'. They're rotationally symmetric and an inverse projection over all space, and so usually only a quarter of a hemisphere is shown.

A very good example of the affect of annealing tungsten wire is here [1] – note that (a) there is a very clear orientation dependence that some difficult geometric transformations will undoubtedly show means that they are aligned in the wire drawing dimension; and (b) after annealing at 1600 ºC for an hour the preference is slightly reduced but still about 15 sigma away from random...

[1] https://www.researchgate.net/figure/001-110-and-111-pole-fig...

Re: How to build a 50k ton forging press

#149

Post by eternauta3k » Thu, Aug 22, 2024, 11:52 AM UTC

advisedwang wrote: post #77

This should be a lesson for free-market advocates, especially those who see the US economic boom as a result of laissez-faire economics. In reality there are opportunities the free market doesn't take, and wise government intervention can yield enormous benefit to the public.

You may be right, but your conclusion doesn't follow from the article.

Re: How to build a 50k ton forging press

#150

Post by eternauta3k » Thu, Aug 22, 2024, 12:02 PM UTC

hedgehog wrote: post #15

hwillis wrote: post #12

Earlier quoted context omitted.

> like cast iron doesn’t have fantastic high-performance material qualities Cast iron is a material, not a process. It's an unfortunate legacy term for very high carbon steel (>2% by weight, or The >1% carbon precipitates out into graphite within the steel, causing it to behave totally differently. Less rusting, but weaker and much more brittle when solid. Less viscous when liquid, so you can cast long and thin parts…

Monocrystalline turbine blades are one of those things that make me appreciate how deep the state of the art is for a lot of "simple" things when you look closely.

There's nothing simple about jet engines :)