So today we're going to continue with continuous caster and continuous caster operation.

As I already mentioned last time that this is going to be probably one of the most critical

points going forward when it comes to green steels and the reason being that in a continuous caster

segregation of detrimental alloying elements essentially kills our entire process.

So if you

want to make steel more than steel we're going to have to have a continuous caster and the continuous

caster actually lives and dies on melting intervals.

So if you have something with a very

wide melting interval that's not really great for a continuous caster because the basic principle

we talked about already last time the basic principle is that you solidify a shell and then

you just keep moving that shell along while the rest of the inside solidifies and while we're

cooling the strand.

So essentially we need to get all of the heat of the solidification out of the

material and in order for the whole thing to not be a gigantic sized continuous caster we were

essentially bending the strand which puts boundary conditions in terms of mechanical properties on

the material at this high temperature.

So if you have things that cause low melting residual

melt then you can get hot cracking hot tearing.

So what can happen is that the strand breaks open

and yeah this is not fun.

It's essentially going to spill out a lot of a few tons of liquid steel

into your cast house which yeah you should absolutely not do.

We didn't talk too much about different types of continuous casters because actually before there

were horizontal continuous casters there were vertical continuous casters but not really in

any large scale commercial operation at least not outside of Eastern Europe or outside there was a

pact in the Soviet Union and in Eastern Europe they used to have vertical continuous casters for

quite a while because they couldn't produce the steel purity as needed for a horizontal continuous

caster but outside of that there was never really any operation of vertical continuous casters.

By the way if you're interested in that kind of metallurgy tomorrow we're going to have a

guest in a department colloquium Professor Springer.

He's a professor at

at Uni Duisburg Essen and he's a specialist in sustainable metallurgy so he does a lot of research

into how you can tweak compositions to allow for higher scrap percentages and so on.

So if this kind of stuff interests you the department seminar is always Tuesday at 4 pm

in the Ilchener Hörsel in the H14.

Okay and yeah but what we usually have is our regular continuous caster that we talked about

last time and the regular continuous caster is a pretty pretty large factory hall about half a

kilometer long that usually includes some roughing rolling and some finishing rolling.

Of course if you only do heavy plates you might not have a finishing rolling line only a

only roughing rolling line but this really depends on what you're trying to make.

A full hot rolling plant costs about a billion euros in these days probably a little bit more

than a billion euros just to give you an idea of the cost of these kinds of kinds of devices.

Now if you go thin slab caster CSP or cast strip then it might be a little bit cheaper but you

might not get away with all the different grades that you would like to make because

the amount of hot reduction that you are going to be able to produce is going to be limited.

And it's kind of funny because last week I had a meeting with

oh yeah NDAs I can't say who a large steel company that seems to be the first ones that

produce flat products at scale from electric arc furnaces and they're using a CSP process

in one of their Spanish plants and so it's going to be interesting because you might get our hands

on one of the first batches of material that they're making making with this it's going to