Next, the formed castings are sent to the annealing kiln.

The annealing kiln is a pit type, and the kiln wall is divided into two layers, inside and outside, and there is a gap between the two layers, just like the double-layer bottle wall of a thermos, which can play a role in heat preservation.

The casting can only be completed after several days of annealing in the annealing kiln to decompose the carbon iron into graphite and iron, and eliminate the cementite in the casting.

Pig iron is hard and brittle, and without such annealing, it is brittle, but if it is properly decarburized and annealed, it can make the casting tough.

Three kinds of cast iron can be obtained by annealing: white-core ductile cast iron, which has high hardness and strength; Black-hearted ductile iron, slightly worse strength, but impact resistance and good toughness; Ductile ductile iron, extremely high strength, comprehensive performance is close to modern steel.

China's blast furnace in BC can produce one ton of cast iron a day, and the annealing kiln can anneal 2,000 pieces of iron at a time, and the production efficiency is very high, the problem is that Luo Yi does not have so many iron tools at present, this is only an experimental casting.

This time, the number of iron tools cast was small, but the time and manpower were not reduced much.

Therefore, on the whole, the cost of these pieces of iron is not low, if it is not for the raw materials and no money, it can be said to be a loss.

However, Luo Yi believes that the cost cannot be calculated in this way.

Experienced and organized manpower is more valuable than anything else.

The first move had the highest failure rate, so instead of starting with iron ore, she started with cast iron remelting. The selection of manpower is mainly those slaves, because they are all single singles, if a few serfs or freedmen are pulled, maybe they will do a better job, but if there is a personal injury accident, not to mention that several families may be broken up, even rumors are enough for her to drink a pot.

Many things, knowing the Tao and actually doing it, are two different things.

There is a joke that is very clear, the teacher asks the students to put the plaster on their hands, and the result is that some are attached to the palm, some are attached to the back of the hand, some are attached to the finger, and some are attached to the wrist......

With a few illiterates, from the beginning of burning refractory bricks to the baking of ironware, all kinds of things that happened during this period made people cry and laugh, more bizarre than all kinds of dramas, if Luo Yi was not immersive and responsible for completing it, she would definitely be happy.

But she is in charge.

So her situation during this time can be described as burnt out.

Sometimes she silently felt in her heart that, with their nature of being willing to rob rather than work, the God of these Westerners must have driven them out of the Garden of Eden because they had obtained the fruit by cutting down the tree of wisdom—and now she had a deep sympathy for that God, and it would not be easy to rule over such a group of men......

However, it is better to be illiterate than illiterate.

They did not question the appearance and purpose of the blast furnace, nor did they resolutely refute the fallacy that iron would turn into liquid, and although they drew talismans, prayed and turned around to spit on the burning of coal, they did not say that it was impossible.

If someone like a priest is used to work, maybe it will be quicker to get started, and it is more likely that he will not work at all - Luo Yi has given up the idea of letting him be a helper, and he is thankful that he will not be mischievous and oppose.

Now Mr. Priest's main job is to fool those knights.

He was still so-so in doing this job - the reason why he said this was because Luo Yi felt that she hadn't been put on the pyre by them yet, and she couldn't tell the rest.

A few days later, the iron plough was completed.

The agriculture of Brad's territory, after nearly two thousand years of iron tools used by the people of this continent, finally entered the Iron Age.

Those who have not experienced all this firsthand will never know how difficult it is to do this.

Luo Yi didn't know how advanced this was.

By the nineteenth century, Russian farmers were still using wooden ploughs on a large scale, because the landlords believed that spending money on iron farming tools would only make the serfs lazy......