Cement, powdered hydraulic inorganic cementitious material, after adding water and stirring into a slurry, can be hardened in air or better hardened in water, and can firmly cement sand, stone and other materials together.

There are six categories of general civil construction cement, namely Portland cement, ordinary Portland cement, slag Portland cement, porosyl Portland cement, fly ash Portland cement and composite Portland cement.

It is made of limestone and clay as the main raw materials, which are crushed, batched and ground to make raw meal, and then fed into the cement kiln to calcine the mature material, and then the clinker is added to the appropriate amount of gypsum and ground finely.

"How? Old Song, can you fix it? Although he generally knew that it was not difficult, Liu Hongjian was not an engineering student, and he did not know much about Daming's industrial capabilities, so he immediately asked.

Song Yingxing frowned with a few pages of paper with the cement production process, for this page full of typos, Song Yingxing didn't feel unreliable, and even regarded it as a book from heaven.

After all, the entire industry of the Xishan Workshop is all from the typo book provided by Liu Hongji.

"The limestone is there, not to mention the clay, as for this cement cellar, the old man still has to study it!" Song Yingxing didn't know how big the effect of this cement was, which made his big stall so excited.

But he is a rigorous person, and he naturally refuses to pack a ticket for something he has never done, but although he doesn't know the purpose of this cement, the development of the strange thing called the steam engine has been frustrated.

Anyway, being idle is idle, so it's better to help adults develop this cement first.

The two discussed and agreed to choose to produce slag Portland cement, which is only piled up on two hills from the slag of the Xishan Iron and Steel Workshop, which is easy to collect in China.

After making up their minds, Liu Hongjian and the two of them said they would do it, and there were many poor craftsmen who came to Xishan Workshop.

Carpenters, stonemasons, and blacksmiths were all available, and there were many people who could do their work, and in three days a small experimental cement cellar had been piled up on a large construction site on the right side of the main gate of the armory.

In the past three days, for the sake of this cement, Liu Hongjian has not even returned home, and the ordnance has Liu Hong's separate luxury private room, and he and Song Yingxing supervised the construction of cement cellars during the day, pondering the proportion of various ingredients, and grinding methods.

In the evening, the two of them ate without leaving the cement, and Song Yingxing felt that his adult was enchanted, and wondered if he should report to the saint to find a few imperial doctors to take a look.

On this day, according to the drawings, the cement cellar was finally completed, and next to the cement cellar, the powdered limestone clay mixture that was ground by the workers was piled up, and the mixed materials (coal stone, iron ore slag, etc.) and gypsum powder on the other side were also the big pile.

Under an order, several people sent the mixture into the cement cellar with a shovel, lit it and burned it for half an hour, poured it out and mixed it with the mixed gypsum powder again, and then loaded it into the cement cellar for calcination.

It was another half an hour, and when Song Yingxing gave the order to start the cellar, Liu Hongji's eyes changed.

This thing can not only be used to build dam mouths and buildings with steel bars, but it is all silver!

A worker opened the outlet of the cement cellar from the bottom of the side of the cement cellar, and a 'cement' flowed out of it.

This cement is black in color and emits unpleasant black smoke, where there is half a point of cement.

"I'm going to be O's, what is this? Why is it so dark? The expected cement was not seen, and Liu Hong's eyes gradually turned green.

"Don't worry, adult, it may be that there are too many coal and stones, and let the old man mix it again." Song Yingxing is not in a hurry, what is needed to develop a new thing is patience, and it is impossible for impatient scientific researchers to become experts.

That's right, I blamed myself for being too anxious, Liu Hong gradually saw that Song Yingxing was so calm, but he was not so sincere.

How can you succeed once, what is the love that invented the light bulb, people have failed more than 6,000 times, failure is success damn it, this is where it goes.

There is still a manual for this, if your eyes are black, you don't know how to tinker until the Year of the Monkey.

The two stabilized their minds and began to continue experimenting.

More than an hour later, the second furnace of cement came out of the cellar.

"The calcination is too light, and it looks like we have to do it all over again." Song Yingxing grabbed a handful of cooled products and sniffed them.

After another hour or so, the third furnace came out of the cellar.

"It's too tightly sealed, no."

……

He was busy until dark, and still failed to burn qualified cement, Liu Hong gradually went from the initial elation to the afternoon, and simply ordered someone to move a Taishi chair.

Lying down on the chair, he shook around and watched Uncle Song work alone inside and out.

"Well, preheating decomposition is a problem, and the other is airtightness." It was already completely dark, and Song Yingxing was still frowning.

"Get Song Lao, let's fight again tomorrow! Let's go back and have a drink. After a whole day of hard work, Liu Honggradually also knew that the invention of any new thing was not so easy, but not so urgent.

Early in the morning of the second day, Liu Hong yawned and stretched his waist as soon as he went out, when he saw that Song Yingxing had begun to direct the workers to fight against the cement again.

This Uncle Song is worthy of being a science and engineering boss, with this focus and patience, he left ten streets of experts in later generations, Liu Hong gradually said in his heart.

"My lord is up, look, this furnace seems to be working well." Song Yingxing saw Liu Hong gradually coming out, and immediately asked the workers to carry water and mud to start the experiment, and finally a smile appeared on his face.

This is already the eighth furnace, there is a table next to the cellar, pens, ink, paper and inkstones are readily available, every time there is a failure, Song Yingxing will sketch and summarize the reasons for the failure, and in more than a day, a basket of waste paper is thrown.

A few workers finished the cement, moved a few bricks, and put cement on them, like a wall, put several bricks together, and mixed a lot of gravel in the cement, and just hung on the ground.

The next thing is to quietly wait for the cement to dry naturally, Liu Hong's heart has already stopped, anyway, if he fails, it's a big deal to start over.

At this time, it was Song Yingxing who was nervous, because according to his estimate, this furnace was the most promising to succeed.

In order to dry the cement as quickly as possible, several carpenters simply set up a small fire next to the turn, more than an hour later.

"The head of the second gear, the prince, it's done! Look! One of the people shouted, and the other lifted the bricks.

The two of them only carried the upper part of the brick layer, but even the entire brick layer was lifted, and if it was an ordinary lime wall, it was absolutely impossible to bring up so many bricks in a row.

"It's done? It worked! Liu Hongjian couldn't believe it.

"Yes, my lord, this thing is so solid, and it can have such a great bond." Song Yingxing smiled slightly, but he was not too excited.

There are so many things he has developed, and this cement is just one of them, and when he gets older, there is so much excitement.

"Cement will definitely benefit the Ming Dynasty, Song Lao, this time you have made a great contribution again!" Liu Hong gradually kicked on the concrete, but he didn't shake it for half a minute, and checked the adhesion of the bricks, and then said happily.

"This is all the credit of the adults, if there are no drawings, where can the old man make such a thing, the old man is admired!" Song Yingxing is as modest as ever.

"Hahaha!" The two looked at each other and laughed.

This situation has occurred several times, Liu Hong gradually came out with drawings, Song Yingxing according to the drawings, and the two are also very happy to cooperate.

"You, you, you, and you, go find an ox cart and follow this king to pull the bricks into the palace to face the saint!" Liu Hong gradually ordered a few people to give orders.