The welding technology in forging is to forge the workpiece, then heat the edges to soften them, and then use a hammer to smash the edges of the two iron pieces together.

The blacksmiths did not stop busy at night. They hammered the several halves of the pressure cooker together, and then connected them to the bottom of the pot. The body of the pressure cooker was completed.

The finished pot body looks very rough. The pot body is irregular, somewhat flat, with prominent welding marks and some rough burrs.

The craftsmen themselves couldn't bear to look at such an ugly ironware. They found it embarrassing, so they suggested that it be polished and repaired.

Li Mengxi said, "That's not necessary, right? It can be used without repairing it."

Blacksmiths also pursue beauty, but Li Mengxi does not pursue this. It does not matter whether it is ugly or not. What is important is that it must be strong and have good sealing.

During the water leakage test, the pot was filled with water. After inspection, there was no leakage anywhere and it was completely qualified.

Now that the pot is there, all that's left is the lid.

The difficulty of the pressure cooker is not in the pot, but in the high sealing between the lid and the pot.

As for the sealing method, Li Mengxi did not choose to use a complicated design. He chose a method similar to that of a kimchi jar. The rim of the pot is larger and the lid can tightly fasten the rim of the pot. Then he directly pours molten iron around it and seals it directly.

Damn, this kind of sealing effect is definitely better than a real pressure cooker. No matter how tight the pressure cooker is, there will be a small amount of air leakage, but if it is sealed with molten iron, there will be no gaps at all.

It didn't take the blacksmiths long to hammer out a pot lid. Like the pot body, the pot lid was also very thick, heavy, and heavy, as heavy as a shield.

When I put the forged lid on the pot, the problem suddenly appeared, the pot lid was too big.

The blacksmiths went back and changed it again, and then came back and tried again.

This time the size was right and the lid of the pot was round enough. However, because the pot was not made well, the pot was flat and the lid did not match the pot.

The craftsman in charge of making the pot lid checked the pot lid several times, but when it didn't match, the craftsman could only take the lid away in embarrassment.

As Li Mengxi expected, it is easy to make an iron pot alone, and it is also easy to hammer a pot lid alone. However, it is several times more difficult to make two matching things, the accuracy is not enough, and the error is too large.

In the end, the pot lid was changed again and again. The round pot lid was changed to a semicircular lid with one side high and one side low. Finally, the pot and the lid fit together.

There is still one last step left, which is to drill a small hole in the pot lid for pressure relief. Otherwise, the pressure of the air pressure can be extremely high. If a crudely made pressure cooker does not leave a vent hole and seal it completely, it may not be able to hold up.

After a while, the steam will blow up the pressure cooker, just like a bomb.

Li Mengxi looked at the pot again and again. He felt that the pot was not big enough, and he was afraid that the pressure relief hole was too big and the pressure would be released too much, resulting in insufficient pressure in the pot. So in order to obtain a higher pressure, Li Mengxi told the craftsman that only the pot lid

Punch a hole slightly larger than the needle. The smaller the hole, the better.

This requirement put the craftsmen in a difficult position, because the thinnest chisels they had were thicker than wheat straw. It was too difficult to drill a hole the size of a pinhole.

It was difficult to return, so the craftsmen did not say anything and went about their business.

Li Mengxi waited for a long time before the craftsmen brought over the finished pot lid. At this time, the night was getting deep.

Although the night was deep, Li Mengxi finally finished cooking the pressure cooker. He didn't want to go to bed immediately. He wanted to try the effect of the pressure cooker.

The pressure cooker was built to test papermaking technology. It is known that the plant fibers in the herbs are dispersed as much as possible, which is the core key to papermaking.

It is also known that there is a substance commonly found in herbs that locks fibers and interferes with papermaking.

A tip from Guan Yu. Guan Yu said it might be gum. This guess is very reasonable. There is a high probability that gum needs to be removed during the papermaking process.

Well, after the pressure cooker took two days to prepare, the first step to test is to find the gum, then add acid, alkali and salt and try it in turn to see which case the gum is decomposed most thoroughly.

Li Mengxi went to search for materials all night. He looked for glue but couldn't find it. Regardless of peach gum, tungsten gum or the like, in the snowy season, he couldn't find any glue.

Li Mengxi didn't want to give up. In desperation, he didn't use pure glue. He directly found raw hemp, and then ordered people to guillotine the raw hemp, cut it again, chop it again, and chop the hemp into pieces that could not be broken again.

.

The coolie who helped to chop the hemp was naturally Guan Yu. Guan Yu was very busy chopping, cutting and chopping the hemp. Li Mengxi was still standing by and said, if it is not broken enough, chop it again.

After Guan Yu chopped it several times, he finally couldn't bear it anymore and put down his axe. "This is broken enough. If you chop it any more, it will catch fire."

The hemp was so chopped that it almost caught fire. You can imagine how many times Guan Yu chopped it.

Li Mengxi had a vague impression of industrial papermaking. When papermaking factories made paper, they had large crushers that crushed the raw materials into fine powders that could be blown up by a gust of wind. The material particles were fine enough, and naturally, they were produced in modern papermaking factories.

The paper texture is very delicate.

Li Mengxi realized that raw material crushing was also a key link in papermaking.

It can be crushed by hand, whether it is chopped with a guillotine or chopped with an axe. No matter how hard you try, the raw material is still very rough, and it is still a knuckle-length piece of hemp, which is not comparable to the powdered grass powder.

Li Mengxi thought, how to make a pulverizer? In the late Han Dynasty, there could be a water exhaust box, and also a hydraulic pulverizer. If the hydraulic pulverizer is not easy to use, other crushing methods are grinding, stone mill, and stone mill to grind the raw materials.

, can also improve the quality of paper.

Li Mengxi jotted down his ideas. One was a [pulverizer for crushing raw materials used in papermaking], and the other was a step back substitute, [stone mill].

Li Mengxi asked Guan Yu, "General Guan, can the stone mill grind the twine, wheat straw, etc.?"

Guan Yu, who was holding a basket of broken flax and preparing to pack it, was suddenly startled, "...Wheat straw? What are you grinding wheat straw for? Can wheat straw be ground? This...I don't know."

This chapter is not finished yet, please click on the next page to continue reading the exciting content! Guan Yu can't answer.

Li Mengxi's question is too weird. If you don't grind good grain, who has nothing to do to grind wheat straw?

With the broken linen ready, the test officially began. Li Mengxi found a new piece of linen cloth and officially recorded the first round of testing——

【1 Boil hemp with vinegar to see if the gum can be removed, and cook the raw hemp into pulp. 】

There isn't a lot of vinegar in the army. It's usually used for cooking and seasoning. I use it sparingly every time and I can't bear to put in more.

Li Mengxi, who was in urgent need of vinegar on weekdays, was afraid that there would not be enough vinegar at this time, so he poured half the jar of vinegar into the iron pot.

When it is poured, the sour smell permeates the air, making the mouth water of the person who smells it is sour.

After pouring half a jar of vinegar, Li Mengxi took a lot of chopped sesame seeds and threw them into the pressure cooker, and then added water. After the water was 90% full, Li Mengxi put a lid on the pot, and Li Mengxi ordered the craftsmen to fetch the molten iron.

Several blacksmiths came in a hurry with pliers holding the red iron. Then the blacksmiths poured the iron along the lid and onto the edge of the pot. Then while the iron was still hot, they quickly used small hammers to jingle the iron.

smash.

Finally, the craftsmen used molten iron to seal the lid all around.

Li Mengxi circled around the pressure cooker and looked closely at it. (This way, it should be completely sealed.) He thought.

Seeing that it was really getting late, Li Mengxi looked at the blacksmiths who were busy late into the night and said, "Thank you, it's late at night. Come back and go to bed early."

After saying that, Li Mengxi thought for a moment and then said, "Leave one person behind. If the iron is not sealed properly and it needs to be repaired again, who will be left behind?"

The craftsmen did not push the envelope, but all wanted to stay.

All fools know that opportunities are rare, and you have to show your face when things happen.

In the end, Li Mengxi only chose the blacksmith who seemed to be the youngest to be able to carry it, and sent the others back to sleep.

This night is destined to be sleepless.

In the main hall of the city lord's palace, a pressure cooker was propped up on a stone, with firewood placed underneath and a large pile of firewood piled beside it. Guan Yu was lighting a fire with flints, and Li Mengxi came with his armor in his arms.

After Li Mengxi waited for the fire to be lit, he handed the armor to Guan Yu.

Guan Yu was confused.

"It's better to put on armor, I'm afraid it will explode." As he said that, Li Mengxi buckled on his iron helmet.

Guan Yu pointed at the pot in confusion, "Can this thing explode?"

"Maybe it will explode with a bang." Li Mengxi said seriously.

As soon as Guan Yu heard that the pot would explode with a bang, and that burning the pot was actually very dangerous, Guan Yu couldn't help but wave his hand and told Li Mengxi to stay away while he lit the fire.

Li Mengxi is also afraid of frying pots. Burns caused by high-temperature steam are no joke. If the pot explodes, the iron pieces will fly like a bomb, which is very dangerous.

Guan Yu did the work for him, while Li Mengxi stayed far away, waiting aside.

Guan Yu was very generous, guarding the pot calmly and slowly adding firewood from time to time.

After a while, when Li Mengxi was done cooking, he reminded, "General Guan, check to see if there is any air leakage from the edge of the pot."

Guan Yu then stood up to check.

I looked around the pot and found no leaks.

Guan Yu replied that he had not.

Li Mengxi nodded. It seemed that the sealing method using molten iron was very good.

Continue to wait, and after another period of time, the water in the pot may have boiled, and the steam began to come out along the vent hole.

It was late at night and it was very quiet, and the sound of steam sizzling was particularly obvious.

It was cold, and the water vapor in the pot shot up into a straight line of white steam, which was impressive. Guan Yu looked up with interest and watched the white steam transpiring.

Li Mengxi, who was far away, was also staring at the steaming water vapor.

The water must be boiling, and the pressure in the pot has reached a certain level, but isn't the water vapor excreting too fast? It's just a small hole the size of a pinhole, and the water vapor is rushing out.

How much pressure is released?

The original intention of drilling a small hole in the pot lid is to relieve pressure, but the pressure relief effect is too strong, right?

Li Mengxi couldn't help but think of a real pressure cooker. A real pressure cooker didn't seem to vent at all. There was a small valve on the pressure cooker. When the meal was done, the pressure cooker began to deflate. The purpose of deflating was also to allow safe lifting.

Just a pot.

Li Mengxi also thought that according to later generations of household pressure cookers, the pressure cooker could not release pressure during the entire cooking process. The pot was very thick and could withstand ultra-high pressure.
To be continued...