I learned skills in a different world

(There is most professional knowledge, you can skip it if you don’t like it)

The blacksmithing process generally includes picking materials, burning materials, forging, shaping, steel casting, quenching, tempering, and polishing.

Among them, the main difference between pig iron, wrought iron and steel is the carbon content. Iron with a carbon content of more than 0.05% is called pig iron; iron with a carbon content of less than 0.05% is called wrought iron; carbon content of less than 2% And % of it is iron, called steel.

Steelmaking is about accurately controlling the carbon content in iron and removing some other impurities.

In this world, although steelmaking technology is not yet mature, there are already methods of steelmaking and steel frying. People have learned to improve the hardness and toughness of steel through repeated folding and hammering. These two forging technologies that improve the performance of steel are widely used in the world. It's pretty common here.

However, there are still certain shortcomings in the steel frying and steelmaking technologies. For example, the steel frying process is complex and difficult to master. Steelmaking is not only labor-intensive and time-consuming, but also contains many impurities.

In addition, ironmaking still uses charcoal as fuel. The heat is not high and the blasting equipment is poor. As a result, the furnace temperature is relatively low and cannot reach the melting temperature of iron. The ironmaking effect will be greatly reduced. Therefore, Shen Fangshi wanted to slightly improve the ironmaking process. iron conditions.

He knows a better iron-making technology, such as the steel-filling method. The steel-filling method has many advantages compared with the hundred-refining method or the stir-frying method.

First of all, the steel filling method is simpler to operate and easier to master. To obtain steel with different carbon contents, you only need to mix pig iron and wrought iron in a certain proportion and smelt them.

Secondly, as a carburizing agent, pig iron has a high temperature after melting, which accelerates carburization into wrought iron and shortens the smelting time. Wrought iron becomes steel due to the penetration of carbon, and pig iron can also become steel due to decarburization. , not only productivity increased, but steel production also increased.

In addition, at high temperatures, the carbon, silicon, manganese, etc. in the liquid pig iron will react with the oxide inclusions in the wrought iron to remove impurities, thereby improving the quality of the metal. 1

What Shen Fangshi wanted to use was the two improved steel filling methods.

One method is to first beat the wrought iron into a thin piece about an inch and a half long and as wide as a finger, then wrap the thin piece tightly and put the pig iron on top of the tightly tied wrought iron piece. Then cover it with a straw mat stained with mud, and apply mud under the wrought iron sheet. It is put into the furnace for blast smelting. When it reaches a certain temperature, the pig iron will melt first and infiltrate into the wrought iron. After the two fuse with each other, it is taken out and beaten, then melted and then beaten again, and this is repeated many times. This not only shortens the time for frying and smelting wrought iron, but also reduces costs. 2

In this way, the steelmaking furnace can still obtain oxygen from the air, melt the pig iron in a reducing atmosphere, and also allow most of the flame to be reflected into the furnace to increase the smelting temperature. When the wrought iron is cut into thin slices and then clamped and tied, the molten iron of the pig iron can be accurately inserted into the gaps between several wrought iron flakes, increasing the contact surface between the pig iron and the wrought iron, making it easier for the wrought iron to absorb the molten iron of the pig iron. The carbon penetrates evenly. 3

The other is the "cycad" smelting method. This method was used by smelters to make steel from the previous world to later generations.

Its specific process is simpler than the first one.

When making steel, first put the wrought iron material into the furnace for blast heating, and then put one end of the pig iron diagonally into the furnace mouth for heating. When the furnace temperature reaches about 1,300 degrees Celsius, one end of the pig iron in the furnace begins to melt and begins to drip molten iron. At this time, the pig iron block is clamped with pliers and moved left and right to pour the molten iron evenly onto the wrought iron.

At the same time, keep turning the wrought iron so that all parts of the wrought iron can absorb molten iron evenly. After two showers, the wrought iron is clamped to an anvil and hammered to remove impurities. This process is generally repeated twice. 4

In general, although the steel filling method may still have problems with impure steel, it is sufficient for the current stage.

It’s just that these two methods are better, but there is a difficulty, and that is the furnace temperature.

Nowadays, only charcoal is used as fuel. Without coal, the temperature is difficult to meet the requirements. Even if Shen Fangshi wants to improve, it is difficult to make a meal without rice.

Perhaps it could be improved from the blast box and high-temperature iron-making furnace, Shen Fangshi thought.

Immediately, he immediately found relevant information books from the bookshelf.

In addition to using the mechanical principles of cranks and levers to push the water exhaust air box for air blowing, Shen Fangshi wanted to use a double-action piston air box.

The box body of the double-action piston bellows is a wooden box, which is available in square and cylindrical shapes. The box is divided into two layers with a partition, and the upper layer is equipped with a piston. The lower floor is an air duct. There are two air inlets at both ends of the partition. There is an air inlet at each end of the box. There is a valve installed on the mouth. The valve can make the air flow in only one direction.

When using this kind of bellows, you only need to pull and push the pull rod on the bellows, and when the piston plate moves back and forth, the air can be pressed out, thus achieving continuous air blasting.

In this way, the fireworks in the furnace will burn more and more fiercely when blown by the wind.

During the sinking process, a double-acting piston bellows with a cylindrical box body was prepared. The cylindrical box can convert the internal radial pressure into tangential tension, thereby withstanding higher wind pressure.

The double-acting piston air box is composed of a box body, an air blocking plate, a push-pull rod, an air tongue and an air outlet nozzle.

It is best to use willow wood for making bellows, because willow wood is not only elastic and has good dimensional stability, but also has a fine wooden structure, soft texture, and is smooth after being planed, making the box strong and durable.

The tools rewarded by the system are also very easy to use. The inner wall of the bellows can be easily planed with a wood planer, and the inner wall is very smooth.

Moreover, Shen Fangshi had already learned the mortise and tenon structure before. The entire bellows did not need a single nail, but relied entirely on the combination of mortise and tenon and wooden wedges. 5

If the original tree trunk is processed as a whole, the box wall made in this way will have no seams, uniform stress, and higher pressure-bearing capacity. It can be driven by hydraulic power to blow air for a large smelting furnace.

This not only improves the blasting efficiency, but also frees up manpower.