Fanning sat on a small stool in the cannon casting workshop, silently organizing tools. As a well-known master of bell casting, he has been working here for more than three years, at the age of 50.

In the past three years, he had more than ten cannons cast by him, and his experience was abundant, so he was on the rank of the third group and his staff were convinced.

As an old comrade, Fan Ning was rated as a fifth-level worker by the workshop manager, and his basic monthly salary was ten cents. But he was also the head of the team, so he had to add ten cents.

Then, including their group's performance salary and task rewards, Fanning can easily get thirty or fifty taels.

Compared with previous days, this is a super generous treatment.

Unfortunately, he was very smart and gave birth to a stupid son. His only son Fan He has been in the factory for two years, but he is still a second-level worker. His basic monthly salary is only four cents, and the maximum monthly salary is not more than ten cents.

So Fanning was not satisfied with his achievements at all, and he was still sincere and worked hard every day.

He hopes to save more money for his descendants before he retires. He hopes that he can go further and be qualified to send his grandson to a technical school run by the Ministry of Works.

As long as he sees his son, Fanning will know that he does not have the capital to "enjoy".

In addition to him, there are more than 20 people in the three groups. However, half of them are inexperienced rookies. They are students from technical schools or descendants selected from martyrs' families. Apart from being quite smart, they are clumsy in everything they do. Even at critical moments they can only cause trouble.

But even so, Fan Ning had to endure it. Because these people were the direct descendants of the court.

Fanning was packing up his tools and thinking about things in his mind.

A short distance will lead to a short distance.

Those people from technical schools have a lower level of skills, but they are all very polite, and they are not the empty candids. They can still put forward some incredible ideas for specific issues.

The target of the third group was not small cannons, but medium-sized cannons with ten kilograms of ammunition. In the plan of the Governor's Office of the Five Army, this size of cannon was already the main cannon on the warship.

It is also considered a heavy artillery in land warfare, and it is a powerful weapon for breaking enemies specifically against city fortresses.

Therefore, for this kind of artillery and the evolved 12-pound cannon, the requirements of the Five Army Governor's Office are not only powerful, but also durable and "precise". They cannot be too heavy, and they must have certain outdoor movement capabilities.

This is troublesome.

After years of casting and experience summary, everyone knows that if it wants to hit far and long, it must be heavy first.

Only when the thicker the barrel and the larger the diameter of the gun are, will it be more powerful. The thicker the gun wall and the heavier the volume, can it be more durable.

Therefore, the Qing Dynasty in history had those generals weighing 10,000 kilograms.

However, after such a heavy gun body is paired with the gun mount and ammunition box, the movement speed in land warfare is infinitely close to zero.

It is not that it is really heavy and can no longer move, but that it means that the defect of such a heavy cannon is too great in the face of an unpredictable battle situation on the battlefield.

So this is a very paradoxical thing.

Fortunately, the materials of the three groups of cast guns are not only cast iron, but also a large amount of bronze and brass.

The experimental results show that the copper cannon with the same power is much lighter and more durable than the cast iron cannon. However, the cost of the copper cannon is obviously much greater than that of the cast iron cannon.

At the same time, all the gun casting teams have the same issue - that is, how to reduce the scrap rate!

The mud mold casting gun is a technology that the casting gun team has been using since the beginning. It comes from the casting process of copper bells.

The working efficiency of this cannon casting method is not high. It takes a long time to repeatedly reverse the mold, while the molded mud mold takes a lot of time to dry the dust. It usually takes several months to cast a cannon.

This thing (mud mold) cannot be dried or baked. The mud mold made of clay is prone to drying and cracking when drying and baking. Once it is dried, the mud mold will be scrapped.

When casting a cannon, once the moisture in the mud mold does not completely dry out, the water vapor in the mud mold will precipitate when casting is pressed by the hot iron gas, and the casting cannon body will easily have honeycomb tissue such as pores, resulting in the complete failure of the cannon.

If you can cast a mud mold cannon, if you can successfully cast 10 doors, it is already a very high proportion.

Zhao Gou naturally heard of the iron mold casting cannon method. As Lao Bai at the starting point, the iron mold casting cannon method has appeared in many history books.

But he did not give any prompts to the Cast Artillery Bureau.

This method is like a Minni rifle, and will become a secret treasure for the Song Dynasty to suppress the country's destiny and be quietly passed on to future generations.

In today's era, the results of mud mold casting cannons are already invincible.

Zhao Gou doesn't need to simply upgrade the firearm.

That would only destroy Zhao Song's leading position.

Because the Minni rifle and iron mold casting cannon method do not have too high technical content, after the firearms spread all over the world, they will be quickly learned by others, which in turn threatens Zhao Song's safety.

Therefore, the casting and artillery bureau, which is deeply trapped in the category of mud models, is really clueless about the current process improvement.

There are two cast long-barrel cannons in the workshop of the third group. Their performance is pretty good, and their range and accuracy are improved compared with previous finished products. However, their weight is also increasing accordingly.

Therefore, the most important point of the third group now is to show the most appropriate model.

How big is the diameter of this ten-pound cannon (twelve-pound cannon) that is most suitable?

——Dimensional diameter refers to the ratio of the length of the barrel to the diameter of the barrel. The larger the diameter, the greater the range and relative accuracy.

But as the head of the third group, Fanning also needs to think about the improvement of technology.

A boy who graduated from a technical school two days ago proposed an idea.

Although Fanning focused on multiplying, he still had to spare his brain to consider the craftsmanship.

In the past three years, more than 100 artillery pieces of large and small have been cast by the Cast Artillery Bureau.

And more are scrapped.

Among the latter, not only are there many waste products that are "born" with congenital disabilities, but there are also many that look like they don't have any problems with their appearance, but once the shot is tested, they will explode.

The boy thought that this was because the inner and outer walls of the gun barrel were unevenly cooled, which led to invisible cracks on the inner walls of the gun barrel, so it was not useful.

To be fair, Fanning believes that this conclusion makes sense.

When the cast gun barrel is cooled, the outer wall area of ​​the gun barrel is larger than the inner wall and the external air circulation is faster than that of the inside of the gun barrel, which naturally causes the outer wall to cool faster than the inner wall.

The larger the caliber, the more likely it is to have such problems, because the larger the caliber of the cannon, the larger the area gap between the inner and outer walls of the barrel will be, and the cooling speed gap will naturally become larger. It is really possible that hidden cracks will appear on the inner wall of the barrel. Wouldn't such a cannon explode when tested?

But the truth makes sense, so how should we solve it?

Although Fanning has already reported to the top, he still wants to solve this problem by relying on his own abilities.
Chapter completed!