Life of Being a Crown Prince in France

Chapter 1260: Chapter 1165: Artillery Expert

As for the design of the projectile shape and mold, Cano needs to recommend some talents to take charge.

Joseph does not plan to let his father get involved in other weapon design matters before the steam forging machine is completed.

The next morning, when Joseph arrived at the Royal Armory’s meeting room, the members of the breech-loading cannon project team had not yet arrived—this is where the design work for the breech-loading cannon will be completed in the future.

Joseph saw Cano was already there, sitting in a chair by the window looking at blueprints, so he prepared to discuss the Minie ball with him. However, the director of the Engineering Design Institute saw him first, looking up, and then eagerly approached.

“Crown Prince.” Cano quickly bowed, and then unfolded the blueprints in his hand, “This is an iron cannon barrel that I designed overnight.”

Only then did Joseph notice, the director’s eyes were full of bloodshot, obviously he didn’t sleep much last night.

He was somewhat curious and asked, “How did you come up with the idea of using iron to cast the cannon?”

The mainstream material for manufacturing cannons is currently bronze.

Because bronze has very good toughness, it is not easy to burst, and has a low melting point, making it easy to cast.

Furthermore, the most cutting-edge cannon production mode is to first cast a rough blank, and then use a boring machine to drill out the cannon barrel. This machining method produces cannons that are more robust and the inner wall of the barrel is smoother than directly casting.

Moreover, bronze material is relatively soft, making it easier to drill holes.

Of course, some countries use iron cannon barrels to reduce the cost of cannons. However, due to iron’s poor ductility, to prevent bursting, the thickness of the cannon barrel wall must be increased, causing iron cannons to weigh more than 20% heavier than bronze cannons.

For artillerymen, every bit lighter a cannon is means higher mobility. Thus, iron cannons have never become mainstream.

Cano hurriedly pointed to the blueprint, which depicts a cannon barrel: “Crown Prince, I carefully considered yesterday, the tail fastening bolts and bolt grooves you mentioned are best made of iron because copper is too soft. Under the impact of firing, threads are easily deformed.

“In this way, if we use a bronze barrel, it will create the problem of how to rivet the airtight part between the barrel and tail.

“I think, no matter how good the riveting technique, after multiple shootings, it will become loose.

“So, the best solution is to use an iron barrel, with the tail cast integrally, to ensure the overall reliability of the cannon.”

Joseph looked at the director in surprise; he really had overlooked these issues, while Cano not only immediately thought about them but also drew up sketches overnight.

Joseph first nodded in agreement that Cano’s proposal was indeed stronger, and then hesitated, “But regarding the cannon’s weight…”

Cano immediately showed a brilliant smile, appearing quite proud, “Crown Prince, I looked at the technical documents of the Namur Royal Iron Refinery, their alloy steel’s hardness is 2.5 times that of ordinary steel, and its wear resistance is as high as 4 times.”

Due to the confidentiality of manganese steel, even he only knows it is alloy steel, without knowing the ingredients added.

“If we use this alloy steel to manufacture the inside wall of the barrel, with the outer layer wrapped in wrought iron, then the weight should not exceed that of a bronze cannon. See, this is my calculation process…”

Looking at the dense calculation formulas, Joseph felt a bit overwhelmed, but he trusted the director of the Engineering Design Institute surely wouldn’t make a mistake—this man has authored “Mechanics Overview” and “Positional Geometry,” his basic skills are absolutely solid.

Moreover, he also knows that from the perspective of future cannon technology, iron cannons could even be lighter than bronze ones.

Previously, iron cannons were made using high-carbon steel to ensure barrel wear resistance. Although this material is hard, it is quite brittle, thus the thickness had to be increased to prevent bursting.

Now with manganese steel, a super-hard material, just a thin layer can ensure thousands of shots without wear. Wrought iron or low-carbon steel with high toughness but not wear-resistant is wrapped, used to withstand barrel pressure.

Because the density of iron is much lower than copper, it is entirely possible for the weight not to exceed a bronze cannon.

Joseph nodded appreciatively, “I think your idea is very feasible.”

Currently, in France, under the effect of Patent Law and talent incentive policies, technical talents are highly enthusiastic, coupled with breakthroughs in fine processing technology, various new inventions will certainly see a boom.

Cano’s cannon is just one example.

Cano rubbed his hands excitedly, “I just wonder if there would be difficulties in casting.”

As he was saying this, he saw a slightly chubby man, nearly 1.9 meters tall, walk in, and hurriedly gestured to him: “Mr. Widirina, great, we need your expertise here.”

This burly gentleman is one of the casting experts in the project team.

Several minutes later, Widirina looked at the blueprint with a slight frown, “To be honest, lightweight cannons are no problem, but if it’s a cannon 24-pound or above, the designed thickness of the barrel wall on this drawing needs to be increased by at least 15%, or even 20%.”

Cano felt his technical ability was challenged, protesting: “That’s impossible, I have repeatedly calculated, even with a 15% increase in propellant, this thickness is still enough to withstand the barrel pressure!”

“You overlooked the destructive expansion force caused during the steel cooling process.” Widirina patiently explained, “When the barrel wall is very thick, the temperature difference between the inner and outer layers will be significant.

“When the outside cools and contracts, the inside is still red-hot.

“When the inner layer starts to cool, the outer layer has basically solidified. At this point, the inner layer contracts, causing delamination with the outside.

“You have calculated using the fully cooled steel strength, but in reality, the cast iron cannon is far from being this solid.”

Cano suddenly froze, uneven cooling could indeed reduce the structure strength of the barrel.

Widirina suggested, “Or you can use bronze on the outer layer. You know, bronze’s melting point is very low, so after casting, the alloy steel on the inside layer won’t be heated and softened.”

Cano shook his head dejectedly, “No, using a bronze shell would create the riveting issue with the tail again.”

Joseph suddenly thought of something and looked at Widirina. “So, as long as the inner layer of alloy steel can always maintain sufficient hardness, there’s no need to increase the barrel thickness?”

“Theoretically, yes, Crown Prince.” The latter nodded, “Probably only need to increase about 3% based on Cano’s calculations.”

Joseph immediately said, “Then I have an idea. If we drill holes in the middle of the mold for casting the cannon, allowing cold water to flow through, during the casting process, the inner layer of the barrel can always stay at a low temperature.”

Yes, this is exactly the Rodman casting method that appeared during the American Civil War. Using a very simple technique, it helped extend the lifespan of iron cannons by more than five times.