Hong Tao provided Qi Zu with several new ideas, he first drew a very strange cannon on the paper, there was a large rectangular opening near the tail of the cannon, and several small iron cylinders with ears were drawn next to it, which made Qi Zu confused. He couldn't figure out how the shells were easy to reload with such a big opening in the back of the artillery, but how to get out? It's not a matter of air leakage, it's all the air running through the opening in the back.

In fact, this kind of cannon will not be so useless, it is a kind of rear-loading artillery invented by Europeans in the fifteenth century, and then introduced to the Ming Dynasty by the Portuguese, people call it Franc machine cannon.

This cannon was originally a smoothbore gun, without rifling, and the small iron barrel with ears was its charge barrel and gun bolt. When used, this device, called the cartridge, is stuffed through the long opening at the back of the gun, and then fixed with a wedge, and then the gun can be ignited.

Its advantage is that after firing the cannon, the wedge is knocked off with a hammer, and a new heart barrel is immediately replaced, and then fixed with a wedge, and the cannon can be ignited again, and the rate of fire is very fast. But it also has big drawbacks, the seal between the barrel and the barrel is very poor, and the air leakage is serious, so the firing range is not ideal.

However, Hong Tao believes that relying on the current casting and metalworking capabilities of the Jinhe Empire, it should be possible to create more precise barrels and barrels, so that they can fit more together, reduce the amount of air leakage as much as possible, and maybe increase the range of fire without reducing the rate of fire. In fact, at present, it is not too far to use the firing range, since it is a rifled gun, it must be much more accurate than the smoothbore gun, the effective firing range can reach one kilometer, and with a certain degree of accuracy, it is enough to suppress the front-loading smoothbore gun.

"It's not that difficult, you can try it. However, there is a problem, if the caliber of the cannon is larger, the weight of the cartridge will inevitably increase, and after firing, it may be very troublesome for the gunner to replace the hundreds of pounds of hot cartridge. If the caliber of the cannon is larger, it will be difficult to move. "Qi Zu is a standard cannonist, he always wants to raise, raise, and raise the caliber of the cannon, there is no end to it, and he will never be satisfied.

"Okay, what you said makes sense, so let's look at the second way." For things that he is not sure about, Hong Tao is indeed very modest. What Qi Zu said also makes sense, this modified Franc cannon, the smaller the caliber, the better, once the cartridge is too heavy, it is really troublesome to replace.

The second type of bolt closure device is actually very similar to the bolt door that Qi Zu originally made, Hong Tao only slightly changed the changes, but from the picture, it is much more reasonable.

How did it change? It is very simple, that is, divide the threads in the original gun chamber into four equal parts, and file the left and right parts of it. Then turn the threads on the bolt into the same four equal parts, and file the upper and lower parts. In this way, the threads of the bolt and the breech are staggered, and when the two are stuffed together, the threads protruding from each other are exactly in the position where the other party is filed, and there is no need to screw it at all, just plug it in.

At this time, the point comes, as long as the bolt is turned 90 degrees, the bolt and the remaining two threads in the chamber will bite together, and then the bolt will be fixed at the tail of the gun. As for whether these two threads alone can withstand the pressure of the chamber, Hong Tao thinks it should be. If you can't, it doesn't matter, then add a few more until you can withstand it, at most add a little longer and weight to the tail of the gun.

In fact, this structure was not invented by Hong Tao, although it was not very commonly used in later generations, it will also be seen in daily life. Some medicine bottles and beverage bottles are used for fast opening and closing, and it has a scientific name called intermittent thread.

Its advantage is that it can be fixed quickly, and only needs to be twisted 90 degrees. If it's still too troublesome, then divide the thread into sixth, eighth, tenth, and twelve...... Anyway, the more points you have, the smaller the angle at which you need to turn the bolt, and the better the stability.

Of course, it also has disadvantages, that is, the processing accuracy requirements are relatively high, and the strength requirements for steel are also relatively high. Not only do these threads have to be fastened, but they also have to be able to withstand hundreds or thousands of high-bore pressure impacts. In addition, there is another problem is the sealing, the thread of the whole circle can not completely seal the high-pressure gas, and now it is made into several sections, and the sealing effect is definitely worse. It is impossible to rely on machining accuracy alone to make the contact surface without threads seamless, and even high-pressure gas can not be drilled, not to mention the current technology, even if it is put on the CNC machine tools of later generations.

Then the problem arises again, the high-temperature and high-pressure gas when the gunpowder is deflagrated is cauterized. It doesn't matter that there is no intricate structure in the chamber, but these tightly bitten threads are afraid. Once there is too much air leakage, there is still a lock-up situation. On the battlefield, if the bolt can't be opened, then the cannon will be completely useless, and there will be no time to repair it.

But in any case, the problem of loading speed is solved, and the remaining problem is how to seal, compared with the full-threaded gun latch, the two problems have become one, an improvement of 50 percent, as long as the sealing problem is solved, the intermittent threaded gun bolt can be used.

"It's that simple! Why didn't I think of that? This idea is so good, the accuracy is no problem, first set out the general texture, and then file slowly by hand, absolutely regular! Hey, hey, hey...... Why is it so annoying! A few less threads, and this problem is solved, hahahahaha...... Xiao Qi, go find Boss Xu and let him go full speed, this is too slow, when will he arrive! ”

Qi Zu was stupid when he heard it, his original design was so close to success, only a dozen centimeters away, and he was stunned to torture himself for more than a year. Now even if he is asked to return to Jinhe City to be the prime minister, he will not go, with Hong Tao's intermittent threaded structure, his dream of building cannons and giant cannons will soon be realized. Remembering that the cannon he had built could destroy the enemy's warships for miles away, he also wanted to grow wings and hurried to Cape Town. No matter how good the idea is on the ship, it is useless, there is no condition for experimentation here!

"Don't go yet, I still have a way, this is the most reliable, don't you want to hear it?" Wen Xiaoqi was very depressed, he was pressed down by Qi Zu when he got up just now, and he was held down by Hong Tao again this time. He has already thought about it, who is willing to go to Xu Liangzhi next time, he will not go!

"And! More reliable than this? If it weren't for the fact that Qi Zu was more than ten years older than Hong Tao, he would have thought of kneeling down and kowtowing to Hong Tao immediately. It's all so perfect, isn't it the most reliable, is this still a human brain?

"Hey, hey, hey...... There is indeed another one, which is a little more complicated, and I will talk about it when I draw it. "Hong Tao is so beautiful, looking at the eyes of Qi Zu and Wen Xiaoqi with adoration and worship and worship, he will not die unjustly. What are you waiting for, hurry up and put pen to paper, let the two of them see if Lord Ma has three eyes!

The design of the last gun latch is really the gun door that existed in history, this thing is from the book, and its name is the horizontal wedge gun latch. Pseudo-military fans are also military fans, and the brand-name product Krupp in the artillery used this kind of wedge gun bolt in the early after-loading gun, which can be known with a little understanding.

To put it bluntly, this kind of cannon latch is a large wedge-shaped steel bump with a hole as thick as the gun chamber, which is inserted horizontally into the opening at the tail of the artillery, like a door latch at home. When loading, pull out the bolt horizontally, so that the hole on the bolt is aligned with the breech, and the warhead and the medicine bag can be stuffed in. Then push the bolt back to block the mouth behind the breech, and then plug the pull fuse through a small hole in the gun body, pierce the medicine bag, and pull the rope...... With a bang, the cannonballs went out.

The advantage of this kind of bolt is that it is easy to process, much easier than intermittent threads, and the material requirements are not high. The disadvantage is that there is still an air leak between the bolt and the rear mouth of the breech, which requires a metal device called a closed air ring to overcome.

Hong Tao has seen the breath-closing ring in a book, which is a metal circle made of alloy, and the cross-section is L-shaped. Correspondingly, an L-shaped groove should be milled out of the edge of the rear mouth of the gun chamber, just enough to put the closed air ring into it.

As for whether this structure can prevent excessive air leakage, Hong Tao thinks it should, maybe, and probably be. Because many cannons in history were made like this, and everyone succeeded, why didn't they succeed? But in the end, it didn't work out, and you had to go to Cape Town to really try it to know. After all, I'm not a real military fan, and I don't have a match for this kind of thing, and if I haven't studied it carefully, I may miss a certain part.

"If it's a large-caliber gun, the weight of this bolt is not light, right? Will it be more difficult to operate? Qi Zu still remembered his dream of a giant cannon, no matter what he considered, he always magnified the parts several times first.

"No, there should also be a screw locking device here, like the movable wrench I designed, which can be brought out by rotating the screw, not by human pull. It's just that I can't draw well, it's too fine, and when I get to the port of Cape Town, I will find a professional cartographer to help me draw one, and you will understand. "Hong Tao's sketches are really called sketches, and people who don't know much about these don't know what he draws.

"No need to draw, I understand! An active wrench is one in which the screw does not move and the wrench slides. Now His Majesty has reversed it, the wrench is the barrel, the screw is the latch, the wrench does not move the screw, and this latch can rely on the rotation of the screw to enter and exit freely! "Qi Zu is a professional in this, and every sentence Hong Tao says will automatically become a structural diagram in his mind, which is still three-dimensional. With the example of the wrench, he instantly understood what Hong Tao meant, even more than Hong Tao. Because Hong Tao just said this, he didn't know how to implement it, but he even had a rough idea of how to install this kind of screw device on the latch.

"Your Majesty, do you say that this kind of air-closing ring will work on my steam engine? It can seal the high-pressure gas in the cannon, and there is no reason why it can't seal the water vapor in the boiler. "Wen Xiaoqi doesn't care about the cannon, he only pays attention to what he can use. He was fascinated by the theory of metal air closures, and it would be great if they could be sealed with metal.

"I'm afraid it's enough to choke, as far as I know, this kind of closed air ring uses high bore pressure to achieve the sealing effect. You see, it's right on the plane of the bolt sealing the breech, and if there isn't enough pressure, there will definitely be a gap between it and the bolt. However, the instantaneous high temperature and high pressure in the barrel will deform the metal air closure ring, and it will be pressed on the plane of the gun latch, almost to the extent that there is no gap, so as to achieve the sealing effect. According to this way of working, it should be more appropriate to use copper for this kind of closed air ring, which can maintain a certain strength and is easy to deform. As for whether we need alloys or not, we have to go to Cape Town to test them slowly. Hong Tao does not support Wen Xiaoqi's speculation, and the working principle of the closed air loop does not seem to be suitable for the relatively low-pressure and low-temperature environment of the steam engine. But this possibility cannot be ruled out, it is still the same sentence, practice is the only criterion for testing the truth, whether it is right or not, whether it is successful or not, it is useless to just say, try to know.

"Boss Xu! Boss Xu! Full sails, full sails! Such a good wind, raise the rope sail and the pole sail! Wen Xiaoqi and Qi Zu seriously agreed with Hong Tao's suggestion with practical actions, they must rush to the port of Cape Town as soon as possible, they can't do anything but discuss on the ship, and they can't even discuss without practice. This time, the two of them rushed to the door of the cabin in unison, and shouted to the deck. Especially Wen Xiaoqi, he is a shipbuilding family, don't look at the fact that he has never studied in the navigation school system, it is his instinct to sail a ship, no worse than a naval officer.

(To be continued.) )