Chapter two hundred and fiftieth chapters are righteous
Niu Shilong had a victorious look on his face and looked at Qin Zhenhua from time to time. Ma Panshan and Zhou Xuejun also came over. They always maintained their normal meeting postures and turned a blind eye to Niu Shilong's showy look.
Niu Shilong finally became the leader, and at this important meeting, their Coal Province Diesel Engine Factory stole the show. It can even be said that this meeting was mainly held for them.
Now, everyone is listening carefully to the design plan of their own tank engine.
Finally, their report ended, and Minister Zhu continued: "Now everyone can put forward some opinions on these two plans. Well, who comes first?"
At this time, there will be a brief silence. After all, such comments must be fair and objective, cannot be selfish, and must be made clear. This is a major event that determines the development of the domestic tank industry.
The veteran experts were still thinking about it at this time, but Qin Zhenhua raised his hand: "Dear leaders, I have an opinion, can you tell me?"
"You? Do you know about engines?" Niu Shilong couldn't help but murmured next to him. Isn't it just a small improvement in the armor-piercing bullets through your relationship? The engine is different from the armor-piercing bullets. Is there anything in it?
Do you understand how many parts it consists of?
However, such words can only be said in a low voice. After all, anyone who can participate in this meeting is qualified to comment.
"Oh, Xiao Qin, tell me." Minister Zhu saw it was Qin Zhenhua with a smile on his face. Although Qin Zhenhua was young and his qualifications were not enough to convince the public, in recent times, he has made one after another
Astonishing achievements, if nothing else, taking the introduction of the L7 tank gun as an example, it was his first achievement.
"Well, then I'm offended." Qin Zhenhua stood up and said this, obviously trying to find faults.
"First of all, let's talk about our X150 engine. From the current point of view, this engine should have the possibility of being successfully developed." Qin Zhenhua began to comment.
Isn't this nonsense? Niu Shilong cursed secretly there, you boy, are you here to find fault in an open and honest manner? Well, if you want to find fault, it won't be difficult for us, our technology is the most advanced.
"This engine utilizes the body of our existing 12150L engine to the greatest extent, which can reduce the risk of research and development and make it easier to modify existing vehicles. However, precisely because of this, it inherits the long stroke of the 12150L
, small cylinder center distance and weak machine body, it can be said that the X150's power improvement potential is very limited." Qin Zhenhua said: "It is not easy for it to reach 700 kilowatts. If it wants to continue to improve, it will probably be even more difficult.
It is getting even more difficult, and what about our future tanks? They will also need at least 883 kilowatts, which is 1,200 horsepower. I think if we take this route, we will reach a dead end."
"Pa." In this kind of meeting, Niu Shilong is supposed to restrain his leadership style. There are too many leaders who are older than him, so when he stood up and slapped his palms on the table,
Then I felt something was wrong.
"I'm sorry, leaders, I couldn't control my emotions." He quickly apologized to the leaders, and then said: "However, Qin Zhenhua has gone too far to deceive others, and has reduced our research and development to nothing. Qin Zhenhua, what are you doing?
?”
Of course Niu Shilong was angry.
He was waiting for everyone to praise him. He had proposed two plans. One of them would definitely satisfy the leader, and even both of them could satisfy the leader. Who knew that after just finishing his speech, Qin Zhenhua, who was the first to speak, gave them They poured cold water on it, saying that their plan was a dead end.
If the speaker is an old expert or a famous scholar, he can still accept it, but if the speaker is Qin Zhenhua, how can he accept it?
In fact, even in this kind of meeting, it is possible for various units to quarrel with each other for their own interests. After all, we have a famous saying that the truth is refuted, and everyone should express their opinions. But, what qualifications do you, a young apprentice, have to say that there is something wrong with our engine?
Faced with this question, Qin Zhenhua had an unnoticed sneer on his lips: "Director Niu, I just said that the stroke is long, the cylinder center distance is small, and the machine is weak. Do you know what this means?"
"I don't care what you mean..." When he said this, Niu Shilong suddenly stopped. He had already understood that in a meeting of this level, this Qin Zhenhua deliberately provoked himself to speak, just to expose that he did not understand. This technical flaw was just a matter of making a fool of myself in front of the entire factory in the skills competition. Now, if I show that I know nothing about technology in front of so many leaders, I will be in big trouble. No, the top boss I worked so hard to get is the top boss of a factory with great development prospects. I'm afraid this job will go to waste.
"Okay, you should tell me about it." Niu Shilong skillfully kicked the ball back. I don't understand, but everyone present understands. You should tell me about it and let everyone see your level. .
Qin Zhenhua was just waiting for this sentence to explain it clearly to everyone.
"We know that to improve the power of the engine, we can start from two aspects." Qin Zhenhua said: "On the one hand, it is to increase the efficiency of a single cylinder. The higher the combustion efficiency, the larger the cylinder volume, the more power. On the other hand, , that is, to increase the speed. When we cannot increase the power per cylinder, we can increase the speed."
Niu Shilong paid careful attention to everyone's reactions and found that even Zhang Baolin was listening carefully. It seemed that what Qin Zhenhua said was okay?
"With our existing engine, due to innate limitations, the speed cannot be increased. The original body of the 12150L determines the distance the piston moves up and down. In this way, once the speed increases, the inertia of the reciprocating motion becomes greater. Therefore, the engine The maximum speed is about 2,200 rpm. Looking at the German Leopard-2 tank diesel engine, the speed is increased to 2,800 rpm to reach 1,500 horsepower." Qin Zhenhua said: "This is the problem caused by the long stroke. "
"Let's talk about the cylinder distance, which is the heavy distance between two adjacent cylinders. The ratio of the cylinder distance to the bore of the 12150L is 1.17. This ratio is almost unique among similar engines. Although this design can meet the requirements of small engine length and volume. It has a series of advantages such as small size, high power per unit volume, light weight, etc., but it also brings many disadvantages."
Qin Zhenhua kept talking and explained to everyone that because this distance is small, the length of the main journal of the crankshaft and the connecting rod journal is shorter, and the thickness of the crank arm is smaller. On the one hand, the bearing load is increased, and on the other hand, the bearing load is increased.
On the one hand, the stiffness and strength of the crankshaft are poor.
Because this distance is small, the thickness of the crankcase diaphragm is also small, making the crankcase less elegant.
As for the biggest problem, this reduction in distance results in a smaller cooling water channel circulation area in the cylinder body, which affects the cooling of the cylinder and the rigidity of the cylinder body is poor.
The gas wall thickness is thin, the stiffness is insufficient, and it is easy to deform. Even the cylinder liner is not stiff enough to cause high-frequency vibration during operation. If this diesel engine is forced to increase to 1500 rpm, it will produce terrible vibrations.
Resonance becomes a constraint on performance improvement.
Qin Zhenhua's performance was not just a partial understanding, but a clear and logical analysis of various issues. Everyone here agreed with Qin Zhenhua's opinions. Even Zhang Baolin could not express any objections for a while.
"As far as I know, the existing diesel engines under development will blow out the cylinder head, and if the power continues to be increased to 700 kilowatts." Qin Zhenhua said: "By then, the cylinder head blowout will probably be an unsolvable problem.