Chapter 1223: Zhang Baozhong's baby

"Mr. Tan, in fact, I know what you mean by coming. I'm afraid it is mainly to discuss with me whether the 12150ZL can be used for civilian use."
Tan Zhenhua nodded, without denying it.
Wang Baozhong thought for a while and said, "Of course it is possible, but I don't recommend it."
"Uh, can you ask why?" Tan Zhenhua suddenly felt that he poured cold water on people's head-saying that he was tossing about the diesel engine was really not small, but today he suddenly discovered that he had forgotten the most important point. He did not seriously discuss with Wang Baozhong the fundamental issue of whether this engine could be converted to civilian use!
At this moment, he suddenly became vigilant and realized that, unconsciously, he had developed a very bad mental inertia-because in the past few years, he was too successful, and these successes were somewhat It is based on the ability of his rebirth gold finger to open and hang, and some are obtained by virtue of his growing financial resources and growing reputation. He has gradually become accustomed to his omnipotence and gradually You have to become more and more conceited, thinking that everything should follow your own trajectory, but this is actually just an illusion!
Tan Zhenhua realized his problem at this moment and couldn't help but fall into a short trance. Wang Baozhong obviously saw that his expression was different, but he would be completely wrong, thinking that he was losing the 12150ZL because he could not civilianize it. Speaking comfortingly: "But Mr. Tan, I have always had another idea about civilian products. Do you have time for us to discuss it?"
When Wang Baozhong said that, Tan Zhenhua immediately returned to his soul and said quickly: "I have time and time. This is what I came for. I don't know anything about diesel engines. I would like to ask Mr. Zhang for more advice."
Wang Baozhong smiled slightly, and was very satisfied with Tan Zhenhua’s humility, so he thought about it a little and sorted out his own thoughts, and said:
In fact, as far as diesel engines are concerned, the difference between civilian and military is not much. Most of the technologies are common, but, military products are pursuing various extreme conditions, such as low-temperature starting performance, short-term power improvement, high reliability, etc., which are becoming more and more important for fuel consumption and the civilian market. The pursuit of environmental protection indicators pay less attention; what about civilian use? Generally, they do not require extreme performance. In order to pursue service life and fuel economy, they will also limit their speed, power, cylinder pressure and other indicators. Now the most advanced in the world Diesel engines are often equipped with emission after-treatment systems to ensure environmental protection indicators. These are typical differences between military and civilians."
Tan Zhenhua nodded and approved Wang Baozhong’s statement. Wang Baozhong went on to say:
Speaking of this 12150ZL engine, its prototype is actually the B2-54A tank diesel engine we imported from Soviet Russia back then. The standard power of the prototype is 382 kilowatts ( 520 horsepower). It was finalized in China and put into mass production in 1958. The B2 diesel engine should be said to be a relatively successful model. It has a 4-stroke, 12-cylinder, water-cooled, V-shaped layout with an angle of 60° and a solid structure. , The torque output is uniform, the rigidity of each part is relatively good, the length of the crankshaft is short, so its anti-torsional vibration performance is better, the weight of the engine is also lighter, the layout of the accessories and the height, width and volume of the external dimensions are compared ideal.
This diesel engine uses a small cylinder center distance, the cylinder center distance is small, the ratio of the cylinder center distance to the cylinder diameter is 1.17, this ratio is rare in similar engines, the use of such a small cylinder center distance is to meet the engine length The overall design requirements of small size, small size, high power per unit volume and light weight.
However, these advantages are also disadvantages in a sense. The biggest problem is that it is difficult to develop V-shaped 8-cylinder, 10-cylinder and other serialized products on this model due to the 60° cylinder angle arrangement. So we Failed to do any engineering practice in this regard, but developed an inline 6-cylinder model based on this diesel engine, which is mainly used for artillery towing vehicles and armored vehicles.
Moreover, the small cylinder center distance design adopted by this diesel engine also brings a series of other shortcomings:
The length of the main journal and connecting rod journal of the crankshaft is short, and the thickness of the crank arm is small. The former increases the bearing load, and the latter makes the rigidity and strength of the crankshaft poor;
The thickness of the crankcase diaphragm is small, which makes the demeanor of the crankcase poor;
The cooling water passage in the cylinder block has a small circulation area, which makes the cooling water flow rate higher, which affects the cooling of the cylinder, and because the thickness of the cylinder block diaphragm is small, the rigidity of the cylinder block is poor;
The gas wall thickness is thin, the rigidity is insufficient, and it is easy to deform. This must increase the gap between the piston and the cylinder liner, which makes the piston group difficult to work; the lack of rigidity of the cylinder liner can easily cause it to produce high-frequency vibration during operation, resulting in the cylinder liner Cavitation with the cylinder block.
These shortcomings are detrimental to the life and working reliability of diesel engines.
Of course, there are more problems, but Mr. Tan, you are not a professional technician, so you don’t need to understand it in such detail. In short, this type of diesel engine is used as a military power and meets the requirements, but if it is used for civilian use, whether it is economical There are still some other properties, which may not be suitable, and there is little potential for improvement. "
Tan Zhenhua listened to Zhang Baozhong's very professional knowledge for a long time, and couldn't help but feel a little dizzy, but fortunately, he understood the last advice: "The 12150ZL engine can be used for military purposes, but it can be used for civilian purposes. , It’s too old, it consumes fuel, and there is no room for tapping the potential for transformation."
Before he gave up his mind, he immediately noticed another contradiction. Just about to ask a question, Zhang Baozhong had already guessed what he was thinking and explained directly: "Mr. Tan, you want to ask, why I said that there is no room for development of this engine. Why can we increase the B2 engine from the prototype of 382 kilowatts and 520 horsepower to the current 537 kilowatts of 730 horsepower? This is actually the result of adding an exhaust turbocharger mechanism to the prototype. This project started in 1970 It started in 1983, and it took 13 years before and after it was finally finalized in 1983. You must know what the reason is, Mr. Tan, but fortunately, the product has now reached the design requirements, after so many years of continuous testing and improvement. This type of engine should be said to be mature in general. That’s why I would like to use this power to bid for the Pakistan Railway project.

Tan Zhenhua nodded silently. Some words don't need to be said clearly, but he can fully appreciate that in those years, the group of Chinese scientific researchers led by Zhang Baozhong insisted on their ideals under the difficult conditions.
Zhang Baozhong’s words cut off from the technical level Tan Zhenhua’s idea of ​​using this 12150ZL engine to impact the civilian market. This made Tan Zhenhua who had come from the booming industry quite disappointed. However, thinking of his hint when we first met, Tan Zhenhua felt that this Zhang Gong was sure in his hands. What's hiding baby!