A ship from Belarus?

Deputy Director Huang didn't understand why a ship from Belarus could make Chen Geng and Xie Minsheng so excited? But soon, he understood: out of curiosity, Deputy Director Huang, who followed Chen Geng and Xie Minsheng to the port, looked at the huge frame lifted from the ship with a heavy crane, and was speechless in surprise. Pen % fun % Pavilion www.biquge.info

What a big frame!

"I'm a good girl! That's too big, right? Looking at the behemoth in front of him, Deputy Director Huang couldn't help but exclaim: "One, two, three, four...... 12 shafts? Oh my God, wouldn't that be 24 wheels?! ”

No wonder Deputy Director Huang is so surprised, it is really that the frame in front of him is a little too big, in order to facilitate transportation, this MAZ7907 is removed from the wheels, removed all the bodywork, and even the cab, gas turbine and generator are also dismantled and packaged separately, this is a huge frame with a hub motor, but it is this huge frame, it is also quite shocking!

12 axles are just that, although strictly speaking this huge frame does not have a real sense of "axle", this frame is each wheel is suspended independently by double wishbones, and there is no hard axle to connect the wheels located at both ends of the axle, but the key is that this frame is too big: the visual length is close to 30 meters, and the width has to be more than 4 meters, in order to facilitate transportation, the tires and wheels have been removed, but just look at the tires placed aside, the height of each tire will not be shorter than their own, A huge frame that can fit 24 wheels!

I didn't see the engine, but there were several huge boxes being hoisted down from the ship, presumably from the car. There was no man who was not interested in this kind of machinery, so Deputy Factory Director Huang couldn't help but ask Chen Geng and Old Man Xie: "Chen Dong, Mr. Xie, what is this thing for?" Lao Maozi's special engineering vehicles? ”

"That's right," Chen Geng looked at the big guy in front of him with bright eyes, and nodded absentmindedly: "It's used to transport land-based ICBMs." ”

"it!" Deputy Director Huang's eyes were dark, and he almost fell: This big guy turned out to be a carrier of a land-based ICBM?! Do you want to exaggerate so much? Cautiously, Deputy Director Huang asked Chen Geng: "Brother, what are you doing with this thing in Runhua Industry?" The carriers of our country's ballistic missiles are all from the Sanjiang special car, right? ”

"Oh, I think the special engineering vehicle industry is more promising," Chen Geng said: "For example, heavy cranes, heavy pump trucks and other things, you can't do without a heavy chassis, this time I met this thing in Belarus, so I took it for reference." ”

"......" Deputy Director Huang was speechless: You Runhua Industry actually want to make the chassis of special vehicles? !

"Think we can't do it well?" Looking at the appearance of Deputy Director Huang, Chen Geng smiled.

Of course, he knows why Deputy Director Huang has such an expression, in some indicators, the requirements for civilian special chassis vehicles are even higher than the requirements for military special chassis vehicles, the most critical of which is reliability: a heavy crane with a lifting weight of more than 100 tons, suddenly interrupted when the lifting is halfway through, how to calculate this loss? ：

The crane is also good to say, this kind of vehicle has an emergency safety device, so that it will not be lifted to half of the thing "bar" and fall down all of a sudden, but if it is an infrastructure project, what about the concrete pump truck that is necessary for the summary? In the construction of water conservancy projects, there is a strict limit on the time of pouring concrete, this thing will solidify, you water the general pump truck breakdown, resulting in the whole project problems, who can afford this responsibility?

For these reasons, all the heavy civil engineering vehicles in China are imported, and all of them are Mercedes-Benz, Volvo, MAN and Scania, which are the top European goods, and the small Japanese cars are not looking at it at all.

The smile was full of pride, and Chen Geng said: "Deputy Director Huang, you have to believe that if others can't do well, it doesn't mean that we Runhua Industry can't do well." ”

Deputy Director Huang raised his eyebrows, obviously a little unconvinced: Who wouldn't say big words? Maybe that's the way to do it.

It's no wonder that Deputy Director Huang is such an expression, technology has always been gradual, no one can leapfrog forward, saying that Runhua Industry can make a good truck, Deputy Director Huang also thinks that there are some possibilities, but they can make a heavy engineering vehicle chassis that engages in reliability?

If things are really that simple, why did our country spend a few years ago to introduce heavy truck technology from the Austrian Steyr company? In addition to bragging, Deputy Director Huang felt that he could not find any other explanation.

In the face of Deputy Director Huang's suspicion, Chen Geng did not explain, not that Chen Geng did not want to explain, but this kind of thing could not be explained at all, before the product was made and passed the strict inspection of the market, no one would believe his own words, since his explanation was not popular, why did he bother to do that?

………………………………

It took four days for Runhua Industrial to finally assemble the MAZ7907.

Looking at the behemoth in front of him, Chen Geng's mood was that of Aunt Sauce: "! It's huge. ”

"yes, that's big." Old Man Xie nodded again and again.

......Pascal Schultz did not speak, but his eyes were a little frightened: this is the nuclear cloud that once hung over Europe.

…………

Liao Qian was more straightforward, pointed to a bulging lump at the position that was supposed to be used for camel-borne SS-24 ICBMs, and asked Chen Geng curiously: "Chen Dong, how can there be a set of diesel generator sets there?" ”

"Ahem......" Chen Geng couldn't help but feel a little embarrassed.

Because he couldn't find an expert who could inspect and repair the GTD-1250 gas turbine on the MAZ7907, for the sake of safety, Chen Geng decided not to install the generator set driven by the GTD-1250 gas turbine for the time being, in order to let this big guy move first. The engineers of Runhua Industry adopted another workaround: directly moved a set of diesel generator sets powered by the 12V190B diesel engine produced by the 882KW Shungeng Diesel Engine Factory to this MAZ7907 which one is - anyway, there is enough space on this car, and there is no place to install it.

Compared with the 1250 horsepower GTD-1250 gas turbine on the MAZ7907, the Jichai 12V190B diesel engine with 1199.5 horsepower and 12 hours of continuous power can be said to have basically no gap with the GTD-1250 gas turbine in terms of power generation capacity...... Anyway, the 12V190B diesel engine, which weighs up to 5300 kg, is much larger than the GTD-1250 gas turbine, which weighs less than 500 kg.

It was precisely because the original GTD-1250 gas turbine generator set was replaced with a 12V190B diesel generator set that the MAZ7907 took four days to reassemble, but in any case, it was a bit embarrassing......

Wang Ke, the engineer responsible for the installation and maintenance of the car, reacted quickly, and looked at the boss a little embarrassed, he immediately said: "Chen Dong, we have tried, the car is fine, it can be started now, you can see ......"

"Well, this is not in a hurry," Chen Geng coughed twice, and pretended to be calm: "The circuits of the car have been overhauled, right?" This car has been parked in the open for several years, don't leak electricity or something. ”

"Don't worry," Wang Ke immediately said: "We have overhauled the circuit, repaired the repair, replaced the replacement, to ensure that there is no problem at all, but the electronic control and rectification of this car is too backward," Speaking of this, Wang Ke looked disgusted: "I don't know if I haven't seen it with my own eyes, a car with such a powerful performance, rectifier, clipping is still used in tubes." ”

"What? Still rectified with tubes? Chen Geng was stunned for a moment, thinking that he had heard it wrong.

At that time, the acquisition and transportation of this MAZ7907 was followed up by Dong Minzhu throughout the whole process, Chen Geng didn't even see the car, so naturally he couldn't understand it, but how could he not understand, he also knew that the tube rectification was too late, and what era of technology was the tube rectification? In the 40s, compared with the GTO (Gate-Switch-Off Thyristor Widely Used Today), the efficiency of tube rectification is simply low - it stands to reason that the efficiency of electric transmission is higher than that of mechanical transmission, but with this rectifier system, the transmission efficiency of this all-electric drive MAZ7907 is not as good as that of traditional mechanical transmission.

Chen Geng somewhat understood why the Soviets wanted to electrify this MAZ7907, instead of the mechanical transmission that had been used since the MAZ7904 era: there were so many wheels in the 7907 that Lao Maozi couldn't figure out the problem of interaxle load interference caused by mechanical transmission, and finally had to give up the mechanical transmission altogether - there is a hub motor on each wheel of the 7907, and a wire is directly drawn to the motor, so naturally there is no interference of the load between the axles.

However, although the problem of load interference between the shafts has been solved, the rectification efficiency of the electron tube is too low, which directly leads to the low transmission efficiency, and finally leads to the maximum speed of this MAZ7907 is only 25 kilometers per hour.

"Yes," Wang Ke nodded: "I calculated, if you use GTO, the maximum speed can be increased to 28 roads and 30 kilometers per hour." ”

Chen Geng frowned and said, "What if you use IGBT?" ”

IGBT, insulated gate bipolar transistor, in the early 80s by the United States General Electric and RCA company jointly developed, from the moment of birth, IGBT with high efficiency, small on-state voltage drop, large current-carrying density, high withstand voltage and power MOSFET drive power, fast switching speed, high input impedance, good thermal stability advantages and favored by the market, the most important thing is that IGBT to improve the performance of power electronic devices, especially for the inverter miniaturization, high efficiency, low noise provides favorable conditions, Since Wang Kedu thought of GTO, why not use IGBT directly?

Wang Ke's answer is very simple: "IGBT is all imported, which is expensive." ”