The 5TDF engine is one of the most unique inventions in the field of power units. It was invented in the Soviet Union. A distinctive feature is that it was not designed for cars at all, but for a tank like the T-64. However, his unusual design brought him the most popularity.
General description of equipment
The 5TDF engine was a five-cylinder. Only this fact already made him rather unusual. In addition, he had 10 parts such as connecting rods and pistons in his design. In addition, two crankshafts were used here simultaneously. Pistons in cylinders made unusual movements. They moved towards each other, then back, again towards each other, and so on. In this case, power was taken from both crankshafts to make it as convenient as possible to control the tank.
The principle of operation of the 5TDF engine is two-stroke. In this case, the pistons of this device played the role of spools. They opened both inlet and outlet windows. In other words, no valves or camshafts were used in this case.
Because of all the features that were described above, it turned out that the design of the 5TDF engine was as efficient and brilliant in some ways. This was explained by the fact that the two-stroke cycle of operation provided maximum liter power during engine operation, and its direct-flow purge provided high quality filling of the cylinders.
Unit Injection
The 5TDF engine was also distinguished by the fact that it was a diesel unit with direct injection. It is understood that the fuel was supplied to the desired space between the pistons a few moments before they reached the maximum approximation. Another feature here was that, firstly, the injection itself was carried out by four nozzles, and, secondly, it went along a rather cunning trajectory, which ensured the fastest possible mixture formation.
Other design tricks
The tricks and features of the 5TDF engine did not end at all with what was listed above. There was another highlight that was hiding in the turbocharger. The turbine itself was quite large and, together with the compressor, was located on the shaft. In addition, she had a mechanical connection with one of the crankshafts of the engine. This decision is considered brilliant. Firstly, during the acceleration of the tank, the compressor was slightly twisted due to the shaft torque, which eliminated such a drawback as a turboyama. After a sufficiently powerful stream of exhaust gases was formed and the turbine spun up to significant revolutions, the power that it gained was transferred, on the contrary, to the crankshaft. All this increased the efficiency of the power unit, and the turbine itself was called the power unit.
It is also worth mentioning another important characteristic of the 5TDF engine - it was multi-fuel. In other words, it could be operated on diesel, gasoline, aviation fuel, and any mixture of these types.
In addition to these great design features, the overall design of the device consisted of about fifty small tricks. This could include pistons with inserts made of heat-resistant steel, and lubrication systems with dry sump, and much more.
Engine goals
Naturally, after such a technical description of 5TDF, many may have a question about why this power unit was created, what goals its creators pursued.
All these changes pursued only a few fairly clearly formulated goals. Firstly, the motor should be as compact as possible, and secondly, it should be economical. However, the most important thing is to get enough power to operate such a tool as a tank. The importance of these requirements is explained by the following. Compactness can greatly facilitate the layout of the tank, which means that it can be assembled faster at the factory. Efficiency significantly affects the autonomy of the tank, that is, reduces the need for frequent refueling. Power is important for a tank’s power unit in that it increases such an important parameter as maneuverability.
Work results
All the efforts of designers and scientists who developed this engine model were not in vain, the result of the work was quite impressive. The working volume of the unit was only 13.6 liters, but in the most forced state it had a power of more than 1000 hp. Since this motor was operated back in the 60s, this result was considered beyond praise. In its specific liter capacity, as well as in overall power, this invention was several times superior to any other invention of any army in the world. Due to its layout, this device is often called the "suitcase".
Is the 5TDF engine currently available? It is fair to say that this power unit still did not take root, despite all its significant advantages. He was quite complicated in execution, and also was very expensive.
Equipment operation
Since for some time this engine was still used, that is, certain instructions for its use. Here, a lot of attention is given to materials, namely fuel, which must be filled. Although the device is multi-fuel, diesel has become the main type of its working fluid. Brand selection was based on ambient temperature. So, if the temperature was not lower than +5 degrees Celsius, then the brand of diesel fuel for high-speed diesel engines DL was used. At indicators from +5 to -30 degrees Celsius, another brand was used - DZ. If, at the height of winter, the temperature dropped below -30 degrees Celsius, then YES fuel was used.
Separately, it is worth adding that the fuel grade DZ could also be used if the temperature exceeded the mark of +50 degrees. As in any other engine, this used oil, which was allowed only two types. The main one was M16-IHP-3, however, if it was not available or there was no possibility of topping up at the right time, then it could be replaced with MT-16p liquid. However, when replacing one type of lubricant with another, it was necessary to completely drain the remainder of the previous one from the crankcase, and only then fill in a new one. Boxer engines 5TDF were unique also for these several reasons.
Unit operation on different fuels
In order for the tank to work with different types of fuel, it was equipped with a special fuel supply control mechanism. He had only two positions that could be switched at the right time. The first position ensured operation during refueling with diesel fuel for high-speed diesel engines, fuel for jet engines, as well as gasoline and mixtures of these three types of fuel in any proportions. The second position implied switching the engine operating mode to the use of gasoline only as a working mixture.
There are several features that arise when switching work to gasoline. Firstly, it is necessary not later than 2 minutes before the tank starts to operate the BTSN equipment pump, and then pump the fuel at an intensive pace using a manual booster pump. Secondly, regardless of the ambient temperature, before starting, you need to make a double injection of oil into the cylinders.
Technical specifications
It is worth saying that the technical characteristics of the 5TDF engine are quite high, and in itself it is already the second modification released in 1960. The first was the 5TD, released in 1956. The power of the 5TDF power unit was 700 hp. The diameter of its cylinders was 120 mm. The piston stroke was 2 x 120 mm. The number of cylinders was 5, and the working volume, as already mentioned, is 13.6 liters. The rotational speed was 2800 rpm -1 . There is such a parameter as overall power, which at 5TDF is 895 hp / m 3 . The specific gravity of the power unit is 1.47 kg / hp. Liter capacity, which is characterized as hp / l, is 52. This is a brief technical description of the 5TDF engine.