Legend time
By the beginning of 1940, the final appearance of the V-2 engine was formed. It was a V-shaped 12-cylinder diesel with a cast 4-valve head, power bearing steel studs for added strength, and a centrally located fuel injector. There were also traces of similarities with the aviation AN-1 (it was developed at TsIAM) in terms of the configuration of the connecting rod-piston group. In both motors, the pistons were stamped aluminum with the main and trailed connecting rods, and the bearings were made with lead bronze casting. On the first prototypes of the B-2, the connecting rods were of a fork type and often broke, so it was decided to use trailed connecting rods with a small divergence on the right and left block.
In addition, the tank diesel engine has similarity to the AN-1 with jet mixture formation, but is distinguished by its dimension. For B-2 it is 15/18 (piston stroke / bore, cm), while for AN-1 this parameter is 18/20. It is interesting that the dimension 15/18 for a tank diesel engine was taken from another aviation gasoline engine, the M-100, designed by V. Ya. Klimov. However, all of the above does not mean that the B-2 was born as an aircraft engine. It was originally a tank engine, which in many ways had to be designed according to the patterns of aircraft engine building, since there was simply no other methodological basis for high-speed diesel engines in the Land of the Soviets. And in the 30s, only in the aircraft engine industry was there a sufficiently high level of design and production of such complex equipment. Therefore, the Kharkovites had to turn to the design headquarters of TsIAM for help, which was already mentioned in B-2: the "obstinate horse" of the Soviet tank industry. In addition to the outstanding designer Timofey Chupakhin, Mikhail Petrovich Poddubny made an equally significant contribution to the technological development of production. At KhPZ, he is obliged to develop complex operations for processing crankcase parts, head, crankshaft, connecting rods, specific high-speed processing of sleeve bearings and mandrel of main bearings. In his memoirs, the chief designer of CIAM, Professor, Doctor of Technical Sciences Aleksey Dmitrievich Charomsky, writes that the technologist Poddubny often proposed solutions that were much more progressive than those that came to mind of the designers.
Much time had to be devoted to fighting the gas joint - the diesel was powerful, the copper gaskets simply could not withstand the enormous pressure. There were even thoughts to reduce the power to 400 hp. sec., while leaving the option of "combat" short-term increase to 500 liters. with. However, the military, for obvious reasons, did not understand this idea, and the engineers had to develop a special stamped one-piece aluminum gasket for six cylinders of the block at once. In addition, additional bolts were introduced into the design, tightening the head around the perimeter.
In addition to the fact that the USSR had virtually no experience in the design and construction of "land" high-speed diesel engines, the country did not have a base for the development of fuel pumps. The initial prototypes of the BD-2 (the predecessor of the B-2) had two 6-plunger injection pumps from Bosch with advance couplings. Later, the cams in the pump were modified, bringing them to the shape used in the aviation AN-1. Then the whole structure was redesigned, having already ordered 12-plunger pumps from the Germans. Subsequently, the difficulties with the production of a pump of our own design were overcome, but problems with the quality and volume of production of such a critical unit haunted the B-2 throughout the war.
Despite the difficulties with the revision of the engine, in the pre-war period at the Kharkov plant No. 75, they worked on new modifications of the B-2 line. In particular, an 800-horsepower V-2SN was developed, equipped with supercharging from a drive supercharger. Only a few units of this mighty engine were built, the best of which worked out 190 hours to failure, but consumed too much oil and was clogged with carbon deposits on the piston group. Developed and 6-cylinder "baby" V-3 with a capacity of 250 liters. with. (later it was boosted to 300 hp), which successfully passed first on the Voroshilovets tractor, and later on the BT-5. But even in the 300-horsepower version, this engine was rather weak for tracked vehicles of this class, and they refrained from installing on armored vehicles for some time. It was finalized based on the results of tests and, in the B-4 version, was later installed on the light T-50. Ship modifications V-2 / l (left rotation) and V-2 / p (right rotation) were installed in pairs on light warships of the Navy since 1940.
Tar spoons
The impending war forced the leadership of the Soviet Union to speed up the production of a number of new technology samples, often to the detriment of the quality of workmanship. One can argue for a long time about the advisability of such an approach, but the fact remains - by the beginning of the war, the B-2 was clearly a raw engine that required changes in design. At the same time, without bringing the engine to mind, the plant workers in Kharkov received new tasks, while scattering resources. So, in March 1941, the leadership demanded that the 700-horsepower V-5 for the KV-3 tank be brought to the end and put on the conveyor as soon as possible, and by the fall of the same year, create a giant with 1200 horsepower! Yes, by that time the B-2 was already mass-produced, but it constantly required attention and fine-tuning of production processes. But there was neither time nor resources for this in the Kharkov plant No. 75. We will not dwell in detail on how the history of a tank diesel engine developed after June 22, 1941 (this will be a separate cycle), but we will tell you better about the iconic tests of engines at the Aberdeen Proving Ground in the USA. In the book-monograph by Nikita Melnikov "The tank industry of the USSR during the Great Patriotic War", based on materials from the Russian State Archive of Economics, data are given that characterize B-2 from a not very good side.
Recall that two vehicles, the T-34 and the KV-1, were tested from November 1942 to the end of 1943 by specialists from the Aberdeen Proving Ground. It is worth mentioning right away that the tanks were fired during some of the most difficult periods of our history, and the fact that they appeared at all testifies to the heroism of millions of Soviet citizens. However, dry technical reports from our then allies indicate that one of the B-2's main problems was the air cleaner. I am citing the book of Nikita Nikolayevich Melnikov, Candidate of Historical Sciences, Senior Researcher at the Institute of History and Archeology of the Ural Branch of the Russian Academy of Sciences:
“From the observations made, it is clear that the requirements in our country (that is, the United States) for air cleaners of combat vehicles completely do not allow the use of a Russian-type air cleaner. This was confirmed later, after an engine failure, when there was a lot of dirt inside the engine."
The Americans also pointed out that the filter has high resistance, causing "air hunger" in the motor. Now on the cooling system:
"The cooling of the engine does not meet our standards, and if it were not compensated for by the engine design, the engine life would be significantly reduced."
Obviously, they meant the possibility of a diesel engine to operate at low speeds, which somehow protected the engine from overheating. After that, Nikita Melnikov makes a rather controversial statement that it is for these reasons that the bulk of the successful actions of Soviet tank forces falls on the winter period. Say, the temperatures are lower and there is less dust in the air. The tanks that were sent to the United States were assembled under special control, and even in this case, the T-34 failed due to engine breakdown already at the 73rd hour of the test run. One can only guess at what kilometer an ordinary serial tank would stand in the hands of the American military.
However, there is another point of view on these tests, expressed by Yuri Pasholok, a well-known expert in the field of tank history. He claims that there was no special assembly of tanks, and the Americans simply did not fill the Pomon filter with oil, which is why, in fact, all the troubles happened. If the Yankees had guessed to fill in oil, and even clean the filter in time, then at least they would have achieved 79% air purification. And since 1942, more advanced Cyclone filters have already been installed on the T-34, providing 99.4% of air purification, of course, in a working condition. Only Yuri operates with reports from the archives of the Central AMO of the Russian Federation, and not with materials from the Russian State Archive of Economics, as was the case in the case of Nikita Melnikov. In any case, it's up to you to decide which side you are on in this story.
