Strategic tractor
At present, as you know, the Minsk Automobile Plant is not engaged in the development of heavy small-scale equipment. For a very long time, this line was given to the Minsk Wheel Tractor Plant (MZKT). But initially, it was at MAZ that the decree of the Council of Ministers of the USSR of June 25, 1954 "On the creation of production facilities and on the provision of the USSR Ministry of Defense with artillery tractors" came. Initially, the army needed precisely wheeled artillery tractors. It was only later that the Minsk heroes mastered the professions of missile carriers and tank carriers. A month later, on July 23, 1954, a secret order # 15ss was issued on the creation of a special unit of the special design bureau SKB-1. It is this bureau that will become the basis for the birth of the modern Minsk Wheel Tractor Plant in the future. The head of the new department is Boris Lvovich Shaposhnik, an experienced automobile designer, who until that moment had worked as a chief designer at the ZIS (since 1938) and at the UAZ (since 1942). At the time of his appointment, Shaposhnik was working on projects for the Mazovian 25-ton dump truck and a 140-horsepower tractor.
Separately, it should be said that in 1954 the Minsk Automobile Plant was the youngest enterprise in the industry: the order to organize car assembly production appeared on August 9, 1944. And after only 10 years, the plant workers are already receiving a serious order for strategic equipment. At the same time, SKB-1 received as a task from the main customer not only the development of a four-axle all-wheel drive vehicle, but also a range of semi-trailers and trailers for its own projected equipment.
MAZ-535 was not the firstborn of SKB-1. Engineers under the leadership of Boris Shaposhnik preliminarily got their hands on the MAZ-529 uniaxial tractor and MAZ-528 biaxial tractor. And after that, ballast tractors MAZ-535 appeared for towing systems weighing up to 10 tons and MAZ-536 for towing 15-ton trailers and semi-trailers. The latter had the status of an experienced one and was made in a single copy. The program of the 536th vehicle was later transferred to the ROC for the development of the MAZ-537 truck tractor and the MAZ-5447 semi-trailer for transporting tanks.
MAZ-535, developed as a heavy artillery tractor with the 8x8 formula, was for its time a truly revolutionary vehicle, far ahead of the serial Western technology. The transmission of its own design was unique, which included an integrated single-stage torque converter, a planetary three-stage gearbox, a two-stage transfer case, interaxle and cross-axle self-locking differentials and planetary wheel gearboxes. In total, the car had 16 driveshafts.
The torque converter is the main highlight of the ballast tractor. It provides a smooth change in torque depending on road conditions without interrupting the flow of power to the wheels, and also allows you to smooth out shock to the motor. A central (more precisely, it would be called an intercarriage) differential with a forced locking was built into the transfer case. The power plant of the machine is a V-shaped 12-cylinder diesel D-12-375 from the Barnaul plant "Transmash" with a capacity of 375 hp. and a working volume of 38, 88 liters. Naturally, such a large diesel engine at that time in the USSR could have one origin - from the legendary tank B-2. The other units of the Belarusian hero were also advanced: the front two axles suspensions were independent, lever-torsion-type with hydraulic shock absorbers (the rear two axles were with dependent balancing unsprung suspension), the front two axles were controlled with a hydraulic booster. When the 535A version appeared, one of its innovations was the independent suspension of all wheels. Initially, MAZ-535 received all single wheels, chamber tires with dimensions of 18.00-24 and, of course, with a centralized pressure control system from 0.7 to 2.0 kgf / cm3… The central valve of the pumping system was located in the cab, and on the outside on the frame there were individual wheel cranes to disconnect the damaged tires from the main system. The MAZ-535 frame had an original trough-like shape with built-in spars. It should be noted that similar developments on heavy wheeled vehicles were carried out in the SKB of the Likhachev plant, but the Minsk vehicles were distinguished by a more thought-out design. Why? Unlike the four-axle ZIL-135 (it appeared a little later than the 535th car), one diesel engine and a hydromechanical automatic was installed in Minsk on the tractor, which saved the car from the difficulties with setting up a twin-engine transmission.
The MAZ-535 did not have an abstruse system with controlled front and rear wheels, which Muscovites put on the 135th car. This, of course, allowed the four-axle ZIL to turn almost on the spot, and also created only four tracks when turning in the snow, but required a complex system of long steering rods going through the entire body. In general, in the case of ZIL-135 and MAZ-535, an interesting contrast emerged between typical representatives of two independent schools of heavy equipment design, headed by V. A. Grachev and B. L. Shaposhnik, respectively. In Moscow, they chose the idea of on-board transmissions and the power plant of their two ZIL-375 engines with a capacity of 180 liters each. with. Each, through a five-speed transmission, drove four wheels of its side. With this design, Grachev allowed himself to abandon differentials, their locking mechanisms, additional gearboxes and a transfer case, which somewhat increased the overall efficiency of the truck. In addition, the number of cardan shafts in the ZIL-135 was only eight, in contrast to the Mazovian 16 pieces. The general simplification of the ZIL design made it possible to seriously lighten the eight-wheeled vehicle. However, in the end, the concept incorporated in MAZ-535 is still alive, but Zilov's developments have sunk into oblivion.
Machine for unambiguous use
Naturally, they could not create such a complex car practically from scratch in Minsk: at that time, the Soviet Union did not even have the initial experience in designing such high-tech wheeled vehicles. Despite the fact that Minsk never spoke and does not talk about foreign prototypes, certain borrowings in the work of SKB-1 engineers did exist.
It is clear that MAZ studied the heavy four-axle Schwerer Panzerspähwagen Sd. Kfz.234 ARK (from the German Achtradkraftwagen - eight-wheeled vehicle), developed by Büssing-NAG - after all, it was the world's first 8x8 armored personnel carrier.
Yevgeny Kochnev writes in his book "Secret Cars of the Soviet Army" that Minskers took the idea of installing a 12-cylinder diesel engine from a German car. The Sd. Kfz.234 was powered by a Tatra-103 engine with a working volume of 14.8 liters and a capacity of 210 liters. with. In addition, by analogy with the Germans, self-locking differentials and individual independent suspensions were installed on the MAZ-535.
If we talk about the layout solutions of the Minsk hero, then the transatlantic influence is clearly visible here. In the early 50s, the T57 and T-58 vehicles appeared in the Detroi arsenal, which are artillery tractors for 10 and 15 tons. These were experimental 8x8 vehicles with a cab with a flat front panel, three frontal headlights and a soft top brought forward to a short front overhang of the frame. The engine compartment was located behind the cockpit above the four front steerable wheels. Doesn't it look like anything? In the United States, these machines, along with the XM194E3 heavy truck tractor, remained in the category of experimental designs, having no effect on the American automotive industry. But in the USSR, they served as prototypes for a unique family of strategic vehicles. By the way, the Detroit Arsenal itself, with its design, production and testing facilities, largely served as a prototype for a similar domestic facility - the 21st Research Institute of the USSR Ministry of Defense.
Be that as it may, the technical history of any state is filled to the limit with examples of creative rethinking of foreign experience, which saves time and resources. Namely, this was acutely lacking in the country, which had not yet recovered from the consequences of the Great Patriotic War. The very fact of developing and mastering such a high-tech product as the MAZ-535 tractor can already be ranked as heroic.
You can learn how the MAZ-535 was an unusual machine not only for ordinary people, but also for testers, in the book "50 years on the march", dedicated to the anniversary of the institute in Bronnitsy near Moscow. Now it is the 21st Research and Testing Institute of the Main Armored Directorate of the Ministry of Defense of the Russian Federation mentioned above. The test driver recalls on the pages of the anniversary edition:
“Multi-axle heavy vehicles of the Minsk Automobile Plant passed through our 13th department. The first vehicle was the MAZ-535 four-axle chassis. At first it was scary to sit down for him. Huge size, powerful engine. And also an unusual control. Still: there is no clutch pedal, there is no gear shift lever either. There are only gas and brake pedals. Gradually I got used to it, and over time it became easier to drive Minsk tractors than cars with a clutch pedal and gear levers."
