Since the advent of landmines before the First World War, the question of how to effectively clear them has remained a principal focus of research for military organizations.
The Soviet Union began systematic research in this field during the 1930s, with the first mine-clearing device, the ST-26, introduced in 1932. The ST-26 was a mine plow mounted on the front of a tank, designed to unearth mines as the vehicle advanced. However, testing demonstrated that its performance in terms of speed and maintenance was unsatisfactory, and the system proved ineffective on hard, muddy, or heavily overgrown terrain.
In parallel, the Soviets experimented with flail mechanisms. In 1934, a flail device was developed for the BT-5 tank, consisting of a rotating steel drum fitted with numerous chains that continuously struck the ground to detonate mines. Yet operational testing revealed two critical shortcomings: the chains often became entangled, and the dust clouds generated by impact severely restricted the crew's visibility. This approach was soon abandoned. Attention then shifted to roller-based methods, leading to the introduction of the CT-26 in 1937. The CT-26 employed heavy rollers mounted at the front of a tank, using their weight to detonate mines by pressure. This system addressed the shortcomings of its predecessors and was considered to hold significant development potential. Nevertheless, none of these devices were formally adopted prior to the outbreak of the Second World War.
When the German Army retreated from Moscow in 1941, it employed minefields to delay Soviet pursuit. This experience again underscored for the Soviets the critical importance of mine-clearing equipment. In response, the PT-34 mine roller, designed for the T-34 tank, was introduced in 1942. Two versions were initially tested: reinforced-concrete rollers and steel rollers. Trials revealed that reinforced-concrete rollers performed poorly in winter conditions and exerted insufficient ground pressure compared with the steel version. The steel roller configuration was therefore adopted and deployed in autumn 1942.
The PT-34 weighed 5,300 kilograms and consisted of ten rollers, each with a diameter of 1,200 millimeters, mounted on a frame measuring 2,870 millimeters in length and 3,820 millimeters in width. The rear of the frame was fixed to the front of the tank, while its forward section carried five rollers on each side. Each roller was fitted with twenty metal studs around its circumference, concentrating pressure on the ground. The rollers were mounted with freedom of vertical and longitudinal movement relative to the frame, enabling them to adapt to uneven terrain, increase the likelihood of detonating mines, and reduce damage from explosions.
By 1943, based on battlefield feedback and with the intention of adapting the system for use across various Soviet tank models, the PT-34 underwent detailed modifications and was redesignated as the PT-3. This version remained in operational service until the end of the Second World War.
The research, development, and operational experience gained through these early efforts exerted a profound influence on the subsequent evolution of mine-clearing technology. Postwar systems such as the Soviet PT-54, KMT-5M, and KMT-7, as well as the American Track-Width, Tank-Mounted Mine Roller (employed on the M60A3 Panther and M1 Panther II), all reflected the design legacy of the PT-3.