FIELD: forging. SUBSTANCE: technique implies two working regimens: rough and finishing treatment. The first regimen means long and low frequent strokes of block heads; the second means short and high frequent strokes of block heads. The hydraulic machine in question is provided with mechanisms to control the length of strokes of the block heads. Each mechanism is made like a pump with adjustable volume of its working chamber. The volume adjusting device has at least one additional piston located in the chamber and engaged with its main piston. There is an additional chamber coaxial to the main one. EFFECT: higher efficiency and reliability. 3 cl, 3 cl, 3 dwg
