FIELD: production of sheets of oriented acrylic plastic. SUBSTANCE: device for biaxial stretching of thermoplastic material sheets has stretching units mounted over edges of frame uniformly spaced. Stretching units have clamps consisting of body with projecting front area, bell-crank and two coaxial jaws; lower jaw attached to body projecting area, and upper jaw secured to end of bell-crank hinged to clamp body. EFFECT: improved mechanical and physical service properties. 2 dwg, 1 tbl
