Abstract: So far theoretical researches on relationships between the feeding value of the centre roll of the plate bender with three rolls and the curvature of the aircraft hull plate formed have been a little introduced in present reference materials and literature. In this paper, forces and deformations of the aircraft hull plate in the symmetry plate bender with three rolls are systematically analyzed and investigated by means of elasticity-plasticity theory, and a group of theoretical calculation formulas is put forward by which the feeding value and the exerting force of the centre roll may be determined according to the thickness of the hull plate, the elasticity modulus and yield point of the hull plate material, and the curvature which the aircraft hull plate should have after forming.

Key words: exerting force necessary to form the aircraft hull plate, symmetry plate bender with three rolls, elasticity-plasticity bending