Prestress open type straightener rack

The invention belongs to the technical field of straightening equipment, and relates to a prestress open type straightening machine rack which comprises an upper rack and a lower rack, one side of the upper rack is hinged to one side of the lower rack through a rotary unit, and rotary locking oil cylinders are longitudinally and symmetrically arranged on the other side of the lower rack front and back; an opening oil cylinder is arranged on the side close to the rotation unit, a cylinder barrel of the opening oil cylinder is installed on the outer side of the lower rack in a hinged mode, and a first piston rod of the opening oil cylinder is hinged to the bottom of the upper rack. A locking oil cylinder and an opening oil cylinder are rotated to jointly apply force, so that the opening type rack forms a prestress frame structure, and the working process is more stable and reliable; meanwhile, according to the prestress open type straightening machine frame, the upper machine frame and the lower machine frame a