Study on the Deformation of the Prestress Frame of Open-Die Forging Hydraulic Press with Different Operating Modes

Abstract

The deformation of the prestress frame of open-die forging hydraulic press is studied in the paper. Firstly, the computing formula of true prestressing force of frame is deduced, and then the finite element model of prestress frame is established. With the model, the deformation of prestress frame is studied when the press works under different operating modes including upsetting, elongating and saddle forging and the effect of different operating modes on the deformation are revealed. The main achievements include: The true prestressing force of frame can be gained with nominal prestressing force, section area and working length of tension rods, section area and length of columns. Under prestress, the stress of the field of up beam and down beam acted by the axial force of tension rods and columns is bigger, that of the other field is very small. Under working loads, up beam and down beam tend to open out, tension rods and columns tend to bend in, and the bending effect cause the stress of inner field of tension rods bigger than that of outer field and the stress of inner field of columns smaller than that of outer field. The deformation of down beam under saddle forging is different with that under upsetting and elongating. The stress of center field of down beam under upsetting and elongating is higher and that of front and back field of down beam under upsetting is higher. The main achievements of the study are useful to design the prestress frame of open-die forging hydraulic press and the research method can be used to study the prestress frame of other equipments.