Abstract: Low-pressure rotor is a key component of pressurized-water reactor (PWR). Flat anvil and method free from Mannesmann effect (FM) are commonly used in chamfering process of forging nuclear turbine low-pressure rotor. It causes the strain of billet to concentrate on surface areas and wastes the heavy reduction of chamfering process. Process improvement using V-shaped anvil in chamfering process to improve the internal quality of heavy forgings is brought forward and the stress and strain distribution are investigated by means of the combination of physical and numerical simulations. Results show that the contact between V-shaped anvil and forging can increase the hard deformation area of forging surface. So using V-shaped anvil, especially with low angle, in the chamfering process can increase the deformation at the center of the billet and improve the stress state of the center part. Rational staggering anvil process can reduce hard deformation area at the center of the billet during chamfering. It is suggested to use V-shaped anvil in chamfering process with angle of anvil below 120°, reduction above 20% and rational staggering anvil process.

Key words: Numerical simulation, Forging process, Heavy forging, Physical simulation, V shaped anvil