Yielding Rules of Materials in Ring Die Pellet Mill

Yielding rule is also called shaping condition, which is the standard to judge the stage that raw materials of ring die pellet mill are in. If stress is smaller than the yielding point, raw materials are in elastic state. But, if stress is larger than the yielding point, raw materials enter into the plastic state from elastic state. The above situations will occur if stress is in one-way.

If stress is complex, materials will enter into the plastic state as long as the stress meets certain demands. This is the yielding principle that is under complex stress, which is often called shaping condition. The key to plastic deformation is how to select and set up the yielding rule during the working process of ring die pellet mill.

In this paper, we can make the following assumptions when setting up yielding principle. At first, we can take the biomass materials as compressible continuum. Secondly, hydrostatic pressure is on yielding surface. The frequently-used yield rules conclude Tresca, Mises, Drucker-prager, Mohr Coulomb, etc.

Through the study on plastic deformation, we introduce the three rules: yielding rule, hardening rule and flowing rule. Meanwhile, we adopt the eulerian method to study the finite deformation. According to the influence of hydrostatic pressure and yielding situation, we deduce the elastoplastic constitutive equations.

Meanwhile, judging by the features of plane strain, we set up the constitutive equations. Leave your email on website to get the price list and PDF of ring die pellet machine!