Abstract: The rubber in a screw-pump’s stator is not only susceptible to damage, but also to affect a screw-pump’s working performance by the conjugate situation between its stator and rotor. Recently, the effective method has been not found for testing the deformation and forced state of the rubber of a stator under a real working condition. The deformation principle of an inner contour line of the rubber is studied mainly and its stress and strain state subordinately. For a screw-pump’s working situation, its forced state and deformation principle is researched firstly under an even inner pressure and secondly under a working pressure difference and under different assemble between its stator and rotor. The stress state and deformation principle of a screw-pump’s stator has been obtained by FEM analysis software (ABAQUS) under different working conditions. The stresses and strains of the stator and displacements of its inner-contour line under 3D model and plane strain model is verified to be almost coincident. Therefore, the plane model can replace 3D one and improve analysis efficiency.

Key words: Deformation, FEM, Rubber, Screw-pump, Stator, Glossiness, Micro-topography, Ray tracing, Rolling transfer, Appearance quality