The invention relates to a
hexahedron finite element grid partitioning method for simulating screw-thread fit. The method comprises the following steps: firstly, according to a distance change rule ofa thread surface and a thread axis, determining a single-layer thread cross section
contour line, and using a minimum feature of a thread as the axial
finite element grid size; and according to a rotation angle relation between the number of the grid
layers axially partitioned within a single thread
pitch and the adjacent layer, determining the circumferential
finite element grid number, throughthe
quadrilateral grid stretching of the bolt thread end face, forming a single-layer hexahedral grid, and performing the copy, the rotation and the node replacement on the single-layer hexahedral grid so as to obtain a single-
pitch bolt hexahedral grid model; finally, according to the male-female thread
tooth number, performing the copy and the translation on the single-
pitch grid so as to obtaina hexahedral grid model of the whole bolt thread part. So, the
hexahedron finite element grid partitioning method does not need to build a
solid three-dimensional model of a male-female thread, and does not need a lot of the node coordinate calculation.