A data structure of B-Rep model-based 3D solid is introduced in this paper.

Based on the optizum design of the loader s working device, discussed the 3D solid design of the working device.

So the constrained Delaunay triangulation method can be applied to generate mesh on any complex convex and concave 3D solids.

The second use of the 3d model created in 3d mechanical designing;

A transfer methodology from 3D model to 2D mask layout in MEMS CAD field was put forward after studied respectively the format of the standard 3D model file and the 2D mask layout file.

For the question of fusing display of circular area on 3D model, a simple solution was put out, that used a spot light source to simulate the fusing effect of circular area display on 3D model.

CAD three dimensional entity assistance teaching method in "Mechanical drawing" in teaching application;

Founds the three dimensional entity based on the AutoCAD the two-dimensional graph and the size marking layout;

The relationship between an object s three dimensional entity and its two-dimensional multi-views can be expressed vividly and visually by Solid Edge V11 parametric molding software, which constructs three-dimensional entity model and represents an engineering object spatially and dynamically.