When the early expansion cone is used to expand solid expandable tubular, the great axial force will be needed and the length of the tube will be reduced considerably.

The Hydraulic force acted on the expansion cone is defined and analyzed; in vertical and horizontal wells, the mechanical behaviors and movements of the expansion tools are researched respectively.

Through optimizing these parameters,the friction between the inner wall and the head of the cone could be decreased,thus optimizing the structure of the expansion cone,which can provide the theoretical basis for the oilfield apply.

Tests on swelling deformation of expansive soils;

Effect of swelling deformation on stability of expansive soil slope

This paper founds the relation of porosity, permeability and swelling deformation under considering swelling deformation made by coal adsorption gas, and by analysis it can be concluded that as gas stress in the coal bed increases, the swelling deformation becomes bigger, the porosity being much smaller, so as to weaken the permeability of the coal bed and make it difficult for gas flow.