By the method of freeze-gel casting,with inducement of temperature gradient,a solid loading of 20vol% slurry constituted of tert-butyl alcohol,acrylamide and alumina powder was used to fabricate porous alumina ceramics green bodies with directional pore channels structure.

The freeze-casted green body under controlled temperature distribution contains oriented and aligned pores, which favours fabrication of porous ceramics and has drawn much attention of researchers.

Hydraulic jetting oriented perforating and fracturing in horizontal well;

Based on analysis the mechanism about declining deformation fracturing pressure,and carried on comparison studies about perforating technology between oriented perforating and compound perforating.

Study on initiation and propagation mechanism of fractures in oriented perforation of new wells;

Research on oriented perforation optimization technique for fracturing wells in tight gas reservoir;

Combining the characteristics of oriented perforation,geological feature analysis of fracture reservoirs,sand production reservoirs,fractured reservoirs and waterflooded reservoirs shows that oriented perforation is more suitable in these reservoirs than conventional perforation.

The system is constructed by drilling method and the air intake and the gas outlet are connected by a directional drilling hole.

As a trenchless construction method, directional drilling and PE pipe dragging is uniquely advantageous, with less impact on nearby buildings and traffic, lower cost for maintenance, better protection of the ground services, etc.

Spiral and round curve methods of General Geological Coordinate System have established the basis on which the design of curved or directional drilling can be well calculated .