Modified model of calculating minimum flow in air drilling;

Application of PDC bits in air drilling of Puguang-10 well;

The influence and countermeasure of air drilling technology on geologging work;

Quantitative analysis and controlling method for pipe string erosion in gas drilling;

Development and application of drill pipe valve used in gas drilling;

Causes of and solutions to easy deviation of gas drilling track;

Calculation of optimal gas-liquid volume flow in aerated drilling

In order to tackle the difficulties like hole inclination in cretaceous nappe, light weight on bit as well as slow penetration, and the issue of increasing velocity of the Tertiary in Qinxi oilfield, aerated drilling testing was conducted in the nappe of well Ku 12 and in the Tertiary formation in well Q2-37.

Based on the theory of gas-liquid two-phase flow,the wellbore pressure distribution problems were analyzed in the aerated drilling.

Selection of oil & gas drilling core Technology is very important to scientifically and reasonably lay down scientific-technical development strategy in oil & gas drilling.

A debris-gas sample collecting device for air drilling;

But on the other hand, air drilling adopted air as the circular medium and so hydrocarbons like natural gas and oil mixed with air will cause downhole explosion if only the mixture reaches the explosion limit under any possible explosive condition, which will certainly threaten the safety during operations of air drilling.

The advantages of air drilling,such as much faster in footage,protect the reservoir from contamination and less cost, make its widely application in oil fields, whereas the pressure distribution in circulation,the drilling machinery choice and the configuration of drilling parameters is distingu.