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PART TWO

Gas Drilling Systems

Different types of gases are used as drilling fluids to drill geotechnical
boreholes, mining boreholes, oil and gas recovery wells, and water wells.
Since gases have considerably lower densities than water, they are used
for drilling relatively dry rock formations that do not produce a signifi-
cant amount of liquids during drilling. The main purpose of gas drilling is
to improve drilling performance by increasing the rate of penetration in
hard formations.
This part of the book provides drilling engineers with basic informa-
tion about gas drilling systems and techniques that are used to reduce the
risks associated with gas drilling to safely achieve the best drilling perfor-
mance. This part consists of three chapters:
Chapter 5: Equipment in Gas Drilling Systems
Chapter 6: Gas Compressors
Chapter 7: Safe Gas Drilling Operations

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