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CHAPTER SEVEN

Gas Drilling Operations

Contents
7.1 Introduction 147
7.2 Gas Drilling Procedures 147
7.2.1 Initiating Gas Drilling 148
7.2.2 Initiating Mist Drilling 148
7.2.3 Making Connections 149
7.2.4 Tripping Pipe 149
7.3 Problems and Solutions 150
7.3.1 Borehole Instability 150
7.3.2 Mud Rings 151
7.3.3 Water Removal 153
7.3.4 Bit Balling 156
7.3.5 Problems Associated with Sonic Flow at the Bit 157
7.3.6 Corrosion 160
7.3.7 Safety 161
Summary 163

7.1 INTRODUCTION
Gas drilling uses air, nitrogen, or natural gas to drill relatively hard
and dry formation intervals. A small amount of water with surfactants
is sometimes added to the gas stream to reduce drilling problems. This
chapter introduces operating procedures in gas drilling to reduce operation
complications and addresses measures that are usually taken to solve gas
drilling problems.

7.2 GAS DRILLING PROCEDURES
Special procedures are followed in gas drilling to ensure smooth
operations. These include initiating gas drilling, initiating mist drilling,
making connections, and tripping pipe.

Applied Drilling Circulation Systems. DOI: 10.1016/B978-0-12-381957-4.00007-3
© 2011 Elsevier Inc. All rights reserved. 147