Page 25 - Air and gas Drilling Field Guide 3rd Edition

16 CHAPTER 2 Air and Gas Versus Mud

concept allows rapid rig-up and rig-down, which minimizes nondrilling time at the
location. These rigs have been developed by Helmerick and Payne Incorporated, an
international drilling contractor serving both on-land and off-shore drilling opera-
tions. These rigs are available in depth capabilities up to 18 000 ft (5500 m).

2.2 CIRCULATION SYSTEMS
Two types of circulation techniques can be used for either a mud drilling system
or an air or gas drilling system. These are direct (conventional) circulation and
reverse circulation.

2.2.1 Direct Circulation
Figure 2-6 shows a schematic of a rotary drilling, direct circulation mud system that
would be used on a typical double (and triple) drilling rig. Direct circulation
requires that the drilling mud (or treated water) flows from the slush pump

ROTARY HOSE
STANDPIPE
SWIVEL SLUSH
KELLY PUMP

MUD LINE

MUD TANKS
DRILL PIPE
SHALE SHAKER

DRILL COLLAR

BIT

FIGURE 2-6. Direct circulation mud system.