Page 64 - Drilling Technology in Nontechnical Language

Chapter 3 – DRILLING A LAND EXPLORATION WELL 55

Moving the rig on location and attaching the diverter

Land rigs break down into packages that are moved by truck. To
reassemble the rig on location requires care and precision. Each major
part must be accurately positioned relative to the rig substructure, so that
cables, walkways, pipes, and other equipment line up and can be easily
connected. Each rig has a procedure, outlined in the rig operating manual,

that details what must go where and in what order, for the most efficient
assembling of the rig.
The rig substructure is constructed from steel beams welded together.

The substructure is a large frame that supports the drill floor, generally
about 15 ft to 20 ft (4.6 m to 6 m) above ground level, and the derrick (less
commonly called the mast). The substructure itself may split into several

smaller packages for transport. In the middle of the drill floor is a hole,
inside of which is a powered turntable. This is called the rotary table and
is used to turn the drillstring for drilling, as well as for other tasks.
Once the substructure is placed in the correct location, the derrick is
laid out onto cradles and assembled (fig. 3–10). The cradles position the

mast so that it can be attached to the substructure above the drill floor.
At the substructure end, the derrick is secured by large steel pins, several
inches in diameter, to allow the derrick to pivot to the upright position.
When everything is ready, the derrick is rotated to vertical by winching in
on steel cable attached to the derrick, and the remaining legs are pinned
in place onto the rig substructure. With the derrick upright, rigging up
continues until the rig is ready to start drilling.

Fig. 3–10. Assembling the rig on location

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