Page 120 - Drilling Technology in Nontechnical Language

Chapter 5 – RIG SELECTION AND RIG EQUIPMENT 111

powder, and mud chemicals. The rig systems have to be able to transfer
and mix these to produce the required cements and drilling fluids. The rig

is transported by a fleet of trucks to the required location.
A heavy land rig typically costs around $80,000 a day.

Fig. 5–2. Land rig in the desert
Photo courtesy of Schlumberger.

Light land rig

A light land rig will be suitable for drilling shallower wells. It might
also be used for working over an existing well that requires major repair or
replacement of the completion. In this case the old completion is removed
from the well and a new completion is run.
It will most likely have two high-pressure pumps for circulating drilling
fluid around. Capacities in general will be lower than for a heavy land rig.

The rig is transported by a fleet of trucks to the required location.

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