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The skid-beam trailer for Rigs 155 and 158 have eight tires
each, measuring 40-in. wide by 10 ft tall. A single tire costs
$30,000 . Rig 102 has the same type of system, but smaller tires,
measuring 36 in. by 8 ft tall. “The skid-beam system saves 4-5
days in moving," Howe said.

Telescoping derrick

The telescoping derrick, a single-trailer system (Fig. 3), is
employed on the remainder of Santa Fe's three rigs in the Wafrah
(PNZ) and Umm Gudair fields (southern Kuwait). According to
Vinot Desai, manager of engineering for Dreco Inc., "these rigs are
specifically designed to move fast."
Rigging down consists of scoping the upper section of the
mast (crown section) down into the base section by means of a
wire line reaving system and hydraulic winch. Once the top section
is inside the base, two hydraulic cylinders lay the whole derrick
over onto the headache rack.
Next, the subbase jacks are used to jack up the substructure
which is then pinned into the traveling position. Once pinned, the
jacks are retracted and the front end is hooked onto the fifth wheel
prime mover.

Moving efficiencies

Through the use of these mobile desert-drilling rigs, Santa Fe
has attained exceptional cost savings by improving moving
efficiencies. For example, from 1995 to 1997, Rig 8 improved its
moving time by 20 hr (integral wheel), Rig 20 by 14 hr (skid
beam), and Rig 1 by 8 hr (telescoping derrick), all within a
distance of 30 km.
The newer integral wheel and skid-beam systems provided
higher incremental improvements in moving efficiency achieved
through the learning curve. The telescoping derrick is a much older

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