Page 149 - 4714

members put the rig together, or rig up. After they drill the well, they
dismantle the rig, or rig down.
As mentioned earlier, in deserts and other flat places, the
contractor may skid the rig. A rig suitable for skidding has enormous
wheels attached to the substructure, which, when engaged, allow the
rig to be towed short distances without a crew's having to dismantle it.

Moving and Setting Up Offshore Rigs
Some offshore rigs are self-propelled. Built-in engines and
screws (propellers) move the rig through the water. Rudders like those
on a ship allow marine personnel to steer the rig when it is underway.
While a self-propelled rig’s speed is slow – perhaps 3 or 4 knots per
hour at the fastest – generally, the distances traveled are relatively
short, so speed is not a factor. For rigs that are not self-propelled, the
contractor can hire boats to tow them.

For long moves, say from one ocean to another, the contractor
may use a special ship to carry the rig, whether it is self-propelled or
not. To load the rig onto the ship crew members moor the ship next to
the rig, usually in the shallow waters of a port. At first, both the boat
and the rig float. They then flood compartments in the ship to
submerge its deck below the waterline. With the deck below the
water's surface, large cranes pull the rig over to the ship’s deck.
Pumps remove the water from the compartments and the ship floats
back to the water’s surface with the rig in place on the deck.
Whether on land or offshore, once the site is prepared for the
rig, the next step is for the drilling crew to rig up – that is, to put the
rig components together and prepare the rig for drilling. So, let’s look
next at rigging up.

5 Find synonyms in the text for the following words.

swamp spot
personnel pebble

148