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powershift transmission (automatic). These engines are diesel fueled and are rated between 425-550
hp. The power is used primarily to turn the drill string and raise and lower equipment in the well.
Engines also supply the electricity used on and around the rig. Electrical power is supplied,
usually, through two generator sets. The rig can run with one of these units but it would run at close
to maximum output at night. The second provides for back-up, and allows for other options. These
engines are generally rated at 300-350 hp. They are housed on a skid and are enclosed; this unit is
referred to as a "light plant".
Rigs also employ 1 or 2 engines to power the mud pump. Total output varies from 300-
500hp. When two engines are used they must be tuned to match and are hooked together through a
gear box. One of these engines runs clockwise while the other runs counter-clockwise. Power for
most these application is through a clutch with an over centre release mechanism - they can be
locked in the released or engaged position.
The hoisting system is used to raise and lower and to suspend equipment in the well. The
drilling line (wire rope) is usually braided steel cable about 1 1/8 inches in diameter. It is wound
around a reel in the draw works. The engines are connected to the draw works and let the drilling
line in or out. The derrick or mast is the steel tower. If the tower comes on a tractor-trailer and is
jacked up, it is a mast. If the tower is erected on the site, it is a derrick. The drilling line goes over a
pulley, called the crown block, at the top of the derrick, and then down to another pulley called the
traveling block. Below the traveling block is a hook to which equipment can be attached. As the
drilling line is reeled in or out of the draw works, the traveling block rises and falls in the derrick.
This raises and lowers the equipment in the well.

Speaking section

12 Make up a dialogue on the following situation and talk to your friend. Let one of your group
mates translate the dialogue consecutively.
You have a talk with the offshore driller. Ask him about the peculiarities of working in a
marine environment.

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