The maximum depth reached in a well.

A working shift for drilling crew or other oilfield workers. The most common tour is 8 hours; the three daily tours are called daylight, evening (or […]

The gear or chain arrangement by which power is transmitted from the prime mover to the drawworks, mud pump, or rotary table of a drilling rig.

Are related terms for expressing the same basic idea. The difference between input horsepower and output horsepower is transmission loss. It may be stated as so […]