Wegener also noted that the continents move up and down to maintain equilibrium in a process called isostasy. As an example he cited the sinking of Northern Hemisphere lands under the weight of continental ice sheets in the last ice age, and their rise since the ice melted some 10,000 years ago.
Drill that is fitted with a Pipe provides effective connection to the rig surface equipment or application with the bit and the bottom hole assembly for the purpose of pumping the Drill fluid to the bit.
Drilling vs Boring. Drilling and boring are two methods of machining used in manufacturing. Both methods are used for creating or enlarging a circular hole in the material. More about Drilling. Drilling is the cutting process of a material using a specially designed rotating cutting tool called a drill bit.