Electric generators powered by large diesel engines (the prime movers) generate electricity that move the heavy rig equipment such as the rotary table (or top drive), mud pumps and drawworks. Electric drill rigs are more expensive than mechanical rigs, but offer some nice advantages in return.
[pdf] Core drilling is a method of drilling that involves using a special drill bit and drill to remove a cylindrical core of material. This technique is often used in construction and other industries to create holes.
[pdf] With interchangeable core bits capable of drilling holes from 1.5" to 9" in diameter, operators can tackle diverse pipe materials including vitrified clay, concrete, ductile iron, cast iron, C-900, HOBAS, and PVC/HDPE systems using a single versatile machine.
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