What are the most common types of mud pumps?

• A. Impulse, piston, and rotor pumps
• B. Rotary, diagonal, and vane pumps
• C. Duplex, triplex, and centrifugal pumps
• D. Gear, screw, and peristaltic pumps

Answer: (C)

Mud pumps in rotary drilling are the workhorses that push drilling mud down the string and back up, and the most common configurations you’ll encounter are duplex and triplex piston pumps, along with centrifugal pumps. The duplex (two plungers) and triplex (three plungers) are positive-displacement pumps that generate the high pressures needed to force mud down the drill string and through the bit, which helps keep the borehole clean and the bit cooling. Centrifugal pumps, on the other hand, deliver higher flow at lower pressure and are often used to provide ample circulating volume or to supplement the system when high pressure isn’t required. Together, these three types cover the typical mud-pumping setups on many rigs.

Other groupings include pump families that aren’t standard mud pumps in this drilling context, such as rotor or vane-based types or gear, screw, and peristaltic pumps, which aren’t the primary high-pressure mud pumps used in rotary drilling.