| 1 | Define required flow rate | Planned mud flow, bit hydraulics, hole size, nozzle configuration, and annular velocity. | Select a pump whose usable flow range covers the calculated operating point without running continuously at maximum capacity. | Positive-displacement triplex and quintuplex pumps provide adjustable flow through stroke length and speed changes. | Confirm flow calculations against the bit hydraulics program and the required hole-cleaning velocity. |
| 2 | Calculate discharge pressure | Target total circulating pressure, standpipe pressure, depth, mud weight, rheology, and pressure losses. | Choose a rated pressure above the maximum calculated working pressure, while allowing a suitable operating margin. | Pressure rating must account for fluid-end components, liners, pistons, valves, discharge piping, and relief protection. | Review the pressure rating under the actual liner, piston, stroke, and speed combination—not only the headline rating. |
| 3 | Match the mud properties | Mud density, plastic viscosity, yield point, solids content, temperature, abrasiveness, and chemical composition. | Use fluid-end materials and expendable parts compatible with the planned drilling-fluid system. | Abrasive or high-solids mud can accelerate wear on liners, pistons, valves, seats, and internal passages. | Obtain material compatibility data and check expected service life under the actual mud formulation. |
| 4 | Evaluate duty cycle and reliability | Operating hours, expected load profile, continuous or intermittent service, redundancy, and maintenance intervals. | For continuous drilling, avoid sizing the pump only for short-term peak performance; consider reserve capacity or standby equipment. | Quintuplex designs can reduce discharge pulsation and may support smoother operation at comparable flow requirements. | Check crankcase design, lubrication, bearing loads, vibration control, inspection access, and planned spare-parts inventory. |
| 5 | Check power and drive compatibility | Available prime-mover power, transmission type, operating speed, efficiency, fuel or electrical supply, and installation constraints. | Confirm that the drive can deliver the required hydraulic power at the intended pump speed with reasonable reserve. | Hydraulic power is approximately calculated as pressure multiplied by flow; actual input power is higher because of efficiency losses. | Verify alignment, coupling requirements, control-system integration, available footprint, weight limits, and lifting provisions. |
| 6 | Plan for pulsation and pressure control | Allowable pressure fluctuation, measurement accuracy, standpipe-manifold layout, and equipment sensitivity. | Use a properly sized discharge pulsation dampener and maintain reliable pressure-relief protection. | Pulsation control helps limit vibration and pressure variation in the discharge line, but it does not replace correct pump sizing. | Confirm dampener precharge procedures, relief-valve settings, gauge range, pressure sensors, and discharge-line supports. |
| 7 | Assess operating environment and life-cycle cost | Altitude, ambient temperature, offshore or land installation, noise limits, transport requirements, service access, and maintenance resources. | Compare total ownership cost rather than purchase price alone, including energy use, consumables, downtime, inspections, and repairs. | Harsh environments may require enhanced corrosion protection, enclosure design, cooling capacity, filtration, and remote monitoring. | Review applicable safety requirements, documentation, test records, maintenance procedures, and availability of critical replacement parts. |