| 1 | Hydraulic suitability | Compare rated flow, total dynamic head, suction lift, solids-handling capability, discharge size, and duty cycle. | Select a pump whose certified performance curve meets the required duty point. Allow a reasonable operating margin, but avoid excessive oversizing. | A pump that cannot meet the duty point may cause flooding, while an oversized pump can increase fuel use, wear, and purchase cost. | 25% |
| 2 | Supplier technical capability | Review engineering drawings, performance curves, material specifications, factory testing, documentation, and commissioning assistance. | Require a written quotation stating flow, head, engine rating, fuel tank capacity, maximum solids size, priming method, and operating limits. | Clear technical documentation reduces the risk of receiving equipment that is difficult to install or unsuitable for actual sewage conditions. | 15% |
| 3 | Maintenance support | Compare preventive-maintenance schedules, service procedures, troubleshooting guides, training, field support, and spare-parts availability. | Confirm access to routine service parts such as oil filters, fuel filters, air filters, belts, mechanical seals, gaskets, and impeller components. | Regular engine and pump maintenance helps control downtime and protects performance in abrasive or debris-heavy sewage applications. | 15% |
| 4 | Warranty clarity | Check warranty duration, covered components, exclusions, claim process, labor coverage, transport responsibility, and operating-condition requirements. | Obtain warranty terms in writing. Confirm whether the diesel engine, pump end, controls, battery, and fuel system have separate coverage conditions. | A longer warranty is not automatically better if exclusions are broad or the claim process is unclear. | 10% |
| 5 | Fuel and operating efficiency | Compare fuel consumption at the actual duty point, engine loading, tank capacity, noise, exhaust requirements, and expected annual operating hours. | Use supplier test data or engine fuel curves at the intended load; do not compare fuel figures measured at different flow and head conditions. | For frequently operated pumps, fuel can become one of the largest ownership costs and may exceed the initial price difference. | 15% |
| 6 | Total ownership cost | Include purchase price, freight, installation, fuel, lubricants, routine service, spare parts, labor, repairs, disposal, and expected downtime. | Use a multi-year estimate: TCO = purchase and installation + fuel + maintenance + repairs + downtime-related costs − residual value. | The lowest quotation may not be the lowest-cost option if it consumes more fuel or requires longer service interruptions. | 15% |
| 7 | Reliability and safety | Assess automatic priming, dry-run protection, low-oil shutdown, high-temperature protection, emergency stop, guarding, lifting points, and enclosure quality. | Request documented protection features and verify that the package complies with applicable local electrical, emissions, lifting, noise, and workplace-safety requirements. | Protective systems reduce avoidable damage and improve operator safety, especially at unattended or remote sewage stations. | 5% |