In 2025, an Indonesian EPC contractor building a coal-fired power plant in East Java needed five pumps to transfer concentrated sodium hydroxide (NaOH) from a storage tank to the boiler house — approximately 1,000 meters away. These pumps would serve the boiler feedwater pH control system, where reliable NaOH dosing is critical to prevent acidic corrosion and protect the steam generation equipment.
The Challenge
Three pump technologies were evaluated and two were rejected:
Centrifugal pumpswere ruled out for their high rotational speed (1,450–2,900 RPM), which increases mechanical seal failure risk when handling hazardous chemicals. Their flow rate also varies with system backpressure, compromising dosing accuracy over a long pipeline without additional control equipment.
Gear pumpswere eliminated due to inherent design limitations. Gear pumps rely on metal-to-metal contact between meshing rotors, which accelerates wear dramatically in low-viscosity fluids like NaOH (44 cP) that provide insufficient lubrication. Frequent seal replacements, pronounced flow pulsation requiring dampeners, and the need for full disassembly during maintenance — typically 4–6 hours per repair — made them unsuitable for this continuous-duty application.
Why Bonve Rotary Lobe Pumps Win Over Gear Pumps
Bonve's non-contacting rotor design fundamentally avoids the failure mechanisms that plague gear pumps. With precision clearances between rotors rather than metal-to-metal mesh, there is virtually no mechanical wear under normal operation. This single difference cascades into multiple advantages: the double mechanical seal operates in a stable environment free from dynamic load fluctuations, maintenance is reduced to front-cover access without removing the pump from pipework (under 2 hours vs. 4–6 hours for gear pumps), and the Tri-lobe rotor delivers inherently low-pulsation flow — eliminating the need for pulsation dampeners. In NaOH service, where gear pumps typically require major overhaul within 1–2 years, Bonve lobe pumps are designed for 5+ years of continuous duty.
The Solution
After evaluating multiple manufacturers, the EPC contractor selected the Bonve rotary lobe pump model 65BV12-10. Five units were supplied with the following configuration:
- Medium:48-50% NaOH
- PH:14
- Viscosity: 44 cP
- Temperature: Ambient temperature
- Flow rate: 5 m³/h
- Pressure: 10 bar
- Pump Technical datasheet
- Model: 65BV12-10
- Rotor type: Tri-lobe rotors
- Material: SS316L
- Seal: Double mechanical seal
- Motor power: 5.5 kW
- Anexternal pressure relief valveprotects the discharge pipeline from overpressure.
Results
The 5 sets pumps were commissioned in October 2025 and have operated continuously since. After eight months of 24/7 NaOH transfer duty:zero unplanned downtime, zero mechanical seal leakage across all five units, and only scheduled barrier fluid top-ups required— no unplanned maintenance of any kind.
Conclusion
This installation validates Bonve's core engineering advantages for aggressive chemical service: non-contacting rotors eliminate the wear-driven failures of gear pumps, SS316L metallurgy with double mechanical seal provides multi-layer containment, and the positive displacement design maintains rated flow regardless of pipeline distance. 5 sets pumps, eight months, zero failures.
For caustic soda and other challenging chemical transfer applications, contact Bonve Pumps to discuss your requirements.
For more details please contact me:
Andre Chen
Sales Engineer
Mobile/WhatsApp/Wechat: +86 15888591452
Email: bvsales2@bonvepumps.com
