(Bonve Cam-Type Twin Rotor Pumps)

1.Flow Rate(Q)-Direct Reflection of Process Demand

Volume of liquid delivered by the pump per unit time.Unit:m³/h.

Selection Key:Determine the rated flow rate based on the process's maximum,minimum,and normal flow rates.Insufficient flow fails to meet production needs;excessive flow causes the pump to operate long-term outside its high-efficiency zone,increasing energy consumption,temperature rise,and wear risk.Allow reasonable margin for system fluctuations.

2.Head(H)-Energy Metric for Overcoming System Resistance

The energy increment per unit weight of liquid gained after passing through the pump,equivalent to the liquid column height corresponding to the pressure difference between pump outlet and inlet.Unit:m.

Selection Key:Precisely calculate the total system resistance(including frictional losses,local losses,static pressure difference,elevation difference)at the target flow rate.The selected pump's rated head should be slightly higher than the system required head.Note that flow rate and head exhibit an inverse correlation on the pump characteristic curve.

3.Rotational Speed(n)-Lever for Performance and Reliability

Rotations per unit time of the pump shaft.Unit:r/min.

Selection Key:Rotational speed directly impacts output capability and operating state:

Flow Rate∝Rotational Speed

Head∝Rotational Speed²

Shaft Power∝Rotational Speed³

High speed increases flow and head but intensifies wear,noise,heat generation,and cavitation risk;low speed has the opposite effect.Selection requires optimizing speed to balance efficiency,lifespan,and drive configuration while meeting process requirements.

4.Power and Efficiency(P,η)-Core Indicators for Economical Operation

Shaft Power(P):Mechanical power input to the pump shaft.Unit:kW.

Efficiency(η):Ratio of effective power(Pe=ρgQH/3600)to shaft power,expressed asη=Pe/P×100%,characterizing the effectiveness of energy conversion.

Selection Key:Efficiency is critical for evaluating pump energy consumption.High-efficiency pumps indicate reduced mechanical friction,volumetric leakage,and hydraulic losses.Prioritize models with high efficiency at the common operating point.Match drive equipment based on shaft power(including a safety factor).

5.Net Positive Suction Head Required(NPSHr)-Threshold for Stable Operation

The minimum inlet pressure margin(above the liquid's vaporization pressure)required by the pump itself to prevent cavitation.Unit:m.This is an inherent characteristic of the pump.

Selection Key:Critical.The system's Net Positive Suction Head Available(NPSHa)must satisfy:NPSHa>NPSHr+Safety Margin.This condition directly determines the pump's maximum allowable installation height(suction lift).Neglecting NPSHr readily induces cavitation,causing noise,vibration,performance degradation,and severe erosion damage to wetted parts(e.g.,rotors,casing).

Conclusion:

Precise rotor pump selection is essentially the synergistic optimization process of five key parameters:Flow Rate(Q),Head(H),Rotational Speed(n),Efficiency(η),and Net Positive Suction Head Required(NPSHr).Only through a deep understanding of their definitions,interrelationships,and impact on system operation,combined with rigorous calculation and matching for specific working conditions,can a pump be selected that offers matched performance,efficient operation,reliable stability,and optimal economy,thereby providing a solid foundation for smooth and efficient process flows.

Bonve remains committed to the philosophy of"Dedicating Ourselves to Perfecting Rotor Pumps,"striving to provide customized conveying and mixing solutions for global clients.Should you have any technical inquiries,selection needs,case study requests,or other collaboration intentions regarding Bonve rotor pumps in the future,please feel free to contact us anytime.

Service Hotline:0574-87588986 13586591794

Official Website:www.bvpumps.com

Business Email:market@bonvepumps.com

We look forward to partnering with you,driving efficiency and innovation in industrial fluid transfer through precision technology.