Gear Pump Selection for Diesel Fuel

Based on the customer's requirements for selecting a gear pump for diesel transportation, and considering the medium, viscosity, temperature, flow rate, pressure, and motor
parameters provided, the KCB series gear pump is recommended as a reasonable and technically suitable choice. The following is a detailed analysis:

 

I. Selection Reasonability Analysis

Media Compatibility

The KCB series gear pump is suitable for transporting liquids such as diesel and lubricating oil. The customer's media are vacuum crude oil and diesel, which fit within the pump's applicable range.

Viscosity and Temperature Compatibility

The customer's diesel viscosity is 12-20 cSt. The KCB series can handle viscosities ranging from 5 × 10⁻⁶ to 1.5 × 10⁻³ m²/s (approximately 5-1500 cSt), fully meeting the requirements.

Operating Temperature 150°C: The KCB series pump body is made of cast iron, which generally has a temperature resistance of over 200°C, making it suitable for high-temperature operating conditions.

 

Flow and Pressure Matching

The customer required a flow rate of 36 L/min, and the recommended KCB83.3 had a rated flow rate of 83.3 L/min. Although this exceeded the required flow rate, it could be precisely controlled
by adjusting the motor speed or valve opening, leaving some performance margin.

The customer's pressure requirement was 4 bar (0.4 MPa), which exactly matched the KCB83.3's discharge pressure (0.4 MPa).

 

Motor Parameter Matching

Customer motor parameters: 440V, 60Hz, 1030 rpm, 1 kW.

Recommended pump parameters: 440V, 60Hz, 1450 rpm, 2.2 kW.

Speed Discrepancy: The customer's motor speed (1030 rpm) is lower than the pump's rated speed (1450 rpm). Adjust the pump speed to a matching value using a pulley or inverter,
or confirm whether the motor can increase to 1450 rpm.

Power Discrepancy: The pump's rated power (2.2 kW) is higher than the customer's motor power (1 kW). A 2.2 kW motor was required to ensure drive capacity and avoid overload.

 

II. Core Advantages of the KCB Series Gear Pumps

Structure and Performance

The external gear pump design offers a compact structure, high speed, and large displacement, making it suitable for high-pressure and high-flow applications.

The heat-treated gears provide high hardness, strong wear resistance, and long life.

A built-in safety valve prevents overpressure and protects the system.

 

Sealing and Explosion-Proofing

The shaft end seal utilizes a mechanical seal, suitable for low-viscosity media such as diesel, to prevent leakage.

The gears are available in tin bronze, meeting explosion-proof requirements and preventing sparks for safety.

 

Maintenance and Cost

The simple structure allows for easy maintenance and low cost.

The strong self-priming capability eliminates the need for additional priming and is easy to operate.

 

III. Optimization Recommendations

Motor Matching

If the customer's motor cannot reach 1450 rpm, consider:

Replacing with a 2.2 kW 1450 rpm motor.

Selecting a KCB series model with a flow rate closer to the required flow rate (e.g., KCB33.3, flow rate 33.3 L/min, pressure 0.33 MPa), but confirm that the required pressure is met.
Material Upgrade

If the media contains corrosive components, the pump head material can be upgraded to stainless steel (such as 304/316) to extend service life.

Drive Type

Magnetic coupling drive is recommended to prevent leakage and is suitable for applications with strict sealing requirements.

 

IV. Conclusion

The KCB83.3 gear pump is a reasonable recommendation, but the following considerations apply:

 

The motor power needs to be upgraded to 2.2kW, or the pump speed needs to be adjusted to match the existing motor.

 

Confirm the compatibility of the pump and motor speeds and adjust them using a transmission device if necessary.

If the customer requires high flow accuracy, a frequency converter can be added for precise control.

This solution offers excellent media compatibility, temperature and pressure compatibility, structural reliability, and cost-effectiveness, meeting the customer's needs for
long-term stable operation.