Metering Pumps for Oil-Based Pigments and Additive Dispersions

 

For selecting a metering pump for oil-based pigments and additive dispersions, considering viscosity, flow rate, pressure, temperature, and control requirements, a 1.5CC gear metering pump with a servo motor and integrated PLC control system is recommended. The specific analysis is as follows:

 

1. Core Selection Basis

Viscosity Compatibility: Oil-based pigment dispersions have a viscosity of 2000-6000 cp (i.e., 2-6 Pa·s), classifying them as high-viscosity media. Gear metering pumps achieve volumetric delivery through gear meshing, exhibiting strong adaptability to high-viscosity media. This ensures stable and pulsating flow, avoiding flow attenuation or leakage problems caused by excessively high viscosity.

 

Flow Rate and Pressure Matching

 

Flow Rate Range: The required flow rate is 1-9 L/h, and the 1.5CC gear pump's displacement design can cover this range. By adjusting the servo motor speed (e.g., 1-300 rpm), linear flow control can be achieved, meeting the needs of precise adjustment at small flow rates.

 

Pressure Capacity: Under a back pressure of 1-3 bar, the rated pressure of the gear pump is typically higher (e.g., 4-6 bar), easily overcoming pipeline resistance and avoiding cavitation or flow fluctuations.

 

Temperature Compatibility:

 

The fluid temperature is 5-35℃. The gear pump and servo motor can operate stably within this range without special cooling or heating devices.

 

2. Advantages of Servo Motor and PLC Control:

 

Precise Speed ​​Control: The servo motor achieves closed-loop control through encoder feedback, with a speed accuracy of ±0.1 rpm, meeting the requirements for "very low speeds" (e.g., below 1 rpm).

 

Torque output is maintained even at low speeds, preventing gear pump jamming or unstable flow due to excessively low speed.

 

PLC Integration Functions:

 

Real-time Feedback: The PLC can read parameters such as servo motor speed and torque and convert them into flow signals (calculated by displacement × speed), achieving closed-loop flow control.

 

Automatic Adjustment: The PLC can dynamically adjust the speed according to process requirements (e.g., automatically compensating for flow based on changes in pigment concentration), improving system response speed.

 

Fault Diagnosis: Monitors motor current, temperature, and other parameters to provide early warnings of overload or stall risks.

 

Expandability: The PLC system can reserve interfaces for future integration of pressure sensors, flow meters, and other devices to achieve more complex control logic (such as pressure-flow modulation).

 

3. Implementation Recommendations

Pump Body Material Selection: Based on the medium composition, stainless steel (e.g., 316L) or Hastelloy is recommended for the pump head. PEEK or silicon carbide can be selected for flow-through components (gears, bushings) to resist pigment abrasion.

 

Servo Motor Selection: Power: Select based on maximum speed and torque requirements (e.g., a 0.4kW servo motor can meet the requirements of a 1.5CC pump).

 

Encoder Resolution: Prioritize absolute encoders with 20 bits or more to ensure position feedback accuracy at low speeds.

 

PLC Configuration: Input: Receives speed setting signals (4-20mA or Modbus RTU).

 

Output: Controls servo drive start/stop and speed adjustment, and feeds back the actual speed/flow to the host computer.

 

If you have specific questions regarding the selection and pricing of chemical metering pumps and industrial transfer pumps, please feel free to contact Winny at CIXIFM:

Email: sales01@cxflowmeter.com

WhatsApp: 008618049841995