High Cost of Core Components
As the core component, the rotor pump features a complex structure (such as dual-rotor meshing design) and requires high machining precision (to ensure minimal clearance between the rotor and pump body to avoid leakage). It is typically manufactured from stainless steel or wear-resistant alloy materials, resulting in a high cost for the pump body itself.
Cost of Automation System Integration
The equipment requires supporting intelligent components such as a high-precision PLC control system, weighing sensors, and a touchscreen human-machine interface. Additionally, dual-head filling necessitates synchronous control of two sets of filling pipelines and valves, further increasing hardware costs.
High Initial Investment Threshold
Compared with traditional single-head filling machines or centrifugal pump filling machines, the procurement cost of a full-automatic dual-head rotor pump filling machine may be 30%–50% higher, posing significant pressure on small and medium-sized enterprises (SMEs) during initial adoption.
Rotor Wear Risks
When filling high-viscosity paints (such as thick paste coatings or putties), the frictional resistance between the rotor and pump body increases significantly. Long-term operation may cause wear on the rotor edges or the inner wall of the pump body, affecting metering accuracy (errors may expand from ±0.1% to over ±0.5%) and even causing equipment jams.
Increased Energy Consumption
To push high-viscosity materials, the motor needs to output greater torque, leading to a 20%–40% increase in energy consumption compared to filling low-viscosity paints, which raises production costs over time.
Higher Cleaning Difficulty
High-viscosity paints easily adhere to the gaps between rotors and the inner walls of pipelines. Cleaning requires specialized solvents (such as xylene) or high-temperature flushing, which takes longer (single cleaning time may extend from 30 minutes for low-viscosity paints to over 1 hour) and increases solvent consumption, raising environmental treatment costs.
High Requirements for Precision Component Maintenance
Sealing components of the rotor pump (such as mechanical seals and O-rings) are prone to aging under frequent start-stop operations or high-pressure environments and need to be replaced every 3–6 months (frequency depends on usage intensity). Otherwise, paint leakage or air infiltration may occur, affecting filling accuracy.
Dependence on Professional Technology
Calibration of the equipment (such as weighing sensor calibration and rotor clearance adjustment) must be operated by trained technicians and is difficult for non-professionals to complete independently. If an enterprise lacks maintenance capabilities, it must rely on suppliers for on-site services, potentially causing additional downtime losses.
High Cost of Spare Parts Replacement
Core spare parts such as rotors and seals are typically custom-designed, with long procurement cycles (may take 1–2 weeks) and high costs (a single rotor assembly can cost thousands of yuan). Sudden failures may lead to production line downtime.
Large Footprint
Dual-head filling requires two sets of independent rotor pumps, pipelines, and filling heads. The overall dimensions (length × width × height) of the equipment are usually over 50% larger than single-head models (e.g., a single-head model is approximately 2×1×2 meters, while a dual-head model may reach 3×1.5×2.5 meters), placing higher demands on factory space and layout.
Complex Installation and Debugging
Ensuring synchronization of the two filling systems (such as consistent flow rates and weighing feedback) requires precise calibration of mechanical positions and control system parameters during installation. The debugging cycle is long (may take 3–5 days), increasing preparation time for new production line launches.
Backflow Risks
For extremely low-viscosity paints (such as water-diluted coatings), backflow may occur due to material self-weight when the rotor pump stops, leading to insufficient filling or dripping (even with anti-drip valves, complete sealing may fail due to excessively low viscosity).
Suboptimal Efficiency
Low-viscosity paints are more suitable for rapid transportation by centrifugal pumps or gear pumps. The volumetric efficiency of rotor pumps in low-viscosity scenarios may be lower than that of centrifugal pumps (e.g., a difference of 10%–15%), resulting in underutilized production capacity.
High Noise Levels
Mechanical noise (approximately 70–85 decibels) may be generated during rotor meshing, requiring soundproof enclosures or installation in independent workshops, which adds extra costs.
Sensitivity to Paint Particles
If paints contain large solid particles (such as sand or pigment agglomerates), they may clog the rotor gaps (typically only 0.1–0.3 mm), causing equipment failures and requiring additional precision filtration devices.
The main drawbacks of this equipment focus on cost, maintenance complexity, and viscosity adaptability. It is more suitable for large-scale, high-precision filling of medium-to-high-viscosity paints (such as industrial anti-corrosion coatings and automotive paints). If enterprises need to handle low-viscosity paints or have limited budgets, consider the following solutions:
Combine with auxiliary equipment: Equip wear-resistant coated rotors for high-viscosity scenarios and add anti-backflow valves for low-viscosity scenarios.
Phased investment: Adopt a single-head rotor pump filling machine first, then upgrade to a dual-head model as production capacity expands.
Choose customized services: Collaborate with suppliers to optimize sealing designs or pipeline layouts to reduce maintenance frequency.
When selecting equipment, comprehensively evaluate paint characteristics, production capacity requirements, and budgets to balance equipment performance and costs.
