In the field of industrial coating, Coating Equipment Gear Metering Pumps have become the preferred choice for numerous high-demand applications due to their precise metering capability and stable fluid transfer performance. However, selecting the most suitable pump type is crucial when faced with varying operating conditions and media. Currently, the common gear metering pumps on the market are mainly categorized into involute gear pumps, helical gear pumps, and herringbone gear pumps. While these three pump types share similar basic principles, they each have distinct performance focuses. This article provides a detailed comparative analysis of them.
I. Involute Gear Pump: An Economical and Practical Basic Option
The involute gear pump is the most common and widely used type, characterized by gears with a standard involute tooth profile.
l Performance CharacteristicsAdvantages: Mature manufacturing technology, relatively low cost, compact structure, and high self-priming capacity. It delivers reliable transfer performance under rated operating conditions.
¡ Disadvantages: Its primary drawback is the noticeable pulsation in output flow. This is caused by the uneven volume change rate of the enclosed cavity resulting from the shifting meshing points during gear engagement. Additionally, it generates relatively high noise and vibration during operation.
l Applicable Scenarios: Ideal for general coating applications where cost sensitivity is high and extreme flow uniformity is not required. Examples include primer spraying with high tolerance for orange peel effect on coating surfaces, primary anti-corrosion coating, or transfer of medium-viscosity single-component coatings. For users with limited budgets and non-stringent operating conditions, it remains an economical and practical choice.
II. Helical Gear Pump: An Advanced Option with Balanced Performance
The helical gear pump can be regarded as an upgraded version of the involute gear pump, featuring gear teeth arranged at a helix angle rather than parallel to the shaft axis.
l Performance CharacteristicsAdvantages: The most significant improvement is the substantial reduction in flow pulsation and operational noise. Helical gear meshing occurs in a gradual, continuous process, with more teeth engaging simultaneously, resulting in smoother and more consistent flow output. This stability also minimizes vibration, which helps extend the service life of bearings and seals.
¡ Disadvantages: The manufacturing process is more complex than that of involute gears, leading to higher costs. Furthermore, helical gears generate an axial thrust during operation, necessitating thrust bearings capable of withstanding axial loads, which adds slight complexity to the structure.
l Applicable Scenarios: Suitable for applications requiring high-quality coating surfaces. Examples include automotive topcoat spraying, high-end electronic product casing coating, and home appliance exterior part coating. These applications demand minimal pulsation to prevent flow marks or orange peel defects. Helical gear pumps strike an excellent balance between precision, stability, and cost, making them the preferred choice for many mid-to-high-end coating lines.
III. Herringbone Gear Pump: A Professional Option for Ultimate Stability
The herringbone gear pump boasts a more advanced design, with gears shaped like a “herringbone” and composed of two symmetrical rows of helical teeth on either side of the central axis.
l Performance CharacteristicsAdvantages: It perfectly combines the dual benefits of high stability and zero axial thrust. The symmetrical helical tooth structure cancels out axial forces internally, eliminating the need for complex thrust bearings. Meanwhile, it inherits the advantages of helical gear pumps, including ultra-low flow pulsation and quiet, stable operation, and often surpasses them in terms of smoothness.
¡ Disadvantages: The manufacturing process is the most complex, with extremely high machining precision requirements, making it the most costly among the three types. Gear machining and assembly also present greater challenges.
l Applicable Scenarios: Designed exclusively for the most demanding industrial applications. It is particularly suitable for transferring ultra-high viscosity media (such as paste sealants and high-solid-content coatings), precision coating processes requiring absolutely no pulsation (such as optical film and lithium battery electrode coating), and clean room environments with strict noise restrictions. When process requirements are extremely stringent and budget permits, the herringbone gear pump is undoubtedly the performance leader.
Characteristics | Involute Gear Pump | Helical Gear Pump | Herringbone Gear Pump |
Flow Stability | Poor, obvious pulsation | Good, minimal pulsation | Excellent, ultra-low pulsation |
Operational Noise | High | Low | Very low |
Axial Thrust | None | Exists, requires thrust bearings | None, internally offset |
Manufacturing Complexity & Cost | Low | Medium | High |
Core Application Fields | General, cost-effective applications | Mid-to-high-end, high surface quality requirements | Ultra-high precision, high viscosity, harsh environments |
Comprehensive Comparison and Selection Recommendations
In summary, there is no absolute “best” option when selecting a Coating Equipment Gear Metering Pump — only the “most suitable” one. Users need to make a comprehensive trade-off based on their process requirements (such as coating surface quality standards), the characteristics of the transferred medium (especially viscosity), project budget, and expectations for long-term equipment operational stability. Understanding the performance differences between these three common pump types is a key step toward making the right selection, optimizing production efficiency, and ensuring the quality of final products.
Your email address cannot be published. Required fields are marked*
No comments