Background and Compliance Basis of the Plan The main gearbox of wind turbines is a transmission component that directly affects the operational stability, power generation efficiency, and service life of the wind turbine. The gearbox lubricating oil is exposed to harsh working conditions characterized by high speed, heavy load, and temperature fluctuations over an extended period. This exposure makes the oil susceptible to contamination from mechanical impurities and moisture ingress. Simultaneously, continuous oxidation reactions occur, generating harmful substances such as oil sludge and varnish films. These substances can lead to gear wear, bearing pitting, excessive acid value of the oil, and blockages in the oil circuit, thereby increasing the maintenance costs and downtime losses of the wind turbine.
To standardize the filtration, purification, and operation and maintenance standards for lubricants in wind turbine gearboxes, and to enhance the reliability of the unit’s lubrication system, the country has issued a new version of the national standard: Reference Standard: GB/T 47642-2026 “Guidelines for Lubricant Handling and Replacement of Wind Turbine Generators” (issued on 2026-07-02 and officially implemented on 2026-11-01, currently a national standard to be implemented soon). Standard 4.1.1.1 stipulates that the gear oil in the main gearbox of wind turbines should be filtered online using an online filter with a filter element precision of no more than 10 μm, a filtration ratio β10 of no less than 200, and a particle contamination level during operation of no higher than level −/19/16. This clause clarifies the compliance requirements for the filtration precision, purification efficiency, and cleanliness of the oil in the main gearbox of wind turbines, and serves as an implementation guideline for equipment operation and maintenance, as well as oil product control in wind farms.
In response to national standard requirements and on-site operation and maintenance, Haina has launched a dual-system collaborative purification solution consisting of a bypass purification device and a high-precision online purification filter. This solution takes into account both the compliance filtration of the main system and the deep purification of the bypass, addressing issues such as gear oil impurities, moisture, and oxidative pollution. It aims to achieve the goals of extending oil product lifespan, maintaining equipment, and reducing costs while increasing efficiency.
Haina S Series – Oil Tank Bypass Purification Device The Haina S Series oil tank bypass purification device is an auxiliary deep purification equipment for gearboxes, designed for parallel independent operation. It requires no modification to the main lubrication pipeline of the unit and is compatible with various mainstream wind turbine gearbox models. It is easy to install, simple to operate and maintain, and can operate continuously online for a long time.
- Independent parallel architecture ensures safe and undisturbed operation: The equipment operates independently in parallel with the main lubrication system of the unit, without interfering with the main oil circuit circulation or altering the operating parameters such as pressure, flow, and temperature of the main system. The entire process of equipment startup and shutdown, routine maintenance, and filter replacement does not require the unit to be shut down, does not affect the normal power generation operation of the unit, and avoids the loss due to operation and maintenance downtime.
•Ambient temperature purification technology, safeguarding oil quality: Abandoning the traditional heating and dehydration mode, purification is completed under ambient temperature conditions, avoiding high-temperature environments that accelerate the oxidation, aging, and deterioration of lubricating oil, reducing the rate of oil degradation, and preserving the basic performance of lubricating oil and the activity of additives. - Simultaneous purification of multiple pollutants: It can simultaneously purify solid mechanical impurities, free water, and emulsified water in gear oil, continuously optimizing the cleanliness and water content of the oil. It addresses issues such as water pollution and impurity accumulation caused by large temperature differences between day and night in wind power generation and aging of box seals, compensating for the shortcomings of main-line online filters that can only filter solid particles and cannot remove water.
HNE Wind Turbine Gearbox Online Purification Filter Cartridge (Main System Component) The HNE wind turbine gearbox online purification large filter cartridge serves as a filtration accessory for the main lubrication system of the gearbox. With dimensions of 152 mm × 854 mm, it is compatible with the main online filtration system of the unit and outperforms the GB/T 47642-2026 national standard limits in terms of performance. It is a supporting component that meets the compliance requirements of the new standard and enhances the filtration accuracy of the main system.
Performance parameters
- Filtration performance: The filtration ratio β10 for 10 μm particles is ≥ 2000, corresponding to a filtration efficiency of 99.95%. It can intercept key abrasive particles in the oil, ensuring that the particle pollution level during unit operation remains stable within the −/19/16 range.
- Pollution holding capacity: With a pollution holding capacity of >800 g and a terminal pressure drop of 400 kPa, it exhibits improved pollution holding capacity compared to conventional filter cartridges. This extends the service life of the filter cartridge, reduces the frequency of filter cartridge replacement, and lowers operation and maintenance consumables and labor costs.
- Dehydration capacity: Utilizing composite adsorption and filtration materials, a single filter cartridge can absorb up to 3.2 kg of water, specifically adsorbing trace amounts of moisture in oil products and improving oil emulsification issues.
Purification function
- Water purification: It can purify three types of water forms in gear oil: free water, emulsified water, and dissolved water. Water is the cause of oil emulsification, additive failure, metal component corrosion, and lubrication performance degradation. Dehydration can improve the hidden fault risk of water ingress in gearboxes.
- Solid impurity removal: Relying on high filtration accuracy, it intercepts micron-sized wear particles, dust, metal debris, and other impurities, continuously optimizes the cleanliness of the oil product, stably meets the national standard operating cleanliness requirements, and reduces equipment damage caused by hard particles such as gear mesh wear, bearing scratches, and oil passage wear.
- Inhibiting oil oxidation and aging: Capturing oil oxidation products, suspended oil sludge, and varnish precursors, blocking the chain reaction of oil oxidation, inhibiting the rapid increase of oil acid value, delaying the aging and deterioration of lubricating oil, and extending the oil change interval.
The overall application value of the solution: This dual-system purification solution is highly compatible with the new version of the national standard GB/T 47642-2026. Through the coordinated purification of the main and auxiliary systems, it achieves the control of “impurity removal, dehydration, anti-aging, and acid value suppression” of wind turbine gearbox oil. On the one hand, it ensures the compliant operation of the unit equipment and avoids compliance risks after the implementation of the new standard; on the other hand, it reduces the occurrence rate of gearbox failures, decreases the frequency of filter replacement, extends the service life of lubricating oil, and reduces the annual operation and maintenance costs and downtime power generation losses of wind farms, steadily improving the operational stability and economic benefits of wind turbine generators.
