How should the fan gearbox be purchased?

As we all know, gearboxes are the most important and most expensive components in wind turbines. Therefore, the selection of a reliable, well-functioning gearbox is the key to providing a high quality wind turbine. Ende, as a world-renowned and rigorous wind turbine supplier, has developed a complete and rigorous quality control process for its gearbox suppliers. Ender Group implements uniform process requirements and strictly controls the quality of its components in all its subsidiaries worldwide.

Ender's General Engineering Department in Germany is responsible for the development of all technical specifications for gearboxes, including load specifications. This team is considered to be one of the most rigorous and reliable technical teams in the wind turbine manufacturing industry; as this department is the only department in the world responsible for auditing the qualification of gearbox suppliers, thus ensuring the uniform quality standards of Ende products.

The first step in selecting a supplier is to screen the potential suppliers in the market by the Engineering Department's Collaborative Purchasing Department and Quality Department. Next, the three departments conduct pre-assessment of the primary suppliers to determine the target suppliers. For the identified target suppliers, Ende will evaluate their technical strength, production capacity, management and other technical indicators. Ender will provide suppliers with relevant technical specifications and drawings, and sign a confidentiality agreement with the target supplier. Ende requires suppliers to produce parts in strict accordance with technical specifications, and deviations are accepted only after discussion and confirmation by both parties.

In general, the qualification of a gearbox supplier requires three steps: prototype testing, small batch production, and mass production. Ende will first order two gearboxes as prototypes. At this stage, all technical requirements are discussed and determined. Suppliers are required to provide all necessary documentation and calculations, including quality monitoring reports and finite element calculations. The prototype will then be tested on the prototype according to Ender's test specification, including sound and vibration tests. The prototype was accepted only when the test results met Ender's requirements. In addition, the gearbox must also be GL certified and certified.

After the prototype test is successful and relevant documents are issued, the prototype is allowed to be installed in the wind farm for field testing. Field testing can take at least a year or a corresponding number of hours of operation. During this period, it will be regularly tested, including vibration monitoring, oil sample testing and endoscopy. After at least one year of field testing, the prototype can be removed from the fan and thoroughly inspected in the supplier's factory, including bearing inspection. According to the results of the inspection, Ender will decide whether to proceed to the next step, small batch production. In the pilot production phase, the order quantity is usually in the range of 10-20 units to further confirm the production quality. Ender will strictly monitor the production process at this stage and guide the operation of the site in detail. Mass production can only be carried out when the production quality of the gearbox is stable. Therefore, it takes at least two and a half years from the selection of the gearbox supplier and the quality compliance to be able to mass produce.