As wind turbines grow in height and capacity, maintenance is becoming more demanding. Taller towers mean longer lifting distances for tools, spare parts and other equipment, increasing the pressure on operators to minimise servicing time without compromising safety.
Lifting equipment is therefore receiving greater attention. RUD’s neXera electric hoist has been developed for wind turbine maintenance, with a focus on reducing lifting times while addressing safety, reliability and serviceability.
Reducing the journey to the nacelle
Designed for loads of up to 800 kg, the hoist operates at variable lifting speeds from 24 m/min at full load to 80 m/min with no load. The control system automatically adjusts speed according to the measured hook load.
RUD says the system can complete lifting and lowering operations in approximately one quarter of the time required during a typical service cycle using conventional equipment.
The main specifications include:
At the centre of the system is RUD’s patented X-Drive chain technology, designed to permit higher chain speeds while limiting wear.
Adapting to taller turbines
Increasing hub heights are changing maintenance requirements. Onshore developers are reaching higher altitudes to access stronger and more consistent wind resources, while offshore turbines continue to increase in size.
Traditional hoists designed for earlier turbine generations can mean longer waiting times for technicians, particularly when multiple lifts are required during a service visit.
RUD says an 800 kg payload can be transported to a height of 200 m in approximately eight minutes. The time difference can become particularly significant when empty lifts are included, as these can operate at up to 80 m/min.
According to Matthias Müller, Technical Manager in Drive Development at RUD Drives, transporting the tools and auxiliary materials required for maintenance can take around two hours with conventional hoists. RUD claims neXera can reduce this to approximately half an hour.
Actual savings will depend on the turbine, site and maintenance programme, but reducing non-productive lifting time could help shorten turbine shutdowns and make better use of restricted offshore weather windows.
Safety alongside speed
Higher lifting speeds also require careful attention to operational safety.
The hoist incorporates an incremental encoder that allows precise upper and lower hook positions to be defined. By monitoring drive-shaft rotation, the system is designed to provide repeatable positioning and reduce the risk of incorrect hook placement.
Other safety and operational features include:
These measures are intended to reduce risks when handling equipment in the confined and vertically challenging environment of a wind turbine.
Making maintenance easier
Serviceability is another consideration. Faster lifting provides little benefit if the hoist itself causes additional downtime.
RUD has therefore used a modular design that allows individual components to be accessed and replaced without extensive disassembly. Electrical components and the control system can also be housed separately from the main hoist, improving access while protecting sensitive equipment from vibration.
Digital recording captures information such as load cycles and usage patterns within the frequency converter. According to RUD, these records cannot be altered and can support inspection and servicing requirements under DIN EN 14492-2.
As wind fleets grow and existing turbines age, maintenance workloads will increase. Faster hoisting alone will not transform turbine servicing, but reducing waiting time, improving equipment access and maintaining reliable operating records can contribute to more efficient maintenance.
As turbines continue to become taller and more demanding to service, the equipment used to maintain them will need to develop alongside them.
Explore the full feature on high-speed hoisting, turbine maintenance, safety and reducing servicing time from RUD in PES Wind: https://pes.eu.com/exclusive-articles/the-race-to-the-nacelle