Inside service

HMF, in Denmark, has modified one of its loader cranes to fit into 2 to 3 MW wind turbines. It is used to carry out maintenance and lift material from the ground, using a chain hoist.

The loader is a modified standard hydraulically operated 2.6 tonne capacity HMF 260T, renamed HMF 265T.

It is placed on one side of the engine room on a solid base. From here it is able to reach components for service, repair or renewal.

"In service loads can be up to maximum crane capacity, but normally less then half of the crane capacity is used," explains René Dahlkilde, product manager.

To customise the crane, HMF is provided with a complete map of the engine room, showing all parts to be serviced.

"We modify the loader controls and the reach if necessary. It has to be safe and easy to operate. The lifting reach and capacity are tested and approved on the ground before the loader is fitted. Requirements for oil cleanliness, power supply and speed, etc, according to manufacturer specifications, are adopted into the loader specifications."

The HMF 265T has a maximum reach of 3.5 m and lifting capacity is 1.8 tonnes at 1.5 m.

"The combination of hydraulic manoeuvrability up and down, combined with hydraulic extensions and hydraulic slewing mechanism, makes it easy to place the hook exactly where it is needed and service the different components at their exact position. If components cannot be reached by the hydraulic reach, it is possible to fit manual extensions at the end of the arm system," adds Dahlkilde.

He comments that demand for larger loader cranes in turbines will increase along with their MW outputs. "Capacity and reach will continue to grow, and I am sure that features such as radio controls will be of great interest for more flexibility and safe work practices. Specific demands on speed and additional safety features will follow."

HMF mounts its truck loader safety system RCL 5300 on all cranes designed for wind turbines. The RCL 5300 has a range of analogue and digital in- and outlets and uses CAN-bus, which makes it easy to incorporate additional safety features, says the company.