Handheld probing solution keeps wind turbines turning

Goldwind - China


Globally, wind power generation increased more than fivefold since the year 2000. With the global trend toward limiting CO2 emissions and numerous governmental programs subsidizing or financing wind power generation, its share of global power generation is set to experience substantial growth in the foreseeable future.

China is rich in wind energy, with about 1,000 gigawatts of potentially exploitable wind energy. This energy potential is distributed across the southeast coastal areas, adjacent islands, Inner Mongolia, Xinjiang, the Gansu Hexi Corridor, Huabei and the QinghaiTibetan Plateau. In order to encourage technical innovation, market expansion and commercialization, development targets have been established, concession projects offered, and policies introduced to encourage domestic production.

Three-dimensional measurement and analysis of rotor blade hubs and their production facility are highly complex and demanding measuring tasks. Such measurements can be successfully dealt with only by using modern measuring systems and a well-prepared measurement strategy.

Increasing rotor blade sizes Transferring the rotors energy efficiently to the main bearing and withstanding the enormous windload constantly, brings another critical part into focus, the main hub. The hub connects the three blades to form the rotor and is holding, depending on the model of wind power generator, the motorized pitch mechanism for each blade. The rotor itself is joint to the slowly rotating shaft or main bearing with another flange, thus forming a rigid horizontal rotation-axis into the nacelles gear box.

Diameter, flatness and orientation of each flange of the hub are subject to precise quality inspections. Leica T-Probe, the walkaround-CMM, perfectly matches to the need of accuracy and ease of use. Connected to a state of the art metrology software Metrolog XG for Leica this one-man operated probing device enables Goldwind Science and Technology to quickly inspect and document the machined part as-build directly on the shop floor. Due to the wireless Leica T-Probe’s capability of measuring hidden points without direct line of sight to the lasertracker more than one interface of the hub can be verified without changing the set-up. Combined with the large volume this advantage can be extended to the inspection of multiple hubs from one and the same set-up of the instrument. When Goldwind compared several measurent solutions, there was no other highly exact CMM on the market that offered so much freedom to move.

All CMM advantages without transporting parts to a measurement lab:

The Leica T-Probe gives Goldwind all the advantages of a fixed CMM, but without the need for a measurement lab and a time consuming logistic process to move heavy parts to the CMM table. Previously, all those inspections were carried out using dial gauges, micrometers and calipers. Mastered by experienced users these instruments were very accurate and gave enough two dimensional information. But due to the increased size and numbers of parts to be inspected, it became more and more a bottleneck in throughput and maintaining accuracy. Furthermore computer aided design and modern quality management in the highly competitive business of wind power energy sets a new level of expectation to a 3D metrology device. After some training days, all future users of the laser tracker-based system knew how to operate hard- and software. Replacing some tenth of mechanical measurement tools by a modern CMM means a major investment that clearly has to be justified. First results and feedbacks show perfectly the benefit of this investment. The acceptance of the system from the workers is great and the potential to expand the measurement task to different applications will return the investment within shortest time.

Anticipating customers’ needs:

Leica Geosystems has been a reliable partner for the wind energy industry from the beginning. In this very dynamic business, the Swiss high-tech company developed numerous specific measurement solutions and gained a lot of experience. Many marketleading wind energy companies trust in Leica Geosystems’ know-how. Wind power parts grow continuously as wind power plants become larger and larger. The Leica Absolute Tracker enormous measurement range shows how Leica Geosystems anticipates customer needs.