Working with wind

With wind energy moving in to the mainstream, turbine manufacturers are striving to increase productivity and quality while driving down costs. E&T visited several Vestas facilities in Scandinavia to assess their improvement efforts.

The market for wind energy is booming, but while that increased production may seem a boon for wind turbine manufacturers, it comes at a cost. With competition mounting, the costs of turbines are coming down, and that is putting greater and greater pressure on manufacturers to become lean and flexible.

These two words are nothing new in the sphere of manufacturing but for Vestas, market leader in wind turbines, they are a new challenge. Visiting Vestas factories in Denmark and Norway, one cannot help but be impressed as they strive to match the productivity and flexibility that is common place among automotive manufacturers, but with products that would dwarf your average car.

As part of a revamp of its manufacturing facilities to meet the coming challenges - which unfortunately also saw the closure of its Isle of Wight blade factory - the company has started a '12 must-win battles' campaign. Started last year, this is already showing significant gains across the company, including its blades, nacelles, control systems and casting divisions.

Improved production, enhanced product flow, better safety and continuous improvement are just some of the benefits that Vestas is claiming. At the Nakskov blade manufacturing facility in Denmark, it has achieved an impressive 45 per cent year on year improvement in the number of blade shells manufactured per week, for example.

As a change, agent professional Sanne Nørgaard has been closely involved in putting the new work principles into practice at the shell department, working closely with the Quality and Production Engineering support departments. "There was a bottleneck here at the shell department, and this is also where the most expensive equipment is located," Nørgaard explains. "That made it a natural place to start, because there were major benefits to be gained here by making better use of the existing equipment."

The process began in early 2008 after a visit to a Vestas sister facility in Lauchhammer, Germany. The ideas were subsequently refined by managers, support departments and a number of employees at a workshop before the principles were applied in practice at the factory.

"Of course, not everyone is equally happy to have to change the way they work, and some people are still not convinced," says Torben Holm Jensen, who works in the shell department himself. "But I can clearly sense the enthusiasm in many of my colleagues. This is underlined by the fact that many more suggestions for improvements are now coming from the individual teams," he adds.

"People are proud that our production is now higher than it was before, and that, at the same time, the quality of the blades has improved. For example, there is no longer as great a need to add extra adhesive to the blades because we have streamlined the way we apply it."

The ongoing improvements are included on the agendas at the notice-board meetings each team holds daily. "Openness is crucial to ensuring that everyone is fully familiar with the decisions and can see which way we are heading. This is something we have learned during the process. We were not good enough at involving everyone at the start, and that caused frustration among some of the employees," says Nørgaard, who believes that the policy of making managers more visible has played a key role in the success.

Not all employees were immediately appreciative of the production improvements, and they were met by some of the early cynicism that is common to most improvement programmes. "I originally suspected that this initiative was designed to make us work harder and faster at the factory," Brian Sølberg, employee representative at the factory says. "But I now know that this is not what it is all about.

"In fact, the new system is designed to help us make the work easier for ourselves and to eliminate the waste that clutters up the processes today."

Building on experience

Production excellence is built on the experience already gained at Vestas from systems such as Lean and TPM. "A lot of people think that they will be pressured into working faster every day to increase production figures. However, it is more a matter of working smarter, not harder," explains Jan Nielsen, lean manager, continuous improvement, who emphasises how important it is that the proposals for improvements come from employees - because they have hands-on experience of the work processes.

"We need greater standard-isation of the way we manufacture at Vestas so we can really start to exploit the fact that we have a giant organisation and can share best practice between our factories," Nielsen adds.

It is not only improved production that is a target of the campaign, but better safety and quality. Last year Vestas Nacelles plants registered an incidence of industrial injuries of 13.9 per million working hours, compared to 23.5 the year before. The achievement came on the heels of a 30 per cent reduction in incidence of industrial injuries from 2006 to 2007 - an injury defined as a lost-time injury requiring at least one day's absence from work.

Bo Kokholm Pedersen, director of environment and safety in Vestas Nacelles, puts the improvement down to the unwavering commitment of both management and shop-floor employees. "We will not accept that anyone works unsafely," he says. "This year we have had around 195 managers and safety representatives on a three-day safety course. Knowledge sharing between factories is also taking off to develop minimum safety standards, and an idea catalogue of factory initiatives is available online."

He expects a new approach to risk assessments, introduced last year, to bring further long-term safety improvements. Trained safety personnel - risk guards - carry out the assessments, when they observe production processes and evaluate the associated risks, based on the likelihood and potential severity of an industrial injury.

During the year, special focus was placed on the five Vestas Nacelles factories that had experienced most industrial injuries. One of them was the casting plant in Kristiansand, Norway, where risk guards are now in place in all six of the plant's departments. Their systematic inspections have highlighted a series of minor and major issues which are now being addressed, says project leader Hilmar Marøy.

"Our safety record was not good, with too many small industrial injuries such as people getting their hands pinched. One of the things the risk guards noted was that some equipment that was bolted to the floor had been removed but the bolts were still there to trip over. We also lacked good solutions for working at heights."

Foundry workers at Vestas Castings in Magdeburg are hard pushed to remember a time when continuous quality improvements were not part of their everyday work. But with the introduction of 130 process CTQs - critical to quality parameters - foundry standards have moved to a new level. Four Sigma, to be precise.

By fine-tuning specifications for incoming raw materials and stepping up the evaluation of casting processes, Magdeburg staff have upped the quality of key components such as rotor hubs, and cut waste to just 1.7 per cent. Not bad when you consider the challenges involved in controlling the quality of cast iron components that weigh somewhere between 100kg and 11t, and are produced from 17,000t of raw materials a year.

"Factory staff are closely involved in defining the CTQs, and they are also responsible for informing the foreman if there is a deviation," says quality manager Steffen Hupfeld. "In the case of difficult CTQ questions, we have a lot of support possibilities, for example the raw material suppliers and special test laboratories. Production is a living system, and we have to improve all the time."

A large number of CTQs relate to the raw materials. One in particular concerns the presence of a specific trace element in the iron, which has been found to have a negative impact on the structure of thick-wall castings. Now they keep this in check through chemical analyses, and this has stabilised quality markedly.

In the shop floor discussions about scrap reduction, persistence has proven a real virtue, says Hupfeld. The dialogue and investigations have simply continued until goals are achieved. For example, shrinkage, caused by errors in the casting volume, was a major contributor to foundry scrap levels - but no longer, following implementation of the appropriate CTQs. "This defect, detected by ultrasonics, has almost disappeared over the past year," Hupfeld continues.

One thing that is apparent from anyone who has been involved in any improvement programme, whether it be under the lean banner, Six Sigma or any other quality programme, is that management buy-in is essential. Many a well constructed strategy has floundered because middle and senior managers pay little more than lip service to the process, and that is something that Vestas was desperate to avoid.

"Being a manager is hard work if we are to achieve results," says Jan Neilsen. "We can see that when managers take the lead, results are being achieved. It has to do with the very reason for existence of individual factories - and of Vestas itself. Quite simply, we have to take things to a whole new level in the future if we are to remain competitive and fully meet customers' requirements."

Redefining management

For the mission to succeed, managers at all levels need to realign their positions, as Per Thiesen, Vestas' battle manager, explains: "Continuous improvement is the order of the day, and the factories that do best in the future will be the ones where the managers take the lead.

"At the same time, redefining the management role is the greatest challenge in the project - the managers are finding it most difficult to change."

One of the biggest challenges involves training managers and middle managers to organise their time differently - away from the desk and out onto the shop floor. The ultimate aim is for the senior managers at the factory to spend half their time on the shop floor, while middle managers and team leaders are there 80 per cent of the time.

"When managers are present in the production areas, this naturally results in them taking action and making decisions if anything needs to be changed," says Nielsen. "This is where problems have to be solved from day to day. If employees encounter a problem, the managers must be on hand to do something about it."

There may yet be more work to do for Vestas as it attempts to ramp up production to meet the expected growth in demand, but the foundations of the past 18 months will set it well on the road.

Recent articles

Info Message

Our sites use cookies to support some functionality, and to collect anonymous user data.

Learn more about IET cookies and how to control them