Gearbox Express Makes Waves with Brüel & Kjær

See the full article as published in Brüel & Kjær Waves

Addressing a need that the market is only just learning of, a group of gearbox experts are set to bring a new approach to the industry: an exchange inventory of gearboxes rebuilt to exacting standards – by a company dedicated to just that.

The wind power industry is young but developing, and with that maturation comes the exploitation of market niches by specialists. Gearbox Express is one such company that is set to hit the ground running after making a serious investment in a high-tech approach to gearbox remanufacturing. Scheduled to open their doors in early May, they are ready to bring a new concept to the US wind energy industry: remanufacturing gearboxes with OEM gearing and upgraded bearings and then swapping them wholesale for their worn-out predecessors.

Marketplace opportunities

The wind energy market today includes a segment of companies that repair and overhaul gearboxes, and as more turbines are installed and current installations age, the need for servicing expands. At present, there are about 26 000 megawatt-class turbines installed in the US, and it is a simple fact that their gearboxes will need replacement over the next seven years or so. So it is no overstatement to say that repairing them will potentially be a multi-billion dollar industry.

According to Gearbox Express’s CEO Bruce Neumiller, “There is going to be a rude awakening as to the volume of gearboxes that will fail. All the turbines out there were sold with the expectation of a useful life of 20 years, but they will likely need multiple replacement gearboxes during that time. Certain customers are more aware than others, and some are very concerned about it because they don’t have reliable, consistent options. That’s where we come in.”

Due to the youth of the industry, dedicated specialists have yet to fully penetrate the market and offer detailed testing and maintenance. “Customers are striving for technical information, and they just can’t get it today,” says Bruce Neumiller. “This is why we looked long and hard to get a testing solution that would provide all of the capabilities we want.”

Creating and filling a market niche

The three partners behind the fledgling company combine a serious wealth of knowledge from the fields of large gearing, power transmission, and wind energy. It is evident in the clearly logical way that they have developed the company, from careful business modelling and market needs analysis, to the location of their purpose-made facility and the tools they chose to use.

After investing a large amount of their time in pursuing the necessary funding, and succeeding in attracting millions of dollars of investment capital, they are clearly not the only ones to take their ideas so seriously either. “Our very careful industry analysis work shows that there is a clear need for an advanced company providing dedicated gearing, bearing and gearbox expertise,” says Bruce Neumiller. “And critically, one that uses the very best equipment and parts, as well as offering advanced testing capabilities.”

As dedicated specialists, Gearbox Express is set on a deliberately narrow brief. “We truly are gearbox guys,” says Bruce Neumiller. “Rather than doing other things and then fixing wind turbine gearboxes on the side, gearboxes are our entire focus.” This means concentrating solely on remanufacturing them to the best specifications, using their self-developed test stand that features “unsurpassed capabilities in the industry.”

So rather than competing with established companies and interests, Gearbox Express aims to complement them. As Bruce Neumiller says, “We don’t perform up-tower work on the installed wind turbine, so we can have a relationship with the operations and maintenance companies. We don’t manufacture gearing so we can have a good relationship with gearbox and wind turbine OEMs. And we can have a direct relationship with the turbine owners. So that’s the critical difference between us and anybody else.”

“Our business model is rooted in efficiency, quality, speed, and a passionate attitude towards excellent customer service. The sooner our customers have their gearbox up-tower and operational, the better it is for their business. And that is all we are trying to achieve,” he says. It is with this in mind that they are already establishing an exchange inventory??Bringing a novelty to the market – A carefully maintained gearbox pool

A key symptom of the developing industry ecosystem is the lack of aftermarket infrastructure such as spare parts and replacement gearboxes. This is a central aspect of Gearbox Express’s business model, and they have built a stock of new and used gearboxes including GE, Vestas, and Gamesa units.

“To our knowledge, gearbox pools don’t exist in the market yet, other than owners having spares,” says Bruce Neumiller, “and they need to be carefully maintained. You can’t just leave gearboxes lying around in a crane yard as they develop flat spots in the bearings, and get moisture inside them.” Instead, his team plans to supply gearboxes that have been carefully remanufactured and then maintained by experts with a strong interest in supplying a quality product – backed by a novel three-year warranty.

Current replacement situation

Without a clear aftermarket infrastructure, replacing worn-out gears is currently not as straightforward as in, for example, the automotive industry. There are basically two options: a rebuild by the OEM which can be costly, time-consuming and difficult to obtain, or reverse-engineering a replacement part. While the latter approach has some successful proponents, it can face quality issues.

According to Bruce Neumiller, “There is a risk using reverse-engineered gears as you don’t know where they fall in regard to the original tolerances. They could be on the high side, or on the low side, and neither do you know the original heat treat or material specifications. The risk increases even further if you mesh a reverse engineered gear with a reused or reground gear. If you have one gear on the high side, and one on the low side, you’re going to have poor performance.”

Using original OEM-gearing where possible means their warranty of three years will lead the industry, where the standard length is for one or two years. In addition, by having the OEM relationship, they will have the opportunity to improve every gearbox with all of the upgrades that will have been developed since the gearboxes were designed – meaning gearboxes will leave Gearbox Express’s premises remanufactured to the very latest design standard.

Working alongside gearbox OEMs also means that Gearbox Express faces no restrictions obtaining original gearing that competitors of OEMs – such as those that produce gearing – might face. “We have good working relationships with a lot of gearbox OEMs, and that, in effect, becomes our supply chain,” says Bruce Neumiller.

Breaking the mould

Entering the marketplace presents some challenges to the team from those who have yet to appreciate the need for their services. “It’s difficult,” says Bruce Neumiller, “we’re providing value to customers that they don’t yet fully understand that they actually need. Providing an exchange gearbox and having a one-price transaction versus a menu price or a customer-repair price model is different. But it takes lots of time out of the system as it’s much more efficient, and gives them a much better end-product.

Rather than employing a large sales force though, the team sees word of mouth and close personal relationships as the way in. Following their careful business development work they have decided to concentrate on establishing excellent relationships with fewer, loyal customers and care for them in a way that a young and agile company can do well. Building an exchange inventory covering all the major models – of which there aren’t that many – will give them a utility in the industry they believe will quickly be spread around.

When planning their test stand, the team looked very carefully into all of the options available, in a process that took over a year. “One of the reasons we approached our test stand in the way that we did, and generally contracted it ourselves rather than buying a turnkey solution, is because we needed to have a great deal of flexibility in the finished product,” says Bruce Neumiller. “Rather than only being able to do a limited series of things, ours is far more capable and flexible, by design.”

What this means in practical terms are features such as infinitely variable and full torque from the moment the test stand turns up to the motors rated speed and power. This allows them to vary torque throughout the test, induce spike loads, and generally simulate more accurately a wind turbine’s actual duty cycle. Working with the owners, they can tailor the test to the loads and speeds of each individual wind farm and turbine location. After all, since the wind blows differently in Texas than it does in Iowa, why should every portion of each load test be the same?

As Bruce Neumiller says, “With the design of our test stand, we are able to far more accurately replicate the conditions that a gearbox may see in a turbine than with a traditional production load test stand. This allows us to be able to offer a significantly longer warranty that is normally seen in the industry.”

In addition, they can test industrial gearboxes, opening potential applications for the mining, marine, paper and steel industries. Performing dynamic load testing for these industries is another unique capability that is already creating promising interest.

Setting up their test stand

With quality as their mantra, the team searched long and hard to find the many unique capabilities needed for the sophisticated testing they have planned, and Brüel & Kjær’s Production Test Advisor (PTA) solution came out on top for its easy integration with the test stand, as well as the technical expertise in vibration that Brüel & Kjær is famous for. Further, the PTA system gives excellent reporting capabilities.

“Brüel & Kjær has an excellent reputation as a global leader in test stand solutions. Aside from the technical supremacy, there is also the advantage for us as a start-up, of sending out a clear message of our commitment to quality by investing in the best equipment,” says Bruce Neumiller.

In addition to the PTA software, Brüel & Kjær supplied envelope analysis and order tracking software, FFT and CPB analysis software, time data recording software, and sound power assessment capabilities based on sound intensity techniques – all backed up with annual maintenance and support contracts.

Hardware is in the form of a 5-module LAN-XI frame including a battery module that can power the entire frame, and removable module front-panels to allow different connectors to be used. IEPE accelerometers equipped with TEDS, along with a calibrator, completed the hardware order. Finally, extensive training from Brüel & Kjær staff ensured that the solution completely fitted into Gearbox Express’s setup, and communicated with the rest of the test stand.

Future trends

The future demand looks safe for the kind of attention to detail offered by Gearbox Express. “We are really the only truly independent, third-party gearbox remanufacturer in the US market, by design, and this will become even more important going forward as the market matures and the channels consolidate, because the channels will change in the future,” says Bruce Neumiller. “We are already starting to see it,” he continues. “As turbine owners become more sophisticated, they will play a much greater role in the specifications for major component replacement.” Clearly this is good news for a company offering industry-leading quality and technical knowledge.

Where turbine owners might be used to relying on turbine OEMs or their independent service provider to make decisions on specifications and so on, they are tending to get more and more involved. “Specifying a remanufactured gearbox using OEM-produced gearing is something that never existed before, but is becoming more common,” says Bruce Neumiller. “It is becoming more common in the market, so that’s why we are coming right out with such a highly sophisticated and technical approach.”

Beginning in May 2012 with a capacity of up to 200 gearboxes per year, Gearbox Express’s envisions plenty of business to keep them working at capacity in just the neighbouring states of the Wisconsin location. Ultimately though, it is not even that important to be close to the turbines they service, as Bruce Neumiller says, “We can be anywhere in the US in the time it takes to get a crane up at the turbine’s tower.”