Comparing Replacement Components to Extend the Life of Gearboxes

Making the right decisions on the subcomponent gears and bearings in your gearbox bill of materials is critical to maximize life. However, operators, OEMs, and suppliers face uncertainty of the life extension benefits of one component versus another without heavy investment into hardware testing. This webinar recording will show how Virtual Supplier Qualification can help determine the best cost/benefit between suppliers for gearbox component replacements by leveraging High Performance Computing, multi-physics prognostic models, and simulations and data analytics.

Recording Transcription:

Natalie: Thank you all for joining us today for the comparing replacement component to extend the life of gearboxes. And welcome back to our webinars series for those of you that have been here before and thank you for joining us to those of you who are new. I wanted to take a minute to introduce myself. My name is Natalie Hills. I’m the marketing programs manager here at Sentient Science. My contact information is here on the screen. Please feel free at any point in time to reach out to me via email or my phone. I have a variety of resources that may help you, and I would be happy to send over those links directly.
Before we get started, I just want to tell you a little about our webinars series. We do host one webinar per month, three per quarter, and we always start with prognostic technology. During this session, we give a deep technology discussion on prognostic technology for our viewers to understand how it actually works. We then take them into the life extension application. And here we show them different applications and forms that our technology be applied to such as motorcraft, industrial equipments, and as well as the energy sector like we’ll go over today. Finally, we wrap it all up with the discussion on the industrial [inaudible 00:01:21]. For those of you who’ve missed some of our webinars in the past, they all are hosted on our website under our video library tab. There’s a recording and Powerpoint presentation for you to view as well. If there’s any topics that are of interest to you, please feel free to reach out to me. I’d be happy to send you direct links to all of those.In the lower right-hand corner of your screen, you should see a Go To Webinar control panel. There is a little box that says question. Please feel free to insert your questions in this box during the presentation. We’ll allow ten minutes at the end of the presentation to go over these with Wesley and Jason. If we don’t get to all those questions, I will make sure to follow with you directly at the end of the week.Before we get started, I just wanted to introduce you to Wesley Thomas. He is a business development manager here at Sentient Science. He’s in charge of the commercial customers and partners in the wind aerospace and our industrial equipment sectors. We will also be hearing from Jason Eddy today, our partner at Broadwind and I do want to thank Broadwind for joining us, I don’t think I got to say that but thank you for joining us. It’s really been exciting working with you, and we’re excited to get started. Jason served as the vice president of the Midwest region in a technical team as Broadwind services. He has joined Broadwind in 2008 and worked previously in the energy maintenance services group. At this point in time, I’m going to pass over the presentation to Wesley Thomas, and we can take him through a little bit about what Sentient does and where we came from.Wesley: Hey Natalie, thank you so much for the introduction and thank you everyone for joining us. I’m very happy to be talking about Up-Tower replacements. More and more as we talk to our customers and partners, Up-Tower Solutions are becoming more and more a part of their operations and maintenance strategies, and I’m excited to talk about this with Broadwind today. And for any of those who don’t know us here at Sentient, I want to do a very quick introduction. Our company is really based upon three core capabilities. Prognostic technologies, life extension solutions, and support for the industrial internet. And when I say, a Prognostics company, I mean multiphysics model where our material scientist and tribologist make models that dictate and understand how a gearbox is built and how it’s being operated in the field. They will be able to predict the future failures and life of those gearboxes. And we have taken these prognostic models and packaged them into life extension services where we can run what-if scenarios on the model to find out either a class of problems in design, how to best design a product to meet the [inaudible 00:04:22], or for asset management to make sure that you’re optimizing the way you’re operating and maintaining your gearboxes.

Today, we’ll be focused on Up-Tower replacements and how these life extension services work in that class of problems. And overall within the services that we provide are part of the greater industrial internet ecosystem. Today we have our models connected to over 5,000 operating assets today and we’re seeing that more and more as companies are thinking about industrial internet, big data, and diagnostic programs to track spare parts inventory and OEM optimizations. Our true prognostic approach can complement these programs to make sure that they’re getting up and running, that they’re predicting failures more accurately, and ultimately providing value faster. And what we’re going to talk about today over the next hour, Jason is going to walk through the pros and cons of Up-Tower Replacements and what challenges they’re solving in the wind industry with gearboxes. He’ll pass it back over to me, and I’ll show you some examples of how prognostics can help speed up and optimize proactive Up-Tower and Down-Tower replacement strategies and how you can use that data. We’ll be excited to show the case study at the end of the newest, hot of the press project that Broadwind and Vintage worked on together to compare a ring gear life that can be rebuilt Up-Tower. And at the end, we’ll have any questions so as we’re going through the presentation, please make this a two-way dialogue. If there’s anything that we can address, please let me know.

But at this point, I will pass it over to Jason to get us started on Up-Tower Replacements and the challenges in the wind industry.

Jason: Thank you Wesley and Natalie for the introductions and again for inviting Broadwind and myself to be on this webinar with you folks and thank you, and good afternoon to everybody out there that’s dialing in. A little bit of background on Broadwind services for those of you that may not have worked with us in the past. We are a wind service company. We’ve been in wind for over 15 years now servicing the drivetrain blade and even offering field service solutions across numerous wind platforms, dating back to the kilowatt vintage turbance. And we also have in-house gearing capabilities. We feel in our DriveMax Solutions Suite, we cover four major areas that make us a full circle or full-service provider, solutions provider within in wind. Starting with inspections and assessment capabilities, offering engineered solutions and upgrades to wind turbine drivetrains, having shop and test capabilities, and then, as I mentioned, full service field capabilities which include Up-Tower gearbox repair and rebuild. Our shop locations, we have two shops located in the Midwest corridor. One being in our Howard, South Dakota location and the other one located in Abilene, Texas. And we also are industry leaders in what we offer Up-Tower from minor repairs all the way up to complete gearbox rebuilds.

As most of you are well aware of in wind, the drivetrain, more specifically the gearbox is a very important topic when it comes to major maintenances in the wind turbine. Several of these platforms are seeing increased failure rates and certainly almost all platforms, the gearboxes are not expected to run and remain in service the entire lifespan of the wind turbine obviously making it a critical discussion point and why we’re here today. We feel that our approach and several of our customers are making a very important step in the industry. And it’s from a reactive maintenance approach to a more proactive approach to the drivetrain or the wind turbine. And this approach is yielding several benefits or risk reductions to the end-users including increased asset life, increased major component planning or budget accuracy for your maintenance needs, minimizing long-term maintenance costs. In many cases, it’s eliminating, especially with Up-Tower gearbox repairs ahead of major failures and gearbox change-outs and rebuilds in the shop setting, it’s eliminating the need for several gearbox CAPEXs. And it’s also improving cost or reducing cost in the form of limited or reduced turbine downtime, in many cases crane cost being minimized and shipping and logistic costs being decreased. And just, in general, less management costs absorbed by the customer through partnering with the service provider that can provide a turn-key solution and options around Up-Tower repair or major component change-out.

And as Wesley said, I want to run everyone through a comparison between the pros and cons, if you will, of Up-Tower rebuilds versus shop or traditional gearbox rebuilds and swap outs. The first item to walk everyone through is our first phase, if you will, of this of a major maintenance, such as gearbox repairs, the assessment. Equally important for both, in Up-Tower repair, rebuild, or a traditional gearbox rebuild and swap out, in many cases, this is the phase where the service provider and the customer end-user actually determines what the options are based on how the gearbox failed, what issues have been presented as far as abnormal oil, vibration issues or perhaps four scope inspections that have yielded signs of a failure mode within that gearbox. And so again, this first phase is very important for either option, and again it helps the customer and the service provider work out a game plan on the… which solution is best fitted for the problem.

Safety, I wanted to mention safety. Obviously, it’s paramount to any major maintenance or major instance of repair in either shop or field. However, when you compare the two options of repairing a gearbox Up-Tower in the shop, several different considerations need to be made. For example, in a shop rebuild, certainly there’s a lot of safety considerations taken around major components being installed and removed, lifting, and rigging, and spinning components. However, that’s typically in the service provider’s shop and not on the customer site and not certainly not Up-Tower. So when you move over to an Up-Tower repair, the actual gearbox rebuild goes from the service provider’s facility to actually at your site and Up-Tower where you have the element of working at heights, environmental considerations, as well as potentially more subcontractors such as crane providers and potentially more service providers.

Cost. When we compare the Up-Tower versus the shop rebuild, in most cases the cost is typically driven down in an Up-Tower repair as opposed to traditional rebuild and change-out. Some of the key things, as I mentioned in the couple slides previous, crane costs can be driven down in a couple ways. In many cases, a smaller capacity crane can be utilized which drives cost down and, in addition, the time on site for the crane in many simpler Up-Tower repairs is much less than that of a traditional swap out.

Some other considerations. Shipping costs can be driven down substantially due to the repair providers bringing the components with them to do the Up-Tower repair versus the shipping cost of sending a gearbox to site and then also the mode and d-mode of the crew that will swap it out. And additional items also is just the amount of time the turbine can be down. In many cases, when you consider the shipping time frame and coordination for traditional swap to that of the Up-Tower repair option, many times from the instance of the turbine going down on a fault or an issue to the time it’s back up in service is shorter in an Up-Tower repair scenario.

And then the other thing that can compare is time frame. And as I mentioned, typically the time on-site is less for an Up-Tower repair for any traditional swap out. Cleanliness is the next item. I wanted to go over on a separate slide. Evidently there are obviously the checkmark goes to the shop rebuild when it comes to cleanliness for several reasons. You don’t have as many environmental concerns related to cleanliness in a shop environment. As we all know, many shops have a segregated clean room for assembly and testing from their tear-down and repair areas. It’s not open to the environment such as a gearbox repair Up-Tower which is obviously in the field. What a lot of people don’t realize is the other cleanliness considerations that are more critical than that of what mother nature can dish out. You have in a shop or Up-Tower repair situation, you have within the gearbox itself all the areas where the oil flows, the galleys and small piping and reservoirs that cannot be cleaned out well. Either in a shop environment with parts washing machines or Up-Tower by wiping and cleaning a gearbox out by the technicians after disassembly. It’s very critical and important that a proper oil flush and rinse is done to any gearbox that’s rebuilt, whether it’s in a shop or Up-Tower. This allows the hot oil… flush allows the gearbox be clutched and cleaned out in several areas where a parts washer or wiping and cleaning won’t go. And then after that flush and rinse stage, it’s important that proper break-in protocol is followed during the test and spinning of that gearbox in the first hours after it’s rebuilt.

And again, this applies to either shop or Up-Tower. If it’s on the test stand in the shop or if it’s Up-Tower. Well the turbines pinwheeling for the first time under no load and then when it’s first put under load by the generator, it’s important that the flush and break-in oil is in there to help clean the gears and bearings to remove any asperities from the manufacturing process that may be on the gearing from grinding or the bearings on the races from being ground or the rolling elements. Just a couple of examples on the slide, you’re looking at. I put two pictures on here. One in the lower center is a bearing from a rebuilt gearbox and to the right, a little bit larger picture, is another bearing in the same position. It’s not the same bearing obviously, but it’s the same position on the same vintage of gearbox. I just want you to look at those two pictures. One has just been installed and had seen no run-time. And the other one has gone through a testing and wrap-up Up-Tower with the flush oil and this spot ready to be turned into production. And a lot of people would probably pick the lower center picture as the bearing that’s never seen any run-time and the one in the right hand as the bearing that’s seeing some run-time because as you look at the rolling element as I’m running my mouse across, it looks as though there’s some grooves or damage to that. That’s actually from the machining process and those are the asperities I’m talking about that have to, as the gearbox breaks in or wears in, those have to be liberated or removed, and the bearing goes through a process of polishing itself. The same thing happens with gear teeth in their mesh that removes these and they need to stay suspended in that flush oil and then either make their way out to the filter or the ones that would pass right through the filter because of how small they are will be removed when that flush or break-in oil is removed and not be present when the final fill is installed.

I just use that as an example to kind of elaborate a little bit on what I mean by asperities that need to be removed or polished off during the break-in process. And then the lower left-hand picture shows some oil canisters, some samples. The one to the left is the original oil or waste oil. You can see how old, and used, and discolored that is. And then the flush oil, which is originally the same color as the rinse and final, shows how much of that stuff is still present after disassembly and rebuild. It gets flushed out when the turbine’s running and the rinse is much cleaner, and then the final fill is obviously the color your oil should be after it’s put in turbine in a clean gearbox.

The next slide that I want to cover is testing. The shop rebuild obviously has advantages from a testing standpoint over an Up-Tower repair or rebuild. But I really want to emphasize that you can still validate an Up-Tower repair or rebuild and you can still capture a lot of data from the rebuild to prove that it was done with the correct components and the people that performed the Up-Tower repair followed the process and everything’s functioning as expected in that gearbox. Obviously in the shop environment, you have a test stand that can be used to do a full load, full speed test, and everything before that as far partial loads and partial RPMs. Up-Tower, you’re certainly more limited. You simply can only do a two-stage test. You can pinwheel the turbine without the generator online to basically do a very minimal or no load spin-test. And then once you validate that all the bearings and gears are installed and seated properly, then you have to go to a full load or put the turbine online. But again, whether it’s a shop or a Up-Tower rebuild, you can still validate the testing… validate through testing. Obviously, on the test stand you have CM data that you can capture. Bearing temps, oil analysis, and even wear patterns on the teeth if your provider blues the teeth prior to running the gearbox or during the assembly stage which I have a picture on this slide of a wear pattern, a good wear pattern on a set of teeth in a rebuilt gearbox.

Again, the same thing can happen Up-Tower. We take our portable condition monitoring equipment and get a baseline of that gearbox after it’s rebuilt that we can compare it to later and also make sure that there’s no issues with the bearings or gears from a vibration standpoint. Oil samples can be pulled and validated through lab analysis. And again, we check the wear pattern on the teeth to make sure the alignment’s good, and installation went well, and that there’s no issues with the gearing. And again, any quality service provider should have a formalized system in place to report out what was found, and what was done, and how the test went on either an shop or an Up-Tower repair. I hope that helps kind of weigh things out and explain the different steps and considerations between a shop or an Up-Tower repair or rebuild. Wes, I guess we’ll turn it back over to you now.

Natalie: Wesley, I hate to interrupt, but I can’t hear you at this point, and I’m afraid that our listeners can’t hear you as well.

Wesley: Thank you Natalie.

Natalie: No problem.

Wesley: Thank you for doing that. At this point, I want to invite our listeners to participate the call through a poll question. So now that we now the differences of the Up-Tower and Down-Tower replacement, and what’s involved in that, how would you classify your current maintenance strategies that either you, the ISP you’re working with, or the OEM, who’s working on potentially as [inaudible 00 :25:26] under warranty is using? Whether it’s run as a failure approach, which is trying to get as much out of that gearbox as you can until it’s going to fail and be replaced, schedule of maintenance in a plan with every six months, you’re doing a certain type of maintenance to keep the turbines running as long as you can. Condition based maintenance where you’re waiting to see indications of a failure such as vibration or oil debris, or inspections to plan when you’re going to do those change outs. Or a proactive, predictive maintenance where you’re using many different strategies like prognostics to get that long-term visibility and plan those in advance.

Natalie, we can close the poll and let’s see how it looks. It looks like that everyone classifying appears to be about 50% who will do run to failure and schedule of maintenance, and the remaining go into condition based maintenance and proactive approach. I know as a company, we believe in prognostics and I am biased to say for those who are working on a run to failure schedule maintenance approach, I would consider telling you, I recommend that proactive and predictive maintenance approach and as we talk about how to set-up and optimize Up-Tower and Down-Tower replacement program, that would be more clear. So thank you Natalie.

Now to get started, I just wanted to show the digital clone live of which is the software service that we provide on assets in the field today that are being monitored 24/7. And when we’re thinking about how to optimize a ONN strategy, whether you’re doing it in-house or with a third party, the first thing the model can help with is to help an operator drive down the cost it takes to assess the condition of their gearboxes. So with the prognostics models, we can see an updated ranking of how critical each turbine is in a fleet or a site. And instead of having to go and boroscope every turbine or do analysis on the oil samples, this data could help complement those programs by saying, “Why don’t you focus on the critical assets and optimize the program so you can drive down the cost it takes during the assessment but still have that data and set-up your own end strategy?” And then once we have an assessment at a fleet level, the digital clone we modeled can go down to the specific turbine and look at each specific gearbox to see where you should do Up-Tower replacements and where you should do full gearbox swaps. And within the prognostic models that are built for each turbine, we’ll understand all the critical components inside the gearbox and what their remaining useful life and failure risk are.

So therefore if you’re making a decision of what to do… Let’s say, for example, you had a high speed bearing that you see is going to fail Up-Tower. As opposed to running that until failure and having it fail in a year or two once the bearing fails, the planetary gears have failed and it could cause 400, $500,000, what if you just did a bearing replacement and it cost that proactively and spent $20,000 to get that boost for main useful life? It could also be that when we’re looking at the turbine condition today, the planetary gear set has already experienced some mechanical failure, and there is debris in the oil. And ultimately, even if you did some Up-Tower rebuild or a swap out, it wouldn’t help extend the remaining useful life to the goal that you want to do. So in those cases, you would want to choose a Down-Tower gearbox rebuild or a Down-Tower gearbox swap out. But ultimately, at this level, the prognostics is going to give you data you need to decide how to do those major component repairs. And once you have your plan set, you’ll be able to plan for inventory spares and your OPEX and CAPEX budgets for not only the year ahead but years past that.

And at this point just to looking at the last information, the poll we did, I’d like to understand for the operator that we’re working within this call, how prevalent are gearbox failures happening. Out of all the failures that you’re seeing, how often do you expect to do gearbox replacement and swap outs as opposed to doing an Up-Tower rebuild or an Up-Tower replacement? We’ll give a few moments to answer that question and Natalie when you’re ready, please close the voting, we’ll go through the results.

Natalie: All right. Thanks, Wes, I’m just going to give us a few more seconds here and then close the poll.

Wesley: Great. So it looks like the majority of our listeners are within that 0 to 25%, which is good to hear. Gearbox failures are obviously becoming more and more a problem and we want to help try to find out that perfect fit between how much you should do Up-Tower and how much you should do Down-Tower with the prognostic tools. Now as we move forward. Once you’ve already made a decision to do an Up-Tower repair or a gearbox swap, the next question is how do I know that I’m getting that done by the right supplier. And so Natalie, if we close the poll. Thank you. When we’re thinking about what to do Up-Tower, we always want to be cognizant that the operator is looking for not necessarily the longest life extension but the right amount of life extension, for the right price, at the right time. For example, if you had two bearings that you were considering to do an Up-Tower swap. Perhaps supplier A gives 18 months of additional life extension for the gearbox but supplier B would give 24 months.

Now potentially through any of the obvious goals, you would think that supplier B is absolutely the choice that you would want to go with. But consider if supplier B pushed that failure for the gearbox out by 24 months and the gearbox fails in the winter, there can be additional downtime and additional lost revenue during the high wind season. And in some places and environments like Canada, it can be very difficult to get to that gearbox and get all the equipment in place to actually do the swap out. So perhaps, in this situation, supplier A with the 18 months of life extension would be the better fit so that change out can be grouped with others in the winter. And ultimately this is like doing a test Up-Tower of all the decisions that you can make with these Up-Tower placements. So you’re making informed decisions. And for suppliers, you have the ability to show your competitive advantage and year value to the customers and get compensated on a quantified basis. Because ultimately as we’re running through prognostics, what we’re really trying to get to is the Gold [inaudible 00:33:38] program. Maximize the value of your assets and maximize the return of cash flows to the equity holders. And within prognostics and a trade-off simulation that can be run, we can evaluate multiple decisions to find the best return on investment.

Whether it’s doing an Up-Tower replacements or a gearbox swap or if you’re considering an operating package and want to see how that affects the gearbox life or load mitigation tools or techniques potentially derating, as well as doing oil changes or oil flush, with these prognostic tools, you can be proactive and see how these are going to affect your turbine life at a specific asset before you go and make those decisions. And by tying it into our life calculators that we build with our customers, we can have the same information for ONM operators and asset management professionals, so you can have control of that turbine life and be proactive in your maintenance planning. Just put your strategy together to try as down the OEM cost while still achieving your pro forma goals.

So Jason, at this point I’ll pass it over to you and what we’re going to do is show you a case study of a project that Broadwind asked Sentient to do to compare a ring gear that Broadwind had upgraded as an example of these types of upgrades that can be done and simulated within the digital clone prognostics model.

Thanks, Wesley. Before we get into the case study on what Sentient and I, what we did together, I’d like to just double back to a couple of things Wesley said and go over some of the solutions and upgrades that we offer our customers. Again, based on years of inspections, and failure mode analysis and root cause analysis to ultimately remove some of the failure modes and help ensure that the gearboxes run for more hours after they’re rebuilt. The gearbox itself, as far as upgrades go, I just want kind of get everybody on the same page here first. The way I see it, there’s really a gearbox can be categorized in the three major areas. The gearing and bearings obviously is two and then the third, and of the equal importance, is the lubrication within the gearbox. I’m going to walk through upgrades we’ve done on all three of these areas. Here we go. Getting the slides to keep up with me here. The gearing, over the years we’ve identified several issues on different platforms in different positions on gears. We’ve made a lot of changes to material. Again, based on not only failure modes but the fact that as a service provider, we’re not mass producing the gearing. We are making them in the aftermarket. To get at it, life out of the rebuild, many times a little bit added cost of material will go a long way and be well worth it for a gearbox that runs longer. We’ve in several instances, made improvements to gearing based on starting with better raw material or a different material spec. And then couple that up with potentially the need for different heat treat option due to the material changes or just again, since we’re not mass producing, spend a little more time in cause and in heat treat process which still, given that these aren’t mass produced gear sets and they’re in the aftermarket, really the impact is small on the cost side.

And then the other thing that we’ve had a lot of luck with on several platforms over the years is going through from a geometry and tooth profile standpoint, looking at how the gears mesh together, lead-in and in other items that may have been an issue or affected oil film thickness. And making some slight changes there, either on new tooling technology that’s out there for grinding the teeth or just, again, to improve from a design standpoint the way the meeting teeth interact. Related to the bearings, we’ve been working for years with the bearing OEMs on several root cause analysis that we’ve seen and issues that we’ve seen to not only help validate upgraded bearing solutions but also in some instances, even work through the cause of the issues and then therefore what needs to be done to improve it. Again for years, even though we do not manufacture bearings, we have tight relationships with several bearing OEMs and actively engage with them on what’s the next technological advance out there that is just going to ultimately or potentially result in extended bearing and gearbox life.

And then lastly in the lubrication front, we are certainly not oil manufacturers and or seasoned tribologists but we’ve worked closely with the oil OEMs over the years in oil change procedures and practices. And certainly understand, as I mentioned earlier, in detail how important it is to keep the gearboxes clean and properly flush and break-in gearboxes using the right oil packages and quite frequently pair that up with our gearbox repair offering and work with the end-users around oil and cleanliness issues in the gearboxes. And then over the years, we’ve also worked closely with several other folks for that supply components to the lubrication systems. And worked with improvements around everything from heat exchangers to plumbing components and even seal upgrades that help keep contamination out.

As Wesley said, a few months ago or almost a year ago now I should say, we identified that although we have a lot of data and a lot of inspections that we have done, and a lot of root causes, and a lot of upgrades we’ve put together, we really felt the next step for us was to partner with somebody that could get beyond the surface and failure modes with us and really validate improvements we’ve made from an in-depth metallurgical analysis. And then also see where we can take this as we partner with them going forward to even offer more improvements and upgrades to different gearboxes on several platforms. What we decided to do was there is a… on a particular common platform out there in the wind industry, there is a gearbox with the compound planetary that had a known failure mode that we verified as well early on in its existence, post warranty, in the ring gear. And we thought that would be ideal candidate to provide Sentient, in great detail, what we found and did to change the spec for that ring gear and have them compare it to the OEM spec and even a couple other specs that we believe are out there used by others. And basically have them do a third party metallurgical analysis and report out to us. That’s the case study that Wesley was referring to and that I think you’re going to walk through a little further the results of that with our folks on the line.

Wesley: Great. Thanks Jason for the intro. As Jason mentioned, when Broadwind reached out to us and requested to do this validation study, on the design side, we do these types of projects very often. Where we would take different configurations of a gear, a ring gear in this case, but also bearings and full gearboxes. And we build the detailed digital clone models that take account the different specs on the geometry and micro geometry, the material microstructure, the surface finish, asperities, all the way down for the lubrication. And in this process, we went and actually cut up some pieces of these materials to make sure that we had the exact digital representation of that gear in the three spec that we could then run through simulations on the computer. With this type of prognostics IP, instead of being able to test one prototype here and get one data point, once we have the models built, we can run multiple simulations against multiple duty cycles. And we put together a duty cycle with Broadwind to an apples to apples comparison of the three spec. The results came back and we can see here on the right when we compared the three different ring gears specs over the full load cycle that we ran and did an apples to apples comparison, the first simulation came to L-50 of 4.72 years. The secondary ring gear spec came to a life of 14.93 years which is three and a half times spec number one. And the Drivemax upgrades that Broadwind has assets to validate came to an 8 times life improvement at a 37.84 year in L-50. So what in this information meant once it came out of a models was if you had seen a gear failure on one of these ring gears in the field after three years, obviously every turbine is going to have a different load spectrum that it’s being operated under.

But if you had changed this spec on that gear… So maybe you did an Up-Tower replacement or switch it out, now you can get from that three-year to a 24 year mark with the 43-40 Drivemax spec and maybe get past that even a 25 year life on your future pro forma without having to do another ring gear upgrade. As a third party, this is a type of work that we do to help them validate these types of improvements that otherwise you couldn’t see data from for years and years in the future.

And ultimately, where this brings us to is where do we go from here? If you’re a company that’s making an upgraded gearbox like Broadwind or your doing comparisons of different components inside your current design, what prognostics really means is we can investigate so many more design options that would not have been considered before because it would have taken so much time to validate and test all those considerations. One example that we’ve came across was the field that we’re seeing in the wind turbine gearboxes is that just several decades years old and new advanced steels are coming into the market right now. The example I have one the screen is that Ferrium C61 and C64 advanced steels that are currently being adopted in the aerospace industry as well as the F-1 at NASCAR racing industry to increase component life and decrease power density. What’s the capability of modeling means is if a customer, whether it was an operator or a designer, wanted to reconfigure a gear set and see what these new types of advanced steels would look like in a gearbox. We can run those with prognostics models, so they have the data before they go and make the decision. And whether this is materials or new surface finishes, new load mitigation tools, these types of competitive advantage can be proven much more cost effectively and much more quickly to seeing help validate if those designs are working and optimize to get that right life, at the right time, at the right cost.

That really brings us to the summary of our presentation today. Once again, thank you so much everyone for joining us. I think it’s a really important conversation to have on Up-Tower bearing replacements and proactive maintenance approaches. And to just leave us with a summary, what Sentient allows customers to do is simulate the gearbox remaining useful life before and after you make Up-Tower or a gearbox swap out for operating assets. And we do that with prognostic models. Because sometimes there are scenarios where a gearbox will not have the expected extended life that you want for it to have to meet your goals. And you want to make sure that you know this before you go into a decision and lock in to get work done. Even at the assessment level, when you’re trying to look at all of the different ways that you can assess the end of life of a turbine, from boroscoping and other approaches, prognostics can create a prioritized list of those gearboxes to make sure that you are optimizing that assessment program and focusing on those gearboxes that are most important. When we’re in a design space, either reconfiguring a gear box, or as putting out a new product, we can validate the life of these existing designs or new designs computationally without the investment and time to market that would take under a traditional approach of testing and validation.

I’d like to thank you all for joining. Please check with Broadwind directly for Up-Tower component replacement options and services. If we have any questions at this point, Natalie, I’ll pass it to you in case. And I would be happy to answer.

Natalie: Great. Thank you, Wes. And thanks for taking us through that. Jason, it was a great presentation and again, we were really happy to have you here today. I do have a lot of questions, and it seems like we’re running short on time so I will follow up with everybody directly after this presentation. I just want to get started here. The first question is, “Have you taken a look at supplier bearing trade-off to identify who are the best for certain locations and gearboxes?” And Jason and Wes, if you just want to jump in there.

Wesley: I’ll take that question first. Bearings is an area where Sentient came out of our prognostic research. We’re very often asked to do bearing comparisons, either for different designers or in the field to compare all the different options that a bearing could have in terms of heat treatment, of material, the surface finish and quantify those benefits. So yes, bearings are a very hot topic and are commonly asked from us. And if you send me the person who asked this question, we have many case studies on our bearing comparison work that are available on the webinar videos as well.

Natalie: Great, Wes. I’ll do that. All right. And then the next question here I have is, “Have you looked at Superfinish as a life extension action?”

Wesley: Yes. Since our work came out of the aerospace industry which has been adopting Superfinish technique for many years and validating it in rotorcraft and other areas. Superfinish is one of the trade-offs that we have done a lot of work on spiral bevel gears, for example, in the aerospace industry. And if someone who is designing a new gear set or a gearbox who wants to include Superfinish, that’s one of those trade-offs that they can run computationally to see and quantify the benefits.

Natalie: Thanks, Wes, again. I’m going to wrap it up here with two final questions and then I will follow up with everybody. “How much longer does an Up-Tower rebuild, on-site with a crane take than a traditional swap?” And Jason I think it would be best if you cover this.

Jason: Sure. Thanks. I have to lead into the answer on this by saying typically because, as everybody’s probably aware, on different platforms and certainly depending on what the scope is, it’s needed Up-Tower, the time frame can change from a high-speed bearing or a high-speed bearing and pinion change that could be done in a day with a couple of folks to a complete gearbox rebuild Up-Tower. But even in the largest scope example, for an Up-Tower rebuild of the gearbox, the crane time is almost the same as a traditional swap, especially if the rotor would need to be dropped from the traditional swap. I know a lot of customers tend to compare their costs on an on-site major maintenance in two categories, the cost they have with the service crew there working without crane and then the actual crane time. And the dollar amounts that could add it to the crane time in addition to the crew.

But as we’ve honed in on our processes and efficiencies to do Up-Tower gearbox rebuilds, we typically see the crane work lasting two full days, without any weather delays. As opposed to a swap, which is day to two days. And then obviously as I’ve mentioned with the extra validation we need to do for the rebuild happening Up-Tower, there’s an extra day or two after crane work concludes to finish up installing the ancillary components and then ramping up the gearbox and doing the flushing it out and validating that everything was done properly. So all and all, crane time is very close to the same, and you have an extra day or two of prep and validation and time on the Up-Tower rebuild.

Natalie: Great Jason, thank you. I got a more general question from the audience about the slides and if they’re available after the presentation. Yes, we do repeat them all on our website under the video library tab. We have a variety of slides and recordings from last year as well. So please feel free to go on there. Type in your name and you’re able to get access to those. Also, I’m happy to send a direct link, and I will do that after the webinar to everyone as well. One more question here I have, “Where on a gearbox do you install the accelerometer to measure the vibration?” And Wes, I’m going to pass it over to you.

Wesley: Great. So that’s a good question on condition based maintenance. I think it’s an opportunity to differentiate our model-based prognostics approach, and condition based maintenance approaches that you see in the field and how each complements each other. Where our model and our team uses those models is by knowing how a gearbox is built and we build a multiphysics model, the input data to predict the future failure risk is actually from the [inaudible 00:56:13] system itself and [inaudible 00:56:17] or other ways to quantify the wind speed. So, by understanding how the loads are operating under that turbine, from each turbine, we can run that through the gearbox and the material models to predict future life. Now, condition based approaches that would require accelerometers, where that works in the life-cycle is near the end of life. Once a bearing has a [inaudible 00:56:45] or a gear has started to crack; you’re going to start seeing vibrations in the signal. And as those get more dramatic, you could pick those out and understand that something is going wrong in that gearbox. So if you’re thinking about how those complement each other, our prognostic models can predict the long-term future life. And then as they get closer to it, the end of life, accelerometers whether they’re from us or third party partners that we’re working with, those will fuse with our models in a process called model-data fusion to manage that end of life and manage that death of the turbine. And again, there’s a lot of information about that process and the technology behind it on our website. I’d be more than happy to direct anyone who’s looking to be educated on how those two sides complement each other.

Natalie: Great. Thank you, Wes. And it looks like we are just about coming up in the hour here. I don’t want to take up anybody’s time. I just wanted to say thank you to everybody for attending. I want to welcome you back next month. We are hosting our next webinar with the industrial internet consortium. [inaudible 00:58:01] will be joining us as well as [inaudible 00:58:04] from Sentient. I will send out an invitation for that. Please feel free to register. It is on March 11th. And thank you all for joining us again. I will send out the recording for you.

Presenter

Presenter Jason Eddy
Vice President Midwest Region - BroadWind

Jason serves as vice president of the Midwest region and technical team at Broadwind Services. He joined Broadwind (previously Energy Maintenance Services) in 2008. Prior to this, Jason held positions of increasing responsibility in engineering and project management in the heavy equipment and engineered composite components industries. He holds a Bachelor of Science degree in Industrial Technology Management from the University of Wisconsin Platteville and is a Six Sigma Green Belt.