Unigear Industries in Montreal is capable of large custom gears.

David Brown, a manufacturer of industrial gearing and support services, says it has acquired Montreal based industrial gear manufacturer Unigear Industries Inc. Unigear is a privately held business known for its high quality gears. With its flexibility, innovation, quality, and performance it has an excellent reputation for customer responsiveness and a high standard of customer service in the North American gearing market.

David Brown (DB) already has a presence in key markets in North America, such as mining, and oil and gas, as well as through its premier double-enveloping worm gearing business Cone Drive, based in Traverse City, Michigan. The acquisition of Unigear and its industrial gear manufacturing and service capability is a key part of DB’s global and North American growth strategy. The business will be brought under the DB umbrella and will trade under the name: Unigear – a David Brown Company. The Unigear team, including President Ron Mehra and VP Peter Zurcher, will remain with the company and play key leadership roles going forward.

The parent company says it has a vision for the future and a defined growth strategy developed around expanding in key global markets including mining, oil and gas, conventional power, rail, and renewable energy such as solar, wind, and hydro. The acquisition of Unigear provides DB with wider access to many of these strategic industry segments coupled with local capability to manufacture and service industrial gear products for the North American market.

DB says expanding its aftermarket service offering is integral to its strategy to provide customers with locally employed specialist teams delivering world-class service. As well as becoming a North American manufacturing center of excellence, the company will also establish a service center at its Montreal facility to support customers in Canada. Additionally, the business is planning further expansion through the opening of a service center in the mining region of Kentucky, with near term plans for the establishment of additional service centers in strategic locations across North America.

David Brown
www.Davidbrown.com

Windpower Engineering & Development

By: N.K. Chinnusamy, President of Excel Gear Inc.

Gearboxes designed to acceptable and proven industrial standards can fail in wind turbine applications for reasons not fully understood. One reason could be the automated stopping and re-starting of the generator, which results in torque that far exceeds the levels of maximum rated power.

Wind-turbine applications require developing experimental and analytical tools along with instrumentation to fully understand the machine’s operational characteristics. Recent generations of wind turbines use condition-monitoring systems capable of measuring input and transient peak torques, along with the radial and axial movement of bearings and shafts to detect the onset of in-service failures before they occur.

Generating gear loads 
Wind turbine gearboxes connect a relatively low-speed rotor to a high-speed generator. Synchronous generators must run at synchronous speed, while induction generators run slightly above that (e.g. 105% of synchronous speed but that depends on load). For 60-Hz power, synchronous speed is found by dividing 3,600 by half the number of electrical poles in the generator. Synchronous speeds can be 3,600, 1,800, 1,200 rpm and so on. Rotor speed depends upon its diameter, typically 10 to 20 rpm. This combination requires a large speed-up ratio. Gear boxes for 60-cycle power with large speed-up ratios are complex in design and require epicyclic (planetary) gear sets. Planetary gear boxes have multiple meshes, speeds, and a complex power flow.

A varying wind speed and turbulence place loads on the input shaft in addition to the torque that all prime movers exert. The blades are long compared to the length of input shaft. In addition, they operate in the boundary layer so wind speed is higher at the top of the rotor sweep compared to the bottom. And then each blade tip generates a vortex which increases turbulence for downwind units.

The design of the rotor, hub, and main shaft is of utmost importance for the stability of the rotor. Varying wind speeds and turbulence produce moments on the end of the input shaft which cause shaft deflection and loads on bearings. If these effects can be isolated from the gearbox input shaft, then they do not impact the gearbox design. When the effects are not isolated, care must be taken so gear meshes are not misaligned.

Load equalization in planetary gears must be addressed for long gear life. The planet carrier must accommodate the centering force of the planet gears. Mesh frequencies must be set to prevent exciting resonant frequencies.

To make matters worse, wind-turbine gear boxes must work in extreme cold or hot temperatures. This requirement makes it difficult to find an ideal lubricant. Lubrication of bearings and gears is somewhat difficult in epicyclic gear boxes and care must be taken to assure that all bearings and gears are adequately lubricated under all temperature conditions. Cleanliness and the proper amount of lubrication are critical for the life of the components. During run-in on a test rig, cleanliness of lubrication must be checked periodically and proper lubricant flow must be established at low-speed running. Only then should final tests be run at full load and speed.

What went wrong? The broken gear comes from a three-stage industrial planetary gear box. The gear, made of 4320 carburized and hardened steel, failed at about 150 hours. Defective heat treatment was first suspected, but visual inspection revealed gear tooth surfaces like new and no evidence of defects, indentation, or overload. The gear runs on bronze bushing and its bore finish was rough with small cracks. But how deep? Metallurgical evaluation confirmed that gear tooth hardness and case depth were to spec but hardness in the bore was low. The failure was attributed to insufficient lubrication–the bronze bushing was almost friction welded to the gear. The cracks were deep, almost extending to the root. Essentially, the gear was falling to pieces.

Most gear failures will be the result of fatigue, which can be either surface or bending fatigue. However, tooth breakage can occur due to misalignment or deflection under load. Gears may fail due to defective material or heat treatment, cracks in hardening, gear grinding, or any combination of these. Pitting or scoring may also cause gear failure. Premature bearing failure accelerates the gear failure even when gears are correctly designed and manufactured.

Because gearboxes are located in nacelles 60 to 100 m off the ground, maintenance and repairs are difficult and expensive. Even routine maintenance is time-consuming. This means there is a high premium on long life and reliability.

The growth of the wind-turbine industry is creating technological developments focused on the manufacturing larger, more precise, and optimized gearing. The need for better performance, quieter operation, and higher efficiency means the primary goal is to limit losses and control other factors that reduce efficiency.

Because of the number of units that will be manufactured and installed, there is need for longer life and higher efficiency. One way to achieve longer life and higher efficiency is to develop new technology and computer tools that optimize gear geometry. Examples of technological development are improved finish with REM technology and electro-polishing. These technologies, which are used in automobile racing, are having significant, positive impacts in gearing.

In building a wind-turbine gearbox, it is also important to establish the correct bearing clearances, preloads, and proper gearbox operating temperatures critical to long life. Sophisticated measuring techniques with bearing-inspection gauges are necessary to ensure these results. Verification of gearbox performance through computerized analysis and testing is a crucial step to ensuring long life. The critical factor here, as with all similar power transmission applications, is that the gears are properly designed and manufactured. Other mechanical components that make up the assembly, along with the gearing, must be applied and designed so the overall system performance does not suffer shortcomings that could affect the unit’s performance and life.

Most gear failures will be the result of fatigue, a condition dependent on the force on the tooth and the number of tooth-load cycles. If a tooth has more than one load cycle per revolution, this must be taken into account when calculating life. Although life is usually stated in hours, it is the number of load cycles that is important. For example, if a pinion drives two gears, its life will be one half that of the pinion driving one gear (assuming the same torque on both gears).

Preliminary planetary design
Recent software can assist with gearbox design and analyses. One such program, Excel-lent, includes a table of commonly used gear materials with values from AGMA standards. If a special material is used, it can be added to the table. Also, if a higher-grade material is used, material values can be changed to reflect the new material.

Planetary gearboxes have multiple meshes and speeds, and complex power flows. This requires determining the number of stress cycles and torque for each gear. Planetary design can be evaluated using, for example, calculations from (gear researchers) Merritt chapter 11 or Buckingham page 129. The software mentioned calculates life based on a mesh of a single pair of gears. The software converts between life and stress cycles with:

C_s = 60Lω
where C_s = Stress cycles; L = life, hours; ω and ω = speed, rpm.

The Excel Gear staff performs a static backlash and compliance test. In it, the output shaft is locked and bi-directional torque is applied to the input shaft. An encoder measure rotation of the input shaft. Software plots rotation vs. torque, a hysteresis curve that allows determining torsional stiffness and backlash.

If a sun gear has three planets, the load input to the mesh calculation is 1/3 the total load. The actual life is also one-third the calculated life. For example, if the total power to a simple three-planet stage is 90-kW, the mesh power is about 30 kW. If the calculation shows a 300,000-hour life for the sun gear, the true sun gear life is 100,000 hr.

The reduction in load on the teeth in the mesh has a larger effect than the increased number of gear tooth load cycles. Consequently, the result of having three planets is much longer life.

For example, consider a simple planetary system consisting of a fixed internal gear with 72 teeth and an input shaft carrying three planet gears with 27 teeth driving a sun gear with 18 teeth. Following the calculations in Buckingham’s text, we get values in the table below.

The equivalent speed for calculating life is obtained by dividing the pitch-line velocity by the gear pitch circumference. The life obtained is for the given input speed. Using these values will give the life for an input speed of 100 rpm.

Notice that the power in the two planet gear meshes (PA and PS in the table) are less than the transmitted power, PT. Power in planetary meshes can be lower, as shown here, or much higher. When the power is higher, it referred to as circulating power.

A planetary box will ordinarily have three planets. In this case the table would be reflected in Value that change for a gearbox.

The input screen for gear design software Excel-ent shows a few values to consider.

With the speeds and loads determined, we proceed to the gear design. The planet gears are reverse loaded on every cycle. This means that 70% of the bending-fatigue strength should be used in the calculations. The easiest way to do this is with a new material. For example, if we plan to use 4140, add a new material with a name such as “4140 70% Bending”. Only the bending-fatigue value is changed for reverse loaded gears. All other values remain the same. Inputs to the design program would then be as they appear in the input screen.

The design program uses approximate methods so there is only one material specification for both gears. Note that the safety factor selected is “Wind Turbine and Critical Apps”. This uses a safety factor of 1.56 in calculation instead of the standard 1.0.

Data is then transferred to the analysis section, also part of the design software. The analysis program allows selecting different materials for the two gears. Note that the special material titled “4140 70% Bending” has been selected for the planet gear. Also, the Profile shifts have been set to zero. Profile shifts may be used in planetary gearboxes but they must be picked considering all three gears – sun, planet, and ring. For preliminary designs, using a zero value is best.

The analysis screen for Excel-ent tells a little about the proposed gear design.

Examining the data in the analysis section reveals a power capacity slightly low for sun-gear surface fatigue. This can be changed by increasing the face width to 90-mm or by changing the material to one with a higher surface-fatigue value. Ease in making such changes allows for checking many combinations.

Designing an epicyclic gear train, especially a compound one with an overall ratio of about 80:1, is typically a complex task. Many kinematically correct solutions will not work because of excess circulating power. Using software such as Excel-lent for load and life calculations can take a large amount of time off the task because non-feasible solutions are eliminated early.

When a designer selects three planets, care must be taken so that the sun and internal gears are coaxial. The three planets have a strong centering effect. If the sun and internal gears are not coaxial, a large load may be transferred to the bearings. In that case, both the bearings and the gears may fail prematurely.

A third software section provides design and manufacturing data. The software mentioned, for example, includes an option for calculating correction factors for balancing beam strength or specific sliding, a requirement for wind-turbine gear boxes.

Gearbox design is a complex, iterative process. The three programs in the Excel-lent software package can greatly reduce the time needed to process repetitive calculations. WPE

Windpower Engineering & Development

Wind turbine gearbox -Winergy

The design of a wind turbine gearbox is challenging due to the loading and environmental conditions in which the gearbox must operate. Torque from the rotor generates power, but the turbine rotor also applies large moments and forces to the wind-turbine drivetrain. It is important to ensure that the drivetrain effectively isolates the gearbox, or to ensure that the gearbox is designed to support these loads, otherwise internal gearbox components can become severely misaligned. This can lead to stress concentrations and failures.

Wind-turbine drivetrains undergo severe transient loading during start-ups, shut-downs, emergency stops, and during grid connections. Load cases that result in torque reversals may be particularly damaging to bearings, as rollers may be skidding during the sudden relocation of the loaded zone. Seals and lubrication systems must work reliably over a wide temperature variation to prevent the ingress of dirt and moisture, and perform effectively at all rotational speeds in the gearbox.

Gear and bearing fatigue standards by AGMA and ISO are used for design, these only capture a subset of the potential failure modes of the components. For instance, the ISO 6336 gear standard provides an established method for calculating resistance to subsurface contact failure and for tooth root breakage. The standards are doing their job, but these are not the most common failure modes observed in windturbine gearboxes. More common causes of failure are manufacturing errors such as grind temper or material inclusions, surface related problems, such as scuffing or micropitting, and fretting problems from small vibratory motions, such as may occur when a machine is parked. Scuffing is adhesive wear and subsequent detachment and transfer of particles from one or both of the meshing teeth (ref ISO13989-1). It can happen quickly and is generally considered to be associated with an absence or breakdown of the lubricant film under high loads (ISO 13989-2). Micropitting is a surface fatigue resulting from generation or numerous surface cracks, and is associated with insufficient film thickness (ISO 15144-1). Film thickness is affected by sliding speed, load, temperature, surface roughness, and chemical composition of the lubricant.

Many wind-turbine gearboxes have also suffered from fundamental design issues such as ineffective interference fits that result in unintended motion and wear, ineffectiveness of internal lubrication paths and problems with sealing. Improving the resistance of future gearbox designs to all these issues is a key for the future cost of energy generated by wind turbines.

Windpower Engineering & Development

Vela Gear Systems says it will have the capability to model and manufacturer gears for wind turbines.

Vela Gear Systems says it will be the cornerstone of Marion’s Green Technology Park, a newly formed cluster of sustainable businesses, comprised of three private companies and a business incubator. The real estate component of this opportunity is that the flagship business of this Green Tech Park, Vela Gear Systems (VGS) owns the 55-acre property and has been provided with $114 million in Economic Development Bonds from the city of Marion Indiana, and was awarded $11 million in federal tax credits by the U.S. Dept of Energy.

The intent is to develop the property, building four modern facilities, as a cluster of Renewable Energy focused businesses. Vela Gear Systems seeks a financial partner to credit enhance some portion of the $114 million in bonds, so the site can be developed using the bonds. VGS is a manufacturer of drive components focused on Wind Energy. This is a purpose-built U.S. manufacturer of future offshore and land-based wind-turbine drives, with diversification into mining and rail. Read an article on the founder here.

The company has an experienced team from this market, and will have operations generating revenue manufacturing large drive components and gearboxes for the petroleum industry.

Marion Indiana's Green Tech Park

GenAgain, the second company to lease a facility on this property, is a renewable business that will recycle plastic refuse from this region into a high-grade oil. GenAgain will install a proprietary processing facility, and will have pre-sales of their product prior to construction of their facility. GenAgain’s processes require heated air, which will be provided from the waste heat from VGS’ processes.

Green Energy Transport (GET), a third company to lease a facility on this property, is partnered with a Korean electric-car company. GET will import subassemblies for final assembly of an electric car, targeting utility fleet-vehicle markets. The advantage of targeting fleet vehicles, such as municipal and short range urban delivery vehicles, is that they do not require public charging stations because they return at night to a home facility for recharging. The GET team is experienced in the automotive-dealership market and will have pre-sales in place prior to construction of their facility.

The fourth to lease a facility on this property will be a “business incubator,” funded by Purdue University and local colleges. In addition, the site will have a multi-megawatt wind turbine to provide power for the businesses. Each modern building will have solar panels and use the latest ideas in sustainability. VGS says the property will be a world-class example of profitable, sustainable businesses, in a clustered development including learning institutions where there are m synergies.

Vela Gear Systems
velagear.com

Windpower Engineering & Development

JLM Systems Ltd. 

Windpower Engineering & Development

Gearbox Express expects to officially open its doors in early 2012 and eventually hire 100 people.

Three power transmission and wind energy veterans have banded together to create Gearbox Express, an independent business focusing on the repair and remanufacturing of wind-turbine gearboxes. Founding partners Bruce Neumiller, CEO, Brian Hastings, CFO, and Brian Halverson, COO, have a combined 40 years of experience in the gearbox manufacturing and remanufacturing business. The team founded Gearbox Express (GBX) in an effort to better serve wind, as well as industrial gearbox segments. “Our team knows the industry and is dedicated to its success,” said Neumiller. “We see big opportunity participating in the development of the wind aftermarket as the infrastructure develops. Wind is a relatively young industry – young and growing. Much like how an entire industry was born around the service and maintenance of automobiles, we’re excited to be a part of keeping megawatt class wind turbines running efficiently during their lifespan.”  

The company is focused on down-tower services and will be one of the first in the United States to remanufacture wind turbine gearboxes in an exchange-inventory model. Its mission, that is, ensure a quick turn and get the gearbox back uptower. That means it will keep a stock of remanufactured gearboxes ready to exchange. “Our business model is rooted in efficiency, quality, speed and an attitude towards excellent customer service. The sooner our customers have their gearbox uptower and operational, the better it is for their business,” said Neumiller. He added, “We are building our shop with our business model in our sites; it is designed with high attention to detail to ensure we are creating the right quality environment.”

The company recently signed a lease on a 43,164 ft2 industrial building in Mukwonago, Wisc. The formerly distressed building was purchased out of receivership by Sara Investment Real Estate, Madison, WI, and will be leased back to GBX. Build-out of the site is currently underway. “We selected Mukwonago due to its close proximity to I-43,” says Neumiller. “What’s more, the established broad labor pool of southeastern Wisconsin and access to upcoming graduates from technical schools that are developing wind curriculums is exciting.” The company received funding from the State Energy Program (SEP) that was created with Recovery Act Funds, an SBA guaranteed loan from Investors Bank, and monies from private individual investors as well as Angel investors. It closed its minimum funding this past May.

As it looks toward its opening in 2012, GBX is committed to creating 100 jobs within the state. “The monetary support Gearbox Express received in the form of SEP funding translates into more clean energy jobs in our state and a much needed service to the existing wind energy sector in our region,” said Paul Jadin, CEO of the Wisconsin Economic Development Corporation, which administers the SEP.

Gearbox Express
http://www.gearboxexpress.com

Windpower Engineering & Development

Industrial engineering group Clyde Blowers has agreed to acquire the wind gear manufacturer Moventas Wind Ltd.

Industrial engineering group Clyde Blowers has agreed to acquire the wind gear manufacturer Moventas Wind Ltd and the industrial gear manufacturer Moventas Santasalo Ltd. Following the acquisition of the Moventas companies, Clyde Blowers, with its existing David Brown Gear Systems, will be one of the largest gear manufacturing groups in the world.

Clyde Blowers, a U.K. based industrial engineering group, covers a range of industrial engineering activities in the power (renewable energy, conventional, and nuclear), oil & gas, mining and minerals, and other industrial markets. The firm carries out activities across the world with a focus on growing them in fast developing regions such as India, China, and South America. Clyde Blowers knows the global gearing business well because its David Brown Gear Systems manufactures industrial gear and drive systems. 

Moventas operates state-of-the-art manufacturing and test facilities and has an extensive product range. It is an independent player in the global wind-turbine gearbox and drive market with products extending across a wide range of wind turbines. The company also has a strong product offering for a wide range of industrial markets and says it is well positioned for future growth.

New and long-term ownership has been sought for Moventas companies since June 2011 when after prolonged financing negotiations, the holding company Moventas Ltd filed for bankruptcy and its operative subsidiaries applied for corporate restructuring. Moventas, however, has made significant investments in its gear production from 2007 through 2008, encouraged by strong demand. But the post finance crisis markets have not supported the investments, and along with its competition Moventas has suffered from excess capacity.

As part of its corporate restructuring, Moventas is exploring possibilities of reorganizing its production in Finland. Therefore, both Finnish Moventas companies started co-operation negotiations on 21 November, 2011.

To ensure the core operations of gear production can remain in Finland, reorganizing and downscaling are necessary regardless of the acquisition. “We have world-leading companies as our customers, high engineering know-how, and quality products, but excess capacity heavily strained our financial status, leaving us loss-making. Implementation of the corporate restructuring program offers us an excellent starting point for future success,” says Moventas CEO Jukka Jäämaa.

Based on the sales and purchase agreement recently signed, the objective is to close the acquisition before the year-end. The business has been acquired for 100 million euros, and has been solely financed by equity investment.

Moventas
www.moventas.com

Windpower Engineering & Development

You might think the U.S. has lots of gear-making capacity, so why would a start-up envision a factory capable of more of the same? The answer lies in the size of the gears planned by Vela Gear Systems CEO Noel Davis. Gears required in the wind industry can be in excess of 6 ft in diameter, while gearboxes weigh up to 20 tons. In addition, the nation has more than 30,000 utility grade wind turbines, where every year more approach the end of their warrantees and some near retirement. This means many may need gearbox repairs or replacements.

Davis and his colleagues are well acquainted with wind turbine gearboxes. He ticks off the types that will need repair and possibly replacement: “A planetary gearbox for a typical 200-ft high 1.5-MW wind turbine weighs more than 15 tons. Its sun gear has about a 24-in. diameter and 5-ft length, three planet gears each with about a 30-in. diameter. The ring gear has about a 70-in. diameter while spur or helical gear easily have 40-in. diameters. The output pinion driving the generator can weigh a hundred pounds. There are also smaller gear drives that pitch the three blades to catch the wind, and azimuth drives to rotate the entire 100-ton nacelle to face the wind.” None of these large slewing rings and gearboxes are small enough to be handled at the more frequently encountered automotive gear facilities.”

What’s more, says Davis, main-drive gearboxes have individual components that may weigh up to 10,000 lb, and when assembled, 20 tons. These components cannot be lifted by hand and require lifting equipment and an overhead clearance beyond what is available in most automotive-component facilities. Lifting large components, such as 6-ft diameter gears in and out of machine tools, then assembling them into a 20-ton gearbox, and then onto a flatbed truck for transport, requires a taller gantry cranes than those at most facilities. And the next generation wind turbines are just getting bigger. In the end, Davis sees a purpose-built facility just for wind-turbine gears.

Noel Davis

But where to build? Davis starts sketching a Venn diagram with three circles in North America: the location of wind farms, the location of raw material, and the location of the skilled labor. “Wind farms are mostly in the middle of the Midwest. Steel comes mostly from the areas spanning Milwaukee to Pittsburgh, and skilled machinists needed for this business are found in automotive manufacturing states. These three circles intersectd in Indiana, an ideal location for this business,” he says. Marion, Indiana to be specific.

Davis also has ideas for financing this ambitious venture. “I have some money from the sale of a previous company that I have put up. The Chamber of Commerce for Marion has also secured a hundred million dollars in bonds. But those convert only if we can drum up enough business to fund the debt of the bonds.”

He figures that his skilled workers will earn $23 per hour with a fully burdened rate of $40 per hour, while Europeans are importing this product at $60 per hour plus ad extra 15% of the total cost for ocean freight and logistics to North American wind farms from European manufacturing sites. Bottom line is that a promise from OEMs to build about 20 gearboxes each year will be the minimum needed to secure the bonds. Soon after that, Davis sees groundbreaking on the new factory, laying the foundation, ordering the machine tools, and hiring the staff.

Washington is fond of patting itself on the back for its gutsy calls, that in hindsight, are not terribly difficult. Building a new factory in American is the real gutsy call.

WPE

Windpower Engineering & Development

The input window for the design portion of Excel-Lent Gear software.

Gear and gearbox manufacturer Excel has developed software that the company says quickly determines maximum product parameters for gears needed in various industries. The Excel-Lent software is said to save engineers a lot of time when designing pinion and gear or a gearbox.

With minimal input the Design portion of the software will calculate the number of teeth in the pinion and gear, DP or Module, face width etc. required to transmit the power, within a few seconds. The calculated data can be exported to the “Analysis” section for complete analysis with clicking the “Transfer Data “ tab on screen. Calculated capacity will be very close to the required power.

Also, the company says the Excel-Lent software’s dimensioning program is versatile. Non-standard center distance or matching a new gear to an existing gear can be done by clicking the indicated option. The material tables provided have all the commercially available materials listed, with heat treat and mechanical properties to allow the user to choose any gear material from the list to fit their need.

The analyze screen from the software.

“Although commercial software has long been available in the gear industry, it has been too expensive or too complicated to be used by engineers without specialized gear design knowledge, ” says Excel president N.K. Chinnusamy. “The software is specifically designed with a user-friendly interactive input screen providing defaults and options in accordance with the AGMA 2001 standard (American Gear Manufacturers Association).” The users of Excel-Lent software can easily navigate through the input screens to edit, analyze and produce reports on the optimum gear and gearbox design for various industrial and other applications.

The analyze screen from the software.

He continues that the software is not designed for any specific industry. It can be used for machine tools, heavy materials handling equipment or even the wind turbine industry. For the wind turbine industry, for example, the designer needs a full understanding of all the operating loads on the gear members to arrive at the required power rating.

The key calculations performed are the AGMA power rating and load calculations, including bending strength geometry

factor (J) and pitting resistance geometry factors (I). Output from the software is a single page of data printed in a format that is easy to read and interpret. Other commercial software typically prints five or six pages of information, which may be confusing to most design engineers unless they are gear experts, according to Chinnusamy.

The company says that users of Excel-Lent need not be familiar with AGMA standards to use the software. Those who are not gear engineers can also benefit from the gear engineering knowledge embedded in the software package.

A demo

The Excel Gear website now includes a demo to show the simplicity of the Excel-Lent Gear software. The demo takes a few minutes to download, and then runs through the numerical design of a spur gear needed to carry 350 hp at 1250 rpm and do so for 10,000 hr. The selections should be familiar to most mechanical engineers and include values such as the materials, mesh ratio, and safety factors. Results appear quickly in a green field at the screen bottom. A detailed sheet with many more of the gear characteristics also appears quickly after hitting the Calculate button. This information can be transferred to the included analysis program, with one button push, to calculate load and life values. Interpreting an analysis will take some experience.  Values found here include yield, bending, and contact stresses for the gear and pinion. Lastly, a Dimensions program provides the inspection data for the gears. Three input screens from the software appear here. The company is also announcing a cost of $995 for first time users.

Excel Gear Inc.

www.excelgear.com

Windpower Engineering & Development

RomaxWIND software is said to be the only package certified by GL Renewables Certification as a recognised method of calculating gear loads. The software developer says it provides a full manufacturing details which include gearbox design, manufacturing, testing support and technology training.

Drivetrain Analysis and Wind Turbine Lifecycle Engineering Company, Romax Technology has been awarded the GL Renewables (GL) A-Design Assessment for its new range of WT2000 licensed 2-MW gearboxes. This high level of certification means the gearbox design has passed the most stringent independent requirements set for the wind industry. The WT2000 2-MW gearbox is the fourth successful Romax gearbox and driveline which includes 1.5,  2.5, and 3 MW. The company continues to work with GL to ensure its latest designs meet with the standards set by GL guidelines for designs from 750 kW to 5 MW.

The 2 MW, WT2000 certification represents the culmination of successful collaboration between Romax, AMSC-Windtec, and a number of key gearbox manufacturers. The gearbox will be manufactured by Romax customers in China, Taiwan, India, and South Korea and has been designed for Windtec’s WT2000FC and WT2000DF wind turbines. The Romax engineering design team has achieved compliance with the guidelines set by GL, and has also delivered a gearbox design that meets the varying production criteria stipulated by each of the manufacturers within a competitive timeframe. This has resulted in a refined, fully certified gearbox design, available in multiple regions which in turn will strengthen and improve the offering of the local supply chain.

“The WT2000 design is based on our licensable 2MW wind turbine gearbox design,” says Andy Poon, Director of Renewables at Romax. “Working closely with AMSC-Windtec and GL Renewables Certification has proven our design to be straight forward to certify and easy to produce in volume by many manufacturers.

Romax Technology
romax.com

Windpower Engineering & Development