Cleaning system ensures smooth operation for wind power gears
With current global demand for energy exceeding the world’s crude production capacity, causing oil prices to soar, wind power is becoming an increasingly viable industry.
Over the past 15 years, the global wind power industry has been growing at an annual rate of more than 30percent. Consequently, green power (wind power, solar power, small-scale hydroelectric power, geothermal power, biomass fuel, and so forth) is rapidly becoming a smart investment.
Wind installations
According to the European Wind Energy Associationin 2003wind turbines worldwide attained a record capacity of 39294MWmeeting the needs of 47million people.
And the US counterpart of the European Wind Energy Associationthe American Wind Industry Associationestimates that wind installations worldwide will deliver more than 75000MW over the next decade and become a close to US$75billion industry.
The powerful global growth is expected to continue if policy incentives (fixed price and quantity systemsrenewable portfolio standard laws) remain and technological advances in wind-turbine manufacturing continue to extend product life and reduce operation and investment costs for electricity production.
Demand for green power is also on the increasesince coala principal energy sourcecontributes the largest amount of pollutants to the greenhouse effect.
Continuing growth
While most agree growth will continueit is also believed this will mainly take place in the top five wind-power producing countries – Germanywith a 36percent shareSpainat 16percentthe US at 16percentDenmark at sevenpercent and India with fivepercent.
When a new technology grows as fast as wind energy has done over the past few decadesconventional parts and solutions often no longer fit. Siemens Wind Power is one of the major wind turbine manufacturers that have helped develop wind-power technology.
Global capacity
With its headquarters in BrandeDenmarkthe company was founded as Bonus Energy A/S by Peter Sørensen in 1981. Sørensen was the sole owner until December 2004when he sold Bonus to Siemens.
As one of the top-five wind turbine makers in the worldSiemens has installed more than 5000 machines with a total capacity of more than 3300megawatt (MW) around the globe.
Its earliest turbines were 22–55kilowatt (kW)while today’s multi-megawatt giants are up to 3.6MW in size.
When Siemens developed its 1.3- MW model in 1999the company devised a new oil cooling and filter system for the turbine gearboxes.
Normal hydraulic hoses – typically 6-20mm in diameter – were too small or too stiff from steel reinforcements.
“We were looking for something bigger – 38mm (1.5inches) at first” says Tommy FriisSenior BuyerSiemens Wind Power.
“They had to be flexible – some of the hoses must be up to eight metres long. And we knew we’d need something that could go up to at least 63mm (2.5inches) or bigger. Today we’re at 102mm (4inches).”
Standards
The hoses would also have to be cleaned to very high standards (ISO18/16/13). Otherwiseparticles in the gear oil could cause a failure. Siemens had trouble finding a supplier that could meet its demands.
“At firsteverybody said our plan would not be possible” says Friis.
Trelleborg could not only meet Siemens’s strict demands for the partbut it made investments in a cleaning system to further seal the cooperation. “They’ve been willing to take action when it was needed” says Friis.
Cleaning system
Trelleborg’s cleaning system for its gear-oil hoses has resulted in continuing co-operation with Siemens Wind Power.
The key to Trelleborg’s continued success of its hose supply to Siemens Wind Power lies in a key investment for a cleaning system.
The hoseswhich range from 38–63mm in diameter and up to eight meters in lengthtransport oil from the gearbox to the filter/oil cooler and back.
“When Siemens was unsatisfied with the level of particles in the oil at firstTrelleborg invested in a completely new cleaning systemwhich flushes new hoses with oil at high pressure” says Frits JohansenDistrict ManagerTrelleborg Industrial Supply Products Denmark. “Since then” adds Johansen“no problems have occurred.”
Documentation
Johansen continues: “After each compression test and cleaningthe test results are transferred electronically to Siemens.
“This gives them documentation in the further process. The order number is also embossed on the casingso we have traceability. We can always tell when the hose was produced.”
Jack Jackson is with Trelleborg Industrial Supply Products Denmark. www.trelleborg.com/industrialhose
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