Automated system provides quality and productivity breakthrough in production of helicopter rotor blade heating systems.A precision tracked motion system from Gudel UK has beenspecified as a key element in a custom-engineered installation toautomate the production of de-icing systems on GKN Westland EH101helicopter rotor blades - thanks to its ability to position asuspended 250kg industrial robot with pinpoint accuracy andrepeatability over a 10 metre run. The resultant turn-keymanufacturing solution - designed, manufactured and projectmanaged by AEA Technology of Culham, Oxfordshire - has achieved abreakthrough in quality and productivity since supersedinglabour-intensive production methods at blades supplier, AerospaceComposite Technologies of Luton. Previously, de-icing systemswere applied manually by spraying strips of metal onto the 7.5mlong glass reinforced plastic blades.
Today, the Gdel equipmentat the heart of the new installation is used in conjunction witha Staubli Unimation RX130 robot to streamline the whole processfrom surface preparation, marking out and spraying, through tofinal component trimming.
The elimination of human variables hasnot only enabled the new system to improve coating thicknessconsistency - with a marked reduction in re-work time and costs -but also to achieve a significant increase in productionthroughput.
In operation, the installation's robot initiallyblasts the moulded blade with silicon carbide grit to bothprepare and key its surface.
After a tool change, the robotundertakes the metal spraying operation over designated areas ofthe blade.
Finally, it selects a polycrystalline diamond (PCD)tipped router to trim the edge to a dimensional tolerance of+0.25 mm.
According to AEA Technology's Peter Jackson,'Each blade incorporates a complex 'burp' profiledesign.
These too, must be held to close tolerances.Additionally, high manufacturing repeatability and consistency inthe de-icers' sprayed metal surface must be maintained inorder to minimise the risks of localised variations which couldcause significant hot or cold spots over the blade'ssurface.' 'When working such large components to thisprecision, we even had to take process temperature variationsinto consideration in the installation's design,' hecontinues.
'By locating the robot's microswitch datumat the centre of the track motion system's 10 metre run, wehave effectively eliminated thermal drift - enabling overallrepeatability of better than 0.03 mm at any point along theblade's surface.' Another major concern in theselection of the positioning system was the operating environmentassociated with the grit blasting operation.
However, afterviewing an equivalent Gdel installation at CosworthEngineering's foundry in Worcester, AEA Technology wasconfident of its ability to cope with the stringent operatingrequirements of the de-icer application.
This performance wassubsequently confirmed through pilot trials of the robot andtrack system combination prior to final system integration.
Thefact that all the track motion modules come from Gudel'sstandard range has proved to be a further bonus, helping AEATechnology to ensure that the new manufacturing system has beencompleted, installed and commissioned at the customer's siteon time, as well as on budget.
'The Gudel system is acentral element of the installation.
Its capabilities have beenbacked by high in-service reliability, both on this and othersimilar installations we have undertaken during the past twoyears,' Mr Jackson confirms.
The TM series track motionmodules selected for this demanding application represent justone of a range of precision linear and drive technology solutionsoffered by Gudel.
Designed for use with industrial robots fromall leading manufacturers, TM series modules are geared to therequirements of machine tool, automation and special machinebuilding applications.
The company's complementarymulti-axis gantry loading equipment, automation machinery andpress transfer units are ideal for installations requiring highspeed, high acceleration or precise positioning of componentsweighing up to several tonnes.
They are widely employed for highvolume metal working, assembly or manufacturing applications - inparticular within the automotive, aerospace, defence, electronicsand process sectors.
A complete spectrum of modular components,ranging from precision drive pinions, racks, rollers, tocarriages and guideways is also available and can be supplied ina variety of materials and surface finishes to combat corrosive,aggressive or hazardous operating environments.