Nya Svetsaren 1, 1999. - Luleå University of Technology

comparable table arrangementfor a dry process. What is more,handling cutting with water tablestakes time and introduces otherdisadvantages like those touchedupon earlier.However, the dry processesalso have inherent disadvantageswhen it comes to the environmentalissues of noise and, particularlyin the case of laser, radiation.As has already been said,the use of laser cutting will increaseas a result of reduceddross appearance, greater accuracyand the higher productivitythat can be obtained with dry cuttingtables.The author believes that thiswill take place, although the actualcutting speed for laser versusplasma-water at the present time,for 20 mm MS, for example, is 1m/min compared with 3 m/min.For shipyards in particular,when they invest in new cuttingfacilities, it will be attractive tochange to laser and it will alsothen be possible to handle the environmentalissues in the idealmanner. In short, this will resultin the complete removal of theoperator and other manual activitiesfrom the installation site anda change to complete reliance onremote control, remote handlingand remote surveillance. For thesupplier and designer of thesecutting installations, there is stillsome way to go before all the facilitiesfor the programming andsurveillance of the relevant cuttingparameters are available, butit is thought that this will be thetrend in development as far as laseris concerned. While this is beingimplemented, we shall probablysee the development of thelaser technique towards copingwith thicker material while maintainingthe level of precision. Thecurrent standard is 25–30 mm forMS. The double-focus techniqueis one way of achieving this.Finally, it is worth noting thatlaser cutting lends itself to interestingprecision jobs such as contourcutting, with or without bevel,in one operation on twodimensionalor three-dimensionalworkpieces, also including thecutting of small holes, with orwithout chamfers. Figures 6 and 7Fig. 6. An S-axis laser-cutting head which is fully programmable.Fig. 7. A modern laser-cutting installation for large plate formats with screeningfrom radiation.illustrate this development in lasercutting.At present, fine-beam plasmacutting has potential for thin platecutting which can be furtherexploited when the appropriatesolutions for reducing or avoidingthe inherent noise level are introduced.Fine-beam plasma cutting isvery attractive investment-wise,as compared with laser cutting,for a number of applications wherethe highest precision is notnecessary (compare with Fig. 2).At the same time, it is to be expectedthat, within the foreseeablefuture, fine-beam plasma willincrease in capability from thepresent maximum 20 mm thicknessup to a maximum of 50 mm,both figures referring to MS.SummaryOver the years, environmental issueshave become an increasinglyimportant point on the agendawhen it comes to the design ofcutting systems. The current technology,its productivity merits anddeficiencies are briefly described,as they relate to present and upcomingenvironmental issues inthe fields of dust, fume and gases,noise, radiation and ergonomicsin general. With that as the startingpoint, a discussion of the outlookfor improvements–the waysand means of establishing improvedenvironmental conditions,while paying due consideration toproductivity, as seen through theeyes of a manufacturer of cuttingsystems, featuring a horizonstretching into the next millennium–ispresented.About the author:Klaus Decker, Dipl.-Ing. isManaging Director of ESABCUTTING SYSTEMS.Svetsaren No.1–2 1999 37