Nya Svetsaren 1, 1999. - Luleå University of Technology

ability by producing fewer irritatinginterruptions to equipmentwith built-in knowledge andequipment to improve health andsafety.More gas-related examples include:Gas supply systems. A centralgas supply system reduces theneed to move heavy cylinders.It also increases safety. In caseof fire, no or at least fewer cylindershave to be moved awayto safer areas.Shielding gases that improvethe working environment byreducing fume and gas emission.Gases that make it easier toset suitable process parametersand help to produce consistentbehaviour.Gas delivery security. Deliveryof a gas to a customer at shortnotice or within a specifiedtime limit. The distributionform, compressed gas in cylindersor liquids, is less importantfor the customer as longas the gas is there and has theright quality. The customerpays for a function rather thana component.Early warning signals of gasleakage. Leakage that couldlead to harmful situations.Information booklets that areinstructive, like the “Factsabout” information series.Global environmentThe impact on the global environmentof gases in welding andcutting is mainly a result of theproduction and transportation ofthe gases. A gas like argon, whichis used in shielding gases, comesfrom the air and returns to the airunchanged. The energy requiredto separate the small amountof argon that exists in the air(< 1%), however, has a negativeimpact on the environment, asdoes the energy needed to transportit. The amount of energy thatis needed to separate air is minimisedin the new and large airseparationplants. Fewer, largeplants, however, result in longertransportation. The transportationof liquid argon is comparativelylow in terms of energy consumptionwhen compared with thetransportation of heavy cylinderscontaining compressed gas. Effortsare therefore being made tominimise energy consumption inair-separation plants, to use liquidtransportation as far as possibleand to locate filling stations sothat the liquid argon can be putinto cylinders as close to the customeras possible. Carbon dioxideis extracted from waste products,mainly from fermentation processes.It is therefore used “a second”time before it is spread inthe air.Some examples of productsand applications which alreadymeet future requirementsMISON ® shielding gasesThere are now a variety ofMISON ® shielding gases for differentwelding processes, differentmaterials and different purposes.Gases that can improveproductivity, contribute to lowspatter formation, produce consistentpenetration, low surfaceslag formation and a good surfaceappearance, as well as improvingthe welders’ environment by reducingfume and ozone formation.RAPID PROCESSINGKnow-how packages that boostproductivity mainly by increasingthe deposition rate. No or onlysmall investments in equipmentare required. Today there arepackages for welding unalloyedand low-alloyed steels, for weldingcoated steels, for weldingstainless steels and for welding aluminium.New shielding gasmixturesNew shielding gas mixtures thatoptimise the MIG/MAG, TIG andlaser welding of “new” materials.Materials that are finding increasingindustrial use.Some examples of “new” materialsare duplex stainless steels,martensitic or super-martensiticsteels and aluminium alloys.AGA LASERLINEA complete range of gases andgas supply systems that producehigh performance in laser cuttingand in laser welding.ODOROX ®Oxygen with a small additive thatproduces an unpleasant smell.This gives an early warning ofoxygen leakage. Fires in an atmosphereof leaking oxygen arevery difficult to extinguish andcan lead to serious accidents. Earlywarning signals make it possibleto act before harmful situationsoccur.ConclusionThere will probably not be anydramatic changes in welding andcutting in the near future. When itcomes to industrial gases, the gasesand gas application know-howwill be important in welding andcutting beyond the year 2000.This will probably be even moreimportant than it is at present,due to other improvements inbase metals, filler materials, powersources, lasers and mechanisationequipment. In particular,application knowledge or aknowledge of how to use gases inthe optimum manner will behighlighted still further in thefuture.ODOROX ® and MISON ® areregistered trademarksAbout the authorKjell-Arne Persson is R&D Managerfor Manufacturing Industry.He graduated with an MSc in technicalphysics from the Royal Instituteof Technology in Stockholmand has been working at AGA since1980. He is involved in researchand development, first and foremostwithin the fields of weldingand cutting.76 Svetsaren No.1 1999