“Hitsauksen kehityksestä kaasumiehen silmin”

Pauli Toiviainen, AGA Pohjois-Euroopan Regioona

Already the old Egyptians…

Welding by combination of heat and pressure has been used from at least 5000 b.C. This was the only method until the 1880’s

Milestones in welding from 1880

1880 1890 1900 1910 1920 1930 1940 1950 1960 1970

Metal arcCovered electrodes

TIG MIG

Electron beam

Carbon arc

Oxy AcetyleneSubmerged arc

MAG (CO2)

Laser welding

Plasma welding

1940’s : Innovation of TIG and MIG/MAG in the US1960’s : The methods are spread commercially1970’s : MAG welding becomes the dominating method in W. Europe (instead of

MMA)1978 : MISON shielding gases for better working environment1980’s : Robot welding

Development 1940’s-1980’s

Note the drum pack for filler wire (AGA 1960’s)

Development 1990’s

• High deposition rate MAG welding– RAPID PROCESSINGTM (AGA)

– T.I.M.E. Process (Fronius)

– Twin Arc/Tandem welding

• MIG brazing

RAPID PROCESSING

ConventionalMAG

RAPID ConventionalPROCESSING MAG

Plate thickness [mm] 3 3Welding speed [cm/min] 120 60Deposition rate [kg/h] 5 2,5

Conventional MAG, v = 160 cm/min

RAPID ARC®, v = 160 cm/min

RAPID ARC®

• High productivity MAG welding process• Standard equipment is used• Mechanized welding• Shielding gas with low CO2-content

Shielding gas development (steel welding):• Lower CO2-content (8-10% in Argon)

Tandem-MAG

• Higher deposition rate• Higher welding speed• Accessibility may be limited (bigger welding head) • More programming due to two arcs• Difficult to minimize spatter• More sensitive process• Harder for operator to fine tune

Shielding gas development (steel welding):• Lower CO2-content (8-12% in Argon)• Helium addition

Development during 2000’s

• New variants due to better and faster electronics– CMT (Fronius)

– Cold Arc (EWM)

– AC-MIG/MAG (OTC)

– Etc..

• Hybrid welding– Laser-MAG

– Plasma-MAG

”Cold” processes

“Cold” processes - benefits

Welding of thin material:– Less distortion

– Almost no spatter

– Possible to substitute TIG-welding

– Better gap bridging

– Suitable for MIG-brazing

Shielding gas development (according to Fronius):• No influence of shielding gas– Pure CO2 (steel welding)

– Pure Argon (brazing and Ni-base welding)

Stainless steel, 0,5 mmOverlapFiller metal 0,8 mmWelding speed: 2,0 m/min

Manual MIG-brazingFiller metal: 1,0 mm CuSi3Gap: 4 mm

No influence of shielding gas with CMT?

Argon Ar+0,05%CO2+30%He+2%H2

CM

TC

MT pulsed

Base material: carbon steel, Filler: alloy 625, cladding

Hybrid welding with laser-MIG/MAG

• Lower laser energy compared to laser welding– Arc energy is added

– Arc decrease reflection of laser beam

• Higher welding speed• Lower heat input• Better tolerance to gap variations

Shielding gas development (steel welding):• “Normal” mixtures works fine• Optimization still ongoing

MAG

Laser-MAG

Laser

Trends for shielding gases - MIG/MAG & TIG

Driven by development of power sources• MAG-welding of carbon steel with pure CO2 or 82/18-mixture– Fast, reliable electronic control of power sources

Driven by development of construction material• Nitrogen addition (TIG)– Duplex and Superduplex

– Lean duplex

• Micro additions of CO2 and O2 in Argon (MAG)– Ni-base alloys

– Other high alloyed materials

• Helium addition (TIG and MIG/MAG)– All high alloyed materials

Shielding gas components, TIG

Ar

Base gasWork environment•Ozone reducing•(Arc stability)

Productivity•Fluidity•Wetting•Penetration

Standard Added value

Metallurgy•Corrosion•Strength

Productivity•Fluidity•Wetting•Penetration•Reducing

Ar + NOAr + NO + HeAr + NO + He + H2Ar + NO + He + H2 + N2

Shielding gas components, MAG

Ar + CO2 + O2

Base gasArc stability

Work environment•Ozone reducing

Productivity•Fluidity•Wetting•Penetration

Standard Added value

Ar + CO2 + O2 + NOAr + CO2 + O2 + NO + HeAr + CO2 + O2 + NO + He

Trends for shielding gases - Laser

Driven by development of lasers• CO2 Laser-welding of carbon steel– Helium replaced by:

– Argon/CO2-mixtures

– Argon/Helium-mixtures

• Diode laser welding of carbon steel– Argon/CO2-mixtures

Weld Metal consumption 1974-2006

0

2000

4000

6000

8000

10000

12000

14000

1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006EYear

Tons

MMA MIG/MAG FCAW SAW

Gross weight 14,400 ktons Gross weight 12,610 ktons

•Source: ESAB

Shieding Gases volume development, North Europe

REN

0 M3

1 000 000 M3

2 000 000 M3

3 000 000 M3

4 000 000 M3

5 000 000 M3

6 000 000 M3

7 000 000 M3

2004 2005 2006 2007 2008 2009 2010 2011 2012

GARCORGONMISON PUREMISON 8MISON 18MISON 25Result

Gustav Dalen 1904

”Auta asiakasta parantamaantoimintansa kannattavuutta, laatua ja turvallisuutta”