Workshop Recommendations

This leaflet contains general suggestions and calculation models. SSAB does hereby ex-pressly exclude any liability whatsoever for their suitability for individual applications. It is the responsibilty of the user of the manual to adapt the recommendations contained herein to the requirements of individual applications.

Project manager marketing Johan Lundin, Technical advisors Mikael Ringholm, Per Hansson

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WELDING RECOMMENDATIONSSSAB manufactures protection plate with lean chemical compositions which simplify welding. Armox plates should be welded with a consumable which produces a low hydrogen content in the weld metal. Good results require that hydrogen, which can induce cold cracking, is kept away from the weld area. Armox plates can be welded by any conventional welding method. All Armox grades can be welded to other weldable steel.

EDGE PREPARATIONA good fit between the work pieces is essential to minimize stresses and thereby the risk of cracking. All types of impuri-ties on and near the edges, such as mill scale, rust, oil, paint and moisture, should be removed before welding.

TACK WELDINGDuring tack welding the cooling rate is more rapid which increases the risk of cold cracking. In areas of high restraint the minimum length of each tack weld should be 50 mm to prevent hydrogen cracking.

PREHEAT TEMPERARATURES If austenitic consumables are used, the plate should be welded at least at room temperature (18–25°C). But when welding plates thicker than 30 mm, in combination with high levels of restraint, preheating is recommended.

If unalloyed or low-alloyed consumables are used preheating is necessary and dependent on plate thickness and restraint con-ditions.

1) Carbon equivalent (CEV)in accordance to IIW:

2) For plate thicknesses >80 mm, please contact SSAB

Steel grade Thickness range Carbon equivalent1

Armox 370T CL1 & CL2

3–150 mm 0.67–0.75 2

Armox 440T 4–30 mm 0.68–0.72

Armox 500T 3–115 mm 0.67–0.75 2

Armox 600T 4–20 mm 0.85 2

Armox Advance 5–7 mm 0.95

C + + + Mn6

Cu + Ni15

Cr + Mo + V5

Minimum recommended preheat and interpass temperatures for different plate thicknesses (mm)

Maximum recommended preheat/interpass temperatures

3 10 20 30 40 50 60 70 80 140 150

Armox 370 T Class 1Armox 370 T Class 2

Armox 440 T

Armox 500 T

Armox 600 T

Armox Advance

Armox 370 TArmox 370 T Class 2

Armox 440 T

Armox 500 T

Armox 600 T

Armox Advance

400°C

200°C

200°C

180°C

150°C

Thickness

3-80 mm3-150 mm

4-30 mm

3-140 mm

4-20 mm

5-7 mm

100°C

125°C

125°C

125°C

150°C

150°C

150°C

175°C

175°C

200°C

200°C

100°C + austenitic

100°C + austenitic

50°C75°C

100°C + austenitic

Measure the preheat temperature here

75 mm

Intended weld joint

Measure the temperature of the thickest plate in the joint. If the plate is 25 mm thick, measure the temperature 2 minutes after heating. If the plate is 12.5 mm thick, mea-sure the temperature after 1 minute, etc. The interpass temperature can be measu-red in the weld metal or in the immediately adjacent parent metal.

The temperature should be maintained throughout the entire weld operation, tack welding and root passes included.

Armox plates have been developed to have as low carbon equivalent as possible without loss in hardness, strength and ballistic properties. Typical carbon equivalents are shown in the table below.

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Manufacturer

Unalloyed or low-alloyed consumablesEN 499 xxx H5AWS: A 5.18-93 ER70S-6 E7018-1AWS: A 5.28-79 ER80S-G

Austenitic consumablesEN 1600 E 18 8 MnAWS A/SFA 5.4-92 E 307-15AWS A5.22 E 307 LT-2

ELEC

TRO

DES

ESAB OK 48.08, OK Femax 38.65OK 55.00

OK 67.45OK 67.52

FILARC Filarc 35Filarc 56 S Filarc BM 307

OERLIKON SpecialSupercord S

COMET 307SAFDRY R 307

THYSSEN Phoenix 120 KSH Grün K52W THERMANIT X

WIR

ES

ESAB OK Autrod 12.51OK Tubrod 15.00

OK Autrod 16.95OK Tubrod 14.36

FILARC Filarc PZ 6000Filarc PZ 6130

Filarc PZ 6070Filarc PZ 6470

OERLIKON FLUXOFIL 40Carbofil 100

NERTALIC 51SAFDUAL 651

THYSSEN TG 50 BUnion K52 THERMANIT X

The table on the previous page is applicable to single plate thickness when welding with a heat input of 1.7 kJ / mm. If the ambient humidity is high or the temperature is below +5 °C, the lowest recommended preheat temperatures given should be increased by 25 °C. This also applies to firmly clamped weld joints and if the heat input is 1.0-1.6 kJ / mm. Preheat tempera-tures for heat inputs lower than 1.0 kJ /mm can be determined by an applicable standard for high strength steels. One exam-ple is method B in European Norm EN 1011-2.

The lowest recommended preheat and interpass temperatures in the chart on the previous page are not affected at heat inputs higher than 1.7 kJ / mm.

CHOICE AND HANDLING OF CONSUMABLESConsumables should be selected on the basis of strength and toughness requirements in the joint. We recommendend soft consumables with a yield strength of up to 500 MPa.

In order to achieve an optimum combination of strength and toughness in the welded joint, select a consumable with as low strength as possible, but which still fulfils the strength require-ments for the joint. Using low-strength consumables can offer several benefits, such as higher toughness of the weld metal, higher resistance to hydrogen cracking and lower residual stresses in the joint. Designers should therefore attempt to

position the welds in low stress areas. Select the consumables which produce the lowest possible level of hydrogen in the weld metal for the given weld process.

The hydrogen content should be lower than or equal to 5 ml of hydrogen per 100 g of weld metal when welding with unal-loyed or low-alloyed welding consumables. Solid wires used in MAG and TIG welding can produce these low hydrogen contents in the weld metal. The hydrogen content for other types of welding consumables can best be obtained from the respective manufacturer.

If consumables are stored in accordance with the manufac-turer’s recommendations, the hydrogen content will be main-tained at the intended level. This applies, above all, to coated consumables and fluxes.

Welding can be carried out directly on the excellent primer,

due to its low zinc content. The primer can easily be brushed

or ground away in the area around the joint. Removing the

primer prior to welding can be beneficial, as it can minimize

the porosity in the weld and can facilitate welding in positions

other than the horizontal.

SSAB is a global leader in value added, high strength steel. SSAB offers products developed in close cooperation with its customers to create a stronger, lighter and more sustainable world.

SSAB has employees in over 45 countries and operates production facilities in Sweden and the US. SSAB is listed on the NASDAQ OMX Nordic Exchange, Stockholm. www.ssab.com.

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NS-V2-20

11. Halledo. Ö

sterbergs & Sörmlandstryck.