Special Alloys

 

UNS S20910 - XM19

Duplex

UNS S31803

Super Duplex

UNS S32550

UNS S32750

UNS S32760

 

 

 

 

 

 

 

 

 

 

 

 

 

 

UNS S31803 (SAF 2205® TYPE)

A widely used duplex steel with a PREN about 34. Duplex steels combine high strenght and corrosion resistance. With a near equal mix of austenite and ferrite, they give yeld strenghts 30% higher and tensile strenghts marginally higher than comparable nitrogen-containing austenitics. Their resistance to stress-corrosion cracking in neutral chlorides is superior to that of the 18/10 and 18/12/3 austenites. In high chloride acidic or moderately sour environments where hydrogen or sulphide stress cracking is more likely, higher alloyed austenitcs need also to be considered.

Impact values are high and transition temperatures of base materials vary around -50°C. However, the proportion and orientation of ferrite in welds and base materials may significantly affect toughness at subzero temperatures.

Exposure to moderate and high temperatures and less rapid cooling may cause embrittlement. Accordingly, design stress values in ASME II and BS 5500-1991 do not extend above 300-315°C for S31803/S39205/X2 CrNiMoN 22 5 3.

Chemical composition (nominal) %

 

C
max		 Si
max		 Mn
max		 P
max		 S
max		 Cr Ni Mo N
0.030 1.0 2.0 0.030 0.015 22 5 3.2 0.18

Properties


The following values apply to material in the solution annealed condition. Tube and pipe with wall thicknesses above 20 mm (0.787 inch) may have slightly lower values. For seamless tubes with a wall thickness <4 mm we can guarantee proof strength (Rp0.2) values that are 10% higher than those listed below at 20°C (68°F) as well as those listed at higher temperatures. More detailed information can be supplied on request.
 

Metric units

Proof strength
Rp0.2
MPa min.		 Rp1.0
MPa min.		 Tensile strength
Rm
MPa		 Elong.
A %
min.		 Elong.
A2 %
min.		 Hardness
HRC
max.
450 500 680-880 25 25 28

Seamless tube and pipe in the cold-worked condition
Intended for oil and gas production

Proof strength
Rp0.2
MPa min		 ksi
min		 Tensile strength
Rm
MPa min		 ksi
min		 Elong.
A2 %
min
895 130 965 140 10

TUBES AND PIPES  -  ASTM A790 / A312 / A530

Longitudinally welded according to ASTM A789 and A790 - Heat treated at 1080°C - 100% eddy current tested

BUTTWELD FITTINGS

90° and 45° long and short radius elbows - Tees and reducing tees - Concentric and excentric reducers - Caps and Stub ends

SHEETS AND PLATES

From coil and from slabs - Plasma cut and special shapes

ROUND BARS

Our Partners

Ilta Chibro - Lorowerk - Novopress

Eucaro - Geberit - Georg Fischer

Our Agent in Croatia