Sandvik 3R60™: Premium Austenitic Chromium‑Nickel Steel for Corrosion‑Resistant Applications

Sandvik 3R60™ is used for a wide range of industrial applications where steels of type ASTM 304 and 304L have insufficient corrosion resistance. Typical examples are: heat exchangers, condensers, pipelines, cooling and heating coils in the chemical, petrochemical, pulp and paper and food industries.

Annealing after cold bending is not normally necessary, but this point must be decided with regard to the degree of bending and the operating conditions. Heat treatment, if any, should take the form of stress relieving or solution annealing, see under Heat treatment.

General corrosion: Sandvik 3R60 has good resistance in

Stress corrosion cracking: Austenitic steels are susceptible to stress corrosion cracking. This may occur at temperatures above about 60°C (140°F) if the steel is subjected to tensile stresses and at the same time comes into contact with certain solutions, particularly those containing chlorides. Such service conditions should therefore be avoided. Conditions when plants are shut down must also be considered, as the condensates which are then formed can develop conditions that lead to both stress corrosion cracking and pitting.

In applications demanding high resistance to stress corrosion cracking, austenitic-ferritic steels, such as Sandvik SAF 2304 or SAF 2205 are recommended. See data sheets S-1871-ENG and S-1874-ENG.

Intergranular corrosion: Sandvik 3R60 has a low carbon content and therefore better resistance to intergranular corrosion than steels of type AISI 316.

The TTC-diagram, attached on the right side of the datasheet, which shows shows the result of corrosion testing for 24 hours in boiling Strauss solution (12% sulfuric acid, 6% copper sulphate). The resistance to grain boundary attack is much better for AISI 316L than for AISI 316. This is an advantage in complicated welding operations.

Pitting and crevice corrosion: Resistance to these types of corrosion improves with increasing molybdenum content. Sandvik 3R60, containing about 2.6% Mo, has substantially higher resistance to attack than these steels of type AISI 304 and also better resistance than ordinary AISI 316/316L steels with 2.1% Mo.

Gas corrosion Sandvik 3R60 can be used in:

Creep behavior should also be taken into account when using the steel in the creep range.

In flue gases containing sulfur, the corrosion resistance is reduced. In such environments the steel can be used at temperatures up to 600-750°C (1100-1380°F) depending on service conditions. Factors to consider are whether the atmosphere is oxidizing or reducing, i.e. the oxygen content, and whether impurities such as sodium and vanadium are present.

Tubes are delivered in heat treated condition. If additional heat treatment is needed after further processing the following is recommended.

Stress relieving: 850-950°C (1560-1740°F), cooling in air.

Solution annealing: 1000-1100°C (1830-2010°F), rapid cooling in air or water.

Hot bending is carried out at 1100-850°C (2010-1560°F) and should be followed by solution annealing.

Forms of supply:

Seamless tube and pipe in Sandvik 3R60 is supplied in dimensions up to 260 mm outside diameter in the solution annealed and white-pickled condition or solution annealed in a bright-annealing process.

We can also deliver other product forms from stock in a grade corresponding to ASTM 316L mainly:

Sizes in stock

Seamless tube is stocked in a wide range of sizes according to ISO. Heat exchanger and instrumentation tubes are also stocked in BWG-and SWG-sizes. Hollow bar is stocked in a large number of sizes as SANMAC 316L (see data sheet S-1840-ENG). Details of our manufacturing programme are given in catalogue S-110-ENG.

The weldability of Sandvik 3R60 is good. Welding must be carried out without preheating and subsequent heat treatment is normally not required. Suitable methods of fusion welding are manual metal-arc welding (MMA/SMAW) and gas-shielded arc welding, with the TIG/GTAW method as first choice.

For Sandvik 3R60 , heat input of <2.0 kJ/mm and interpass temperature of <150°C (300°F) are recommended.

Recommended filler metals:

• TIG/GTAW or MIG/GMAW welding
  • ISO 14343 S 19 12 3 L / AWS A5.9 ER316L (e.g. Exaton 19.12.3.L)
• MMA/SMAW welding
  • ISO 3581 E 19 12 3 L R / AWS A5.4 E316L-17(e.g. Exaton 19.12.3.LR)
  • ISO 14343 S 19 12 3 L / AWS A5.9 ER316L (e.g. Exaton 19.12.3.L) wire or strip electrodes are recommended for overlay welding of tube sheets and high-pressure vessels in cases where corrosion resistance, equal to that of Sandvik 3R60, is required.