Product Description

Characteristics  : Grade **4L is a Molybdenum and Copper alloyed Cr-Ni austenitic stainless steel with low Carbon content. Its specific characteristics are: • Austenitic micro structure • High resistance to: - pitting and crevice corrosion - stress corrosion and corrosion fatigue - uniform corrosion • Good ductility and weldability Dimensions Tubular products in grade **4L are not stock standard, but can be manufactured in most common standard sizes within Stainless Tubular Products product range. Tubes & Pipes • OD: *7.*****9.0 mm • WT: 1.***5.4 mm • Lengths: up to *2 m Heat exchanger tubes • OD: *2.****4.3 mm • WT: 0.**4.0 mm • Lengths: up to *5 m Executions Tubes, Pipes and Butt Weld Fittings • Welded with- or without filler metal • Unannealed, pickled • Solution annealed and pickled • With- or without BCW (Bead Cold Worked) • Bevelled ends according to standards Information given in this data sheet may be subject to alterations without notice. Care has been taken to ensure that the contents of this publication are accurate but Outokumpu and its affiliated companies do not accept responsibility for errors or for information that is found to be misleading. Suggestions for or descriptions of the end use or application of products or methods of working are for information only and Outokumpu and its affiliated companies accept no liability in respect thereof. Before using products supplied or manufactured by the company the customer should satisfy himself of their suitability. Technical and other data in this publication are typical and may not be regarded as guaranteed maximum or minimum values unless this is specifically stated. Heat exchanger tubes • No BCW for laser welded tubes, h max = 0.*5 mm • Tig welded tubes are BCW • Solution annealed and pickled Corrosion resistance Grade **4L has a high corrosion resistance to a wide range of corrosive environments. A PRE of *5 indicates that the steel grade has good resistance to warm sea water and other high chloride environments. High nickel content results in a much better resistance to stress corrosion cracking than the standard austenitic grades. Copper adds resistance to sulphuric and other reducing acids, particularly in the very aggressive mid concentration range. In most environments **4L has a corrosion performance intermediate between the standard austenitic grade **6L and the very highly alloyed 6 Mo and similar super austenitic grades. See Outokumpu Corrosion Handbook for more information. Product standards Europe • EN ******2 Welded SS tubes for general purposes. • EN ******7 Welded SS tubes for pressure purposes. • EN ******3: Butt-welding pipe fittings. Wrought austenitic and austenitic-ferritic (Duplex) stainless steels without specific inspection requirements. • EN ******4: Butt-welding pipe fittings. Wrought austenitic and austenitic-ferritic (Duplex) stainless steels with specific inspection requirements. USA • ASTM A **9 Welded Austenitic SS Heat Exchanger Tubes • ASTM A **9 Welded and seamless Austenitic SS Tubing • ASTM A **2 Welded and seamless Austenitic SS Pipes • ASTM A **8 EF Welded Austenitic Pipe with filler metal • ASTM B **3 Welded Pipe • ASTM B **4 Welded Tube Pressure vessel approvals Europe The Pressure Equipment Directive PED regulates the use of welded SS pipe in most European countries. Outokumpu Stainless Tubular Products fulfils the Directive, and is an approved manufacturer of welded SS tubes. Outside Europe Pressure vessel regulations are authorized to ASME. ASME Section VIII, Division 1, Table UHA**3, shows design values for tube and pipe manufactured and tested according to ASME SA***9 and SA***2 respectively. ASME B*1.1 Power Piping and ASME B*1.3 Process Piping prescribes design and design stress values for approved pipe materials. Fabrication Welding Common welding methods for tubular products are: • MMA, SMAW (Shielded Metal Arc Welding) • TIG, GTAW (Gas Tungsten Arc Welding) • MIG, MAG, GMAW (Gas Metal Arc Welding) • FCAW (Flux-Cored Arc Welding) • PAW (Plasma Arc Welding) • SAW (Submerged Arc Welding) The general recommendation for shield and plasma gas is pure Argon (TIG/PAW). Additions of **3 % hydrogen H2 and **3 % nitrogen N2 will improve the penetration and corrosion resistance. As backing/ purging gas the general recommendation is pure Argon or Formier gas (*0 % N2 and *0 % H2). General filler recommendation for steel grade **4L can be found in the table below. Welding without filler metal not followed by post heat treatment will reduce the corrosion resistance and is therefore not recommended. See Outokumpu Welding Handbook for more information. Cold forming Excellent cold forming properties. The same properties as for other standard austenitic stainless steels. Hot forming Grade **4L is slightly harder at higher temperatures than austenitic standard grades. Forming at temperatures in the range ********0°C does not require any post heat treatment, if the operation is followed by a reasonable fast cooling, (>**0°C/min). Heat treatment The normal annealing temperature is ********0°C followed by rapid cooling to at least **0°C. At temperatures between ******0°C, inter metallic phases that impair the properties will form within a few minutes. Applications • Process equipment in chemical industry • Bleaching equipment in the pulp and paper industry • Flue-gas cleaning • Desalination • Seawater handling • Heat exchangersCharacteristics Grade **4L is a Molybdenum and Copper alloyed Cr-Ni austenitic stainless steel with low Carbon content. Its specific characteristics are: • Austenitic micro structure • High resistance to: - pitting and crevice corrosion - stress corrosion and corrosion fatigue - uniform corrosion • Good ductility and weldability Dimensions Tubular products in grade **4L are not stock standard, but can be manufactured in most common standard sizes within Outokumpu Stainless Tubular Products product range. Tubes & Pipes • OD: *7.*****9.0 mm • WT: 1.***5.4 mm • Lengths: up to *2 m Heat exchanger tubes • OD: *2.****4.3 mm • WT: 0.**4.0 mm • Lengths: up to *5 m Executions Tubes, Pipes and Butt Weld Fittings • Welded with- or without filler metal • Unannealed, pickled • Solution annealed and pickled • With- or without BCW (Bead Cold Worked) • Bevelled ends according to standards Information given in this data sheet may be subject to alterations without notice. Care has been taken to ensure that the contents of this publication are accurate but Outokumpu and its affiliated companies do not accept responsibility for errors or for information that is found to be misleading.

Heat exchanger tubes • No BCW for laser welded tubes, h max = 0.*5 mm • Tig welded tubes are BCW • Solution annealed and pickled Corrosion resistance Grade **4L has a high corrosion resistance to a wide range of corrosive environments. A PRE of *5 indicates that the steel grade has good resistance to warm sea water and other high chloride environments. High nickel content results in a much better resistance to stress corrosion cracking than the standard austenitic grades. Copper adds resistance to sulphuric and other reducing acids, particularly in the very aggressive mid concentration range. In most environments **4L has a corrosion performance intermediate between the standard austenitic grade **6L and the very highly alloyed 6 Mo and similar super austenitic grades.

Product standards Europe • EN ******2 Welded SS tubes for general purposes. • EN ******7 Welded SS tubes for pressure purposes. • EN ******3: Butt-welding pipe fittings. Wrought austenitic and austenitic-ferritic (Duplex) stainless steels without specific inspection requirements. • EN ******4: Butt-welding pipe fittings. Wrought austenitic and austenitic-ferritic (Duplex) stainless steels with specific inspection requirements. USA • ASTM A **9 Welded Austenitic SS Heat Exchanger Tubes • ASTM A **9 Welded and seamless Austenitic SS Tubing • ASTM A **2 Welded and seamless Austenitic SS Pipes • ASTM A **8 EF Welded Austenitic Pipe with filler metal • ASTM B **3 Welded Pipe • ASTM B **4 Welded Tube Pressure vessel approvals Europe The Pressure Equipment Directive PED regulates the use of welded SS pipe in most European countries. Outokumpu Stainless Tubular Products fulfils the Directive, and is an approved manufacturer of welded SS tubes. Outside Europe Pressure vessel regulations are authorized to ASME. ASME Section VIII, Division 1, Table UHA**3, shows design values for tube and pipe manufactured and tested according to ASME SA***9 and SA***2 respectively. ASME B*1.1 Power Piping and ASME B*1.3 Process Piping prescribes design and design stress values for approved pipe materials. Fabrication Welding Common welding methods for tubular products are: • MMA, SMAW (Shielded Metal Arc Welding) • TIG, GTAW (Gas Tungsten Arc Welding) • MIG, MAG, GMAW (Gas Metal Arc Welding) • FCAW (Flux-Cored Arc Welding) • PAW (Plasma Arc Welding) • SAW (Submerged Arc Welding) The general recommendation for shield and plasma gas is pure Argon (TIG/PAW). Additions of **3 % hydrogen H2 and **3 % nitrogen N2 will improve the penetration and corrosion resistance. As backing/ purging gas the general recommendation is pure Argon or Formier gas (*0 % N2 and *0 % H2). General filler recommendation for steel grade **4L can be found in the table below. Welding without filler metal not followed by post heat treatment will reduce the corrosion resistance and is therefore not recommended.

Cold forming Excellent cold forming properties. The same properties as for other standard austenitic stainless steels. Hot forming Grade **4L is slightly harder at higher temperatures than austenitic standard grades. Forming at temperatures in the range ********0°C does not require any post heat treatment, if the operation is followed by a reasonable fast cooling, (>**0°C/min). Heat treatment The normal annealing temperature is ********0°C followed by rapid cooling to at least **0°C. At temperatures between ******0°C, inter metallic phases that impair the properties will form within a few minutes.

Applications • Process equipment in chemical industry • Bleaching equipment in the pulp and paper industry • Flue-gas cleaning • Desalination • Seawater handling • Heat exchangers