Alloy 28 possesses good weldability. Suitable welding methods are manual metal-arc with covered electrodes and gas shielded arc welding, such as TIG and MIG. The heat input should be 1 kJ/mm maximum and the interpass temperature 150°C (300°F) maximum. A stringer bead welding technique should be used. Welding should be undertaken without preheating and, if correctly performed, there will be no need for any subsequent heat treatment. To maintain full corrosion resistance of the weld joint, welding must be followed by thorough cleaning to ensure removal of all oxides and slag particles.
In common with all austenitic stainless steels, Alloy 28 has low thermal conductivity and high thermal expansion. Welding should, therefore, be carefully planned in advance so that distortion of the welded joint can be minimized.
The welding of fully austenitic steels usually involves the risk of hot cracking in the weld metal, particularly if the weldment is under constraint. However, since Alloy 28 is an alloy with a very low impurity content, it is not particularly prone to this type of cracking.
As a filler metal for gas shielded arc welding, 27.31.4.LCu wire is recommended. For manual metal-arc welding, covered electrodes of the 27.31.4.LCuR type are recommended.
When Alloy 28 is welded to carbon steel, it is also possible to use nickel base filler metals, such as Alloy 60.
Datasheet
updated 2015-02-16 10:39:36 (supersedes all previous editions)
Alloy 28 is a high-alloy multi-purpose austenitic stainless steel for service in
highly corrosive conditions. The grade is characterized by:
Standard
Seamless tube and pipe: | ASTM B 668; EN 10216-5; SEW 400 (Feb 1991); SS 14 25 84; NFA 49-217 |
Plate, sheet and strip: | ASTM B 709, EN 10088-2; SS 14 25 84 |
Bar steel: | EN 10088-3; SS 14 25 84 |
Fittings: | ASTM A 403 (chemical composition and mechanical properties according to ASTM B668) |
Approved by the American Society of Mechanical Engineers (ASME) for use in accordance with ASME Boiler and Pressure Vessel Code, section III, section I (Code Case 1325-18) and section VIII, division 1. VdTÃœV-Werkstoffblatt 483 (Austenitischer Walz- und Schmiedestahl) NACE MR 0103 (Materials Resistant to Sulfide Stress Cracking in Corrosive Petroleum Refining Environments) NACE MR0175/ISO 15156 (sulphide stress cracking resistant material for oil field equipment) NGS 1608 (Nordic rules for application) valid for Alloy 28 made by
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North America |
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Asia |
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Mid East/Africa |
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Western Europe |
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Australasia |
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Eastern Europe |
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UAE |
• | Sri Lanka | • | Bahrain |
• | Russia | • | Egypt |
• | Portugal | • | Turkey |
• | Spain | • | Singapore |
• | Brazil | • | Thailand |
• | Chile | • | Malaysia |
• | Venezuela | • | Indonesia |
• | Costa Rica | • | Poland |
• | USA, U.A.E | • | Italy |
• | Oman | • | Canada |
• | Saudi Arabia | • | Angola |
• | Qatar |