Guide forwelding ferriticaustenitic duplex stainless. The pipe shall be made using electric resistance welding erw or an automatic fusion welding process with no addition of filler metal during the. Jun 28, 2017 weldability and jointability of duplex stainless steels. Jatandeep singh1 nishant goswami2 1,2 department of manufacturing processes and automation engineering 1,2 netaji subhas institute of technology, dwarka, new delhi, india abstract duplex stainless steels are unrivalled in a large number. Physical and chemical phenomena influencing slag detachability during. General understanding in welding dissimilar metals all stainless steel deposits on carbon or lowalloyed steel should be made with filler metal of sufficiently high alloy content to ensure that normal amounts of dilution by carbon steel will not result in brittle weld. The stainless steels offer a remarkable range of strengths. In standard laser welding, using argon as the shield gas, nitrogen can be lost from the weld pool and the austenite content of the weld will be reduced. Weld failure analysis of 2205 duplex stainless steel nozzle. Duplex stainless steels have a twophase structure of almost equal proportions of austenite and ferrite.
Welding highlights welding guide for sandvik duplex stainless. Even in the fully soft condition they have tensile strengths somewhat greater than that of mild steel. Rapid cooling should be avoided, as the material structure may suffer. Ferrite control in duplex stainless steel weld metal although it has little influence on yield and tensile strength, controlling the efn of the weld deposit has a marked effect on ductility by d. There is often the need to weld duplex superduplex steel to lower alloyed ferritic steel, a 300 series stainless steel or a dissimilar grade of duplex steel. Welding super duplex stainless steel introduction commercial super duplex stainless steel grades have been introduced in industry for a variety of high technological applications.
In comparison with the grades with 22%cr, super duplex stainless steel grades are characterized by an increased cr 25% and mo 24% content, a high nlevel. The composition of the most common duplex steels lies within the range 2226% cr, 47% ni, and 03% mo, normally with a small amount of nitrogen 0. Improper welding techniques and procedures can introduce 1960s. The influence of nitrogen from welding on stainless steel. Ss201 is a lowercost alternative to the conventional crni austenitic stainless steels, such as ss304. At the time of the solidstate cooling to ambient temperature, the.
Welding parameters for duplex stainless steels imoa. Duplex stainless steel welding free download as powerpoint presentation. Part 1 presented by catherine houska march, 2014 the history, performance, sustainability and applications for stainless steel as a structural material will be introduced, with references to specific projects. The 300 series stainless steels are generally welded to duplex steels with a 309mol 23crni2. Duplex stainless steel, welding, field experience, weld metal properties, quality system 1.
In this work, the failure mechanism of a reactor vessel after 1 year of operation was studied. Duplex stainless steels a simplified guide welding. Metallurgy those of the more familiar austenitic stainless steels. Virtually all welding processes used on austenitic stainless steels are applicable to duplex stainless steels. By using the guidelines in en iso 38342, welding procedure specifications, system for nondestructive testing and post weld handling can be controlled. Duplex stainless steel limitations plate cost duplex stainless steel welding welding is seen as a disadvantage but is probably no more difficult to weld than the austenitics make sure material starts out in the right condition through composition and heat treatment use astm a923 standard and astm a1084 lean for. Duplex stainless steels welding guidelines industeel arcelormittal.
Duplex and super duplex stainless steels are commonly used for offshore applications and have their own unique fabrication and welding methods that are fully understood and practised by langfields. Welding duplex and superduplex stainless steel industry guide. At constant current, an increase in the potential by 10 volts v can increase the weld metal nitrogen content by 0. For example, the importance of having sufficient nitrogen in the duplex stainless steel base metal has been repeatedly emphasised. Duplex stainless steel limitations plate cost duplex stainless steel welding welding is seen as a disadvantage but is probably no more difficult to weld than the austenitics make sure material starts out in the right condition through composition and heat treatment. Laser welding of duplex stainless steel with nitrogen as. Adopting the welding consumables to this base material will automatically make the weld metal suitable for the total range of super duplex stainless steels.
This book is concerned with laser beam welding and its effect on size and microstructure of fusion zone then, on mechanical and corrosion properties of welded joints of the widely used 2205 duplex stainless steel plates. Since welding is widely used in the fabrication of pressure vessels, understanding the causes that result in the cracking is critical to the application of the duplex stainless steel vessels. In this study aisi 316 types of austenitic stainless steels were welded by fcaw flux cored arc welding using er 316l flux cored filler metal under various shielding gas compositions such as ar. How to weld type 2205 code plus two duplex stainless steel. There is often the need to weld duplexsuperduplex steel to lower alloyed ferritic steel, a 300 series stainless steel or a dissimilar grade of duplex steel. Cast steel buckets, cheek plates, asphalt equipment 2 1 galvanized steel duct work, angle iron, channels 1 dissimilar steels carbonalloy steels to stainless steel 1 2 3 3 manganese steel hammers, liners, frogs 1 stainless steels 300 series 18cr8ni 302, 304, 308, 316 and all l grades 2 2 1 3 corrosionresistant and high temperature. This specification covers seam welded ferriticmartensitic stainless steel pipe intended for abrasive and general corrosion service. Welding duplex and superduplex stainless steel lasgroep regio.
How to weld duplex stainless steel rolled alloys, inc. Pdf on may 15, 20, hans astrom and others published welding of duplex stainless steel find, read and cite all the research you need on. The grade uns s31803 has now reached the third place in. Selection of a joint design should accommodate the following guidelines. Tig is strongly recommended for root passes in onesided welding. Since the introduction, new processes, materials and classifications have been accepted. Heat treated 410 has mechanical properties comparable to the engineering alloy steel aisi 4, coupled with the additional benefit of good corrosion resistance. By choosing esab as their partner, customers know they have the technical support of one of the largest suppliers of welding consumables in the world. If you are welding fillet welds, they must be qualified by w.
For example, the importance of having sufficient nitrogen in the duplex stainless. Astm a1053 a1053m 122017 standard specification for. Welding highlights welding guide for sandvik duplex. In laser beam welding, high intensity heat source is used which causes high cooling rate after welding process 23. Market development programs cooperation with consumers, endusers and allied organizations technical brochures and training seminars to explain the advantages. Ferrite control in duplex stainless steel weld metal. Duplex stainless steels dss have somewhat different welding requirements than ii. This guide is intended to provide information which may be used to avoid, or at least minimize, difficulties in welding. Duplex stainless steels are unrivalled in a large number of applications in the temperature range 50 c to 250 c where a combination of corrosion resistance and mechanical strength is required.
The weld metal nitrogen content of austenitic stainless steel was found to be a function of the welding variables ref. Weld failure analysis of 2205 duplex stainless steel. About half of the nickel content of ss304 is replaced with alloy additions of manganese and nitrogen. The pipes are classified according to sizes, from nps 2 to nps 36. We normally suggest that when developing a weld procedure it is critical to test the corrosion resistance, the impact toughness, and the ferriteaustenite mix in the weld qualification. It is the most widely used of the hardenable stainless steels. Chapter 1 contains general requirements for austenitic and duplex stainless steels. This guide covers four chapters pertaining to materials and welding for stainless steels. In tube applications, for example, duplex s higher. Results of laser welding process have been compared with that of tungsten inert gas tig welding process. Weldability and jointability of duplex stainless steels youtube. Duplex stainless steels are a combination of austenite and ferrite, and some grades employ nitrogen as an alloying ingredient which promotes austenite formation in welds and improves toughness. Physical and chemical phenomena influencing slag detachability during welding p. Good procedures must be developed for welding, forming, machining and heat treatment.
The stainless was a solid piece of 4 round that was drilled out 212 and threaded, leaving approx 34 side wall. Welding duplex stainless steel plate sandmeyer steel. It is not prequalified, so it must be qualified by testing. I believe the stainless is 304 and the carbon steel is a36. Hardness varies in a similar manner, from relatively soft annealed austenitic stainless steel to extremely hard martensitic material such as that used for razor blades or ball bearings. Practical guidelines for the fabrication of duplex stainless steels. Welding technical guide getting the most out of your products. Duplex austenitic ferritic stainless steels comprise a large family ranging from the lower alloyed lean grades, via the widely used 22%cr grades to the highly alloyed. Good stainless steel practice is the basis for welding duplex and superduplex grades. Dec 04, 2009 the welding characteristics of duplex stainless steels are much more sensitive to minor withingrade variations in chemistry or processing than are austenitic stainless steels.
The families of stainless steel used for structural sections and available product. Aisc live webinars american institute of steel construction. In addition to the improved corrosion resistance compared with the 300 series stainless steels duplex steels also have higher strength. The duplex stainless steels are finding increased use in industry and the information contained in this guide will be most useful. Softening due to martensite tempering in the subcriti.
The low carbon provides resistance to sensitization during welding and other thermal processes. Welder test and qualification for duplex stainless steel pipe 6g position duration. Welding duplex and superduplex stainless steel an update of the guide for industry by l van nassau, lincolh smitweld, the netherlands, h. Welding technical guide getting the most out of your. Nowadays, duplex stainless steel is a well recognized steel grade. Pdf welding of duplex stainless steel ijsrd international. The best steels to use for this purpose are the high nickel austenitic steels such as the 6% mo grades.
Pdf welding of duplex stainless steel researchgate. The macrographs of the top and cross 5 sectional views of the laser beam welded joint produced by the abovementioned. Welding variable effects on weld shape in electron beam welding of steels p. Page 129 practical aspects for production welding and. Duplex stainless steels are about twice as strong as regular austenitic or ferritic stainless steels. Kotecki introduction duplex stainless steels in wrought or cast form, when they reach the user, consist of a microstructure of approxi.
Because welding duplex stainless steel is not foolproof it is important to perform quality checks. This paper discusses good duplex and superduplex stainless steel practice. Duplex stainless steels have significantly better toughness and ductility than ferritic grades. The use of duplex stainless steels dsss is steadily increasing. Nominal sizes are nps 2 to nps 36 inclusive, with nominal average wall thickness up. For many uses where joining is needed, gas tungsten arc welding gtaw is one of the most important joining methods for dsss. Always use a recommended welding product duplex stainless steel weld fillers are slightly overalloyed compared to the base material composition of consumables is chosen to produce correct austeniteferrite balance in duplex stainless steel welds. After that the 4th duplex conference has been held glasgow 1994. The piece of a36 is 12 thick plate with a 212 hole to line up with the stainless.
The goal in welding any duplex stainless steel is to obtain fusion and heat affected zones having the excellent corrosion resistance of the base metal. Duplex stainless steel welding stainless steel welding. Their properties and their suitability for welding. In addition, for duplex stainless steel welding, the ratio of ferrite to austenite may be difficult to control in the weld metal and heat affected zone. In 1992, the first issue of welding duplex and super duplex stainless steel a guide for industry by l. The welding guides have more detail on which test is. Duplex ss are not difficult to work with but they are different. In fact, duplex s yield strength is considerably superior to that of conventional stainless steels, allowing for lighter constructions, more compact system designs and less welding. Stainless steel structures in swimming pools are known to be prone to scc. Weldability and jointability of duplex stainless steels.