7/21/2019 308 H Definition

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Q: I have a new fabrication project for furnace racks made with 304H stainless steel and the specificationssay to weld it with an E30H electrode! However" I already have some E30#E30$ stick electrodes and wantto know if I can use those instead% &hat is the difference between 30" 30$ and 30H% I actually have twobrands of E30 # E30$ electrodes" one type has a '()*+ after the 30 numbers and the other has a '(),+!&hat do those mean%

 A: First, note that an American Welding Society (AWS) E308 classification electrode is meant for welding Austenitic tyes of stainless steel! "herefore, this article will only address this tye! While Austenitic stainless steels are #ery common, thereare also Ferritic, $artensitic, %ule& and 'reciitation ardening tyes of stainless steels!

"he answer to your first uestion is no, an E308 * E308+ stainless steel electrode is not meant for use on an AS tye 30-.ase metal! /ou do need to use an E308 electrode! "he reason why will .e e&lained shortly! egarding your seconduestion, 13082 is a articular tye of stainless steel! t is tyically used to mae welding electrodes and used to 4oincommon tyes of austenitic stainless steels, such as 305, 306, 30- and 307! "he 12 and 1+2 designators indicate a secificcomosition of the electrode! $ore secifically, they refer to the car.on ercentage in the electrode, with 12 electrodes inthe high end and 1+2 electrodes in the low end of the electrodes car.on range! An E308 tye stainless steel electrode mustha#e a ma&imum of 0!089 .y weight of car.on ()! An E308 electrode howe#er, must ha#e at least 0!0-9, u to ama&imum of 0!089 ! ar.on content in the range of 0!0- ; 0!089 ro#ides higher tensile and cree strengths at ele#atedtemeratures! "hey are rimarily used in industrial euiment at high ser#ice temeratures (sometimes o#er 6,000<F(5,0=3<)! "herefore, an E308 electrode would .e the aroriate choice for your furnace rac ro4ect! on#ersely, anE308+ electrode can ha#e no more than 0!0-9 ! "he 1+2 tye electrodes are sometimes referred to as 1E+2 (e&tra low

car.on) tyes! "he lower car.on content hels minimi>e the damaging effects to the corrosion resistance of the heataffected >one (i!e! sensiti>ation) caused .y intergranular car.ide reciitation! "hey are most often used for weldments thatoerate in se#ere corrosi#e conditions at temeratures under 800<F (-6?<)

@ote that a articular electrode could, and often is, dual classified! t could .e classified as E308 * E308+ or as E308 *E308! "he 308 grade has a .roader car.on range, so if a articular electrodes car.on content falls within the tighter + or car.on le#el reuirements, it also meets the more general 308 reuirement! owe#er, you could ne#er ha#e an E308+ *E308 classified electrode, as one electrode could ne#er ha#e a car.on content that fits within .oth the low and high end ofthe car.on range! @ote also that the 12 and 1+2 car.on designators can aly to other tyes of austenitic stainless steels.esides E308! Some e&amles include E30=, E30=+, E350, E35, E35+, etc!

/our third uestion refers to the tye of coatings that are a#aila.le for stainless steel shielded metal arc (stic) electrodes!"here are three tyes of coating, a 1572, 152 and 15?2! A 1572 electrode has a lime .ased coating and is intended for %Bolarity only! "hey ha#e a lighter slag than the other two tyes and used for all osition welding, with some electrodes ofthis tye used rimarily for #ertical down welding! A 152 electrode has a titania or rutile .ased coating and can .e used with.oth % and A olarity! Electrode si>es of 7*36 in! (-!0 mm) and smaller are often used for all welding ositions! @ote,there is also a 162 classification, which is the same as a 152 tye coating, .ut for higher deosition alications and limitedto the flat and hori>ontal osition only! A 15?2 electrode has a silicaCtitania tye coating and is a modification of a 5 coating,in that some of the titania is relaced with silica! "hey also can .e used with .oth % and A olarity! Additional silicon inthe coating acts as a wetting agent, ha#ing the effect of increasing uddle fluidity! "his is articularly helful with stainlesssteel, as it tends to ha#e more of a sluggish weld .ead than car.on steel! Se#enteen tye electrodes roduce a flatter .eadrofile than the other two tyes and are often used for flat and hori>ontal osition welding! owe#er, electrode si>es of 7*36in! (-!0 mm) and smaller can .e used for all osition welding! @ote that with a #ertical u rogression, the slower free>ingslag will reuire more of a wea#e techniue than with a 5 tye electrode