welding techniques

7/21/2019 Welding Techniques

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WELDING TECHNIQUES

This article will cover basic welding techniqes in !stic" welding#!

Before welding make a final check and remove consumable material. Remove the

cigarette lighter from you pocket. Check your machine to make sure it's on andadjusted to the approximate settings. Clean the joint. Clamp the rod in the stinger at

a 4 to !" degree angle. #arn those around you. $lace the rod about two inchesfrom the work. %djust your hood so that when you nod your head the hood will fall

over your face.

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&trike the arc using the tip of the rod on the surface using a wrist motion just like

when you strike a wooden match. #hen the arc is struck lift the rod about ()*+above the base material. ,f the rod +sticks+ snap the stinger backward from the

direction of the work. Become light handed. $ractice on scrap pieces.

$ro%er Welding Techniqes

Run a practice bead. &trike an arc moving the welding rod across the plate at a

uniform speed and at an incline of about -" degrees in the direction of travel. % righthanded person usually welds from left to right. &teady your elbow against your body

the table or the work. se the free hand as needed to control the stinger. Run beads

that consume the entire rod. /et the arc penetrate the base metal and deposit thefiller metal 0from the rod1 into the joint.

Continue to strike arcs and run beads across the joint making proper adjustmentsuntil you start and stop as desired with no problems. 2o further adjustments should

be needed. Burn the rod down to about ( and ()-+ from the end. 3ne welding rodusually produces a weld about (+ long.

To contine or to restart the bead&

#hen you stop there is a +crater.+ Chip the slag and restrike the arc a little bitahead of the crater and then run the bead. ,n time this method will produce uniform

welds of high strength without trapping any slag in the bead that cause defects. %tthe end of a weld or when the rod is used up pause slightly to fill the crater then pull

the rod away. Chip the slag and inspect the weld.

5ood welds are dependent on five techni6ues7 correct amperage setting8 correct arc

length8 correct rod selection and angle to the work8 correct travel speed8 andwelding rods that have been stored and maintained properly.

#hen electrodes absorb moisture from the atmosphere they must be dried in orderto restore the ability to deposit 6uality welds. 9lectrodes with too much moisture

cause unexplained cracking poor operating characteristics and porosity. ,f you'veexperienced these conditions it usually is due to your storage methods or redrying

procedures. %ll electrodes even those outside of the +stick+ category must be storedand then dried to the right level to work well. 9ven a small amount of moisture in low

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hydrogen electrodes for example can lead to major weld problems such as internalporosity and weld cracking.

:oo little amperage causes a weak arc that is hard to strike. :oo much amperagecauses a large crater or a flat bead with excessive spatter.

%n arc that is too short will make the rod stick. :oo long and large drops of meltedmetal will drip off the rod and it will tend to +blow' and spatter. % long arc also

produces uneven bead with poor penetration.

:he rod angle affects the penetration. %n important welding techni6ue is holding the

rod nearly perpendicular to the joint increase penetration but can cause slag to gettrapped in the weld. /owering the rod too flat or low lessens the penetration and

causes ripples.

&peed affects the amount of rod deposited and the uniformity of the bead. Correct

speed produces about (+ of weld per rod. :ravel too fast and it makes a thin beadwith little penetration. :oo slow lets the bead build up with edges that overlap the

base metal. :oo slow of travel on thin metal will blow a hole through.

&ee chart for recommended welding rod storage and temperature.

%ll of the electrodes listed below should be stored dry at room temp when in

unopened cartons

Electrode

Classi'ication

(eco))ended

Storage o%en

*o+es

Holding ,ven (econditioning

9;;(" <ry = room temp 2ot Recommended 2ot done

9;;(( <ry = room temp 2ot Recommended 2ot done

9;;(- <ry = room temp 2ot Recommended 2ot done

9;;(> <ry = room temp 2ot Recommended 2ot done

9;;(4 (" -"" ? (" -"" ? -" >"" ? ( hr.

9;;-" (" -"" ? (" -"" ? -" >"" ? ( hr.

9;;-4 (" -"" ? (" -"" ? -" >"" ? ( hr.

9;;-@ (" -"" ? (" -"" ? -" >"" ? ( hr.

9A" or @"( -" 4" ? (" -"" ? "" A"" ? ( hr.

9A" or @"(A -" 4" ? (" -"" ? "" A"" ? ( hr.

9@"(* -" 4" ? (" -"" ? "" A"" ? ( hr.

9@"-* -" 4" ? (" -"" ? "" A"" ? ( hr.

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9*" or !"( -" 4" ? -"" -" ? A"" @"" ? ( hr.

9*" or !"(A -" 4" ? -"" -" ? A"" @"" ? ( hr.

9*" or !"(* -" 4" ? -"" -" ? A"" @"" ? ( hr.

9!" (-"( -" 4" ? -"" -" ? A" @" ? ( hr.

9!" (-"(A -" 4" ? -"" -" ? A" @" ? ( hr.

9!" (-"(* -" 4" ? -"" -" ? A" @" ? ( hr.

9 ;;;( or

(A

-" 4" ? (" -"" ? 4" ? ( hr.

&tainless -" 4" ? (" -"" ? 4" ? ( hr.

#hen being reconditioned electrodes should not be baked for more than 4

hours and should be kept at temp for at least >" minutes. Baking more than >

times is not recommended.

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Ti%s on Handling Welding (ods

#elding rods get no respect. 3ut in the field ,'ve seen guys throwing "lb. rod cansfrom the truck onto the ground torching cans open diagonally beating the wrong


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end open with a chipping hammer and every other conceivable tool and leavingopen rod cans out in the open.

Let2s loo" at what2s wrong with each3

?irst and foremost %/#%& open the +right+ end of the can. &ome cans and boxes

even say +open other end+ or +don't open this end+ or +the other end moron.+ 0lastone made up by me.1 :he reason you need to open the right end is because you can

damage the flux coating. ou want to open it on the side where the rod is bare for

the stinger or electrode holder. :here's a lot less chance of damaging the flux thatway. @"(* is very prone to flux damage while A"(" is a lot tougher.

Dost guys out in the field aren't gonna' be thinking about the welding rods inside the

can as they toss them from the truck to the ground. #hen the cans get manhandledthe flux gets jarred loose on the welding rods inside. ,t's bad enough when the flux

gets chipped off the end of the rod flux chipped from the middle and you can prettymuch kiss that rod goodbye. ,t's worse if you don't realiEe it's chipped because right

in the middle of a good weld you'll suddenly be welding with no flux. 2o flux e6uals

no shielding from the atmosphere and that e6uals a garbage weld.

ou can use a lot of different ways to open rod cans out in the field if you are careful.,'ve even used the $>* C ration can opener , had in the army.,f you use an

oxygen)acetylene torch you need to be real careful not to burn the flux on the rodsinside.

ou can open a rod can with a chipping hammer but it's not advisable. ou gotta' be

sure and hit it just right at the edge of the can. ou should hit the edge with thehammer followthrough swinging away from the can not striking down into the can

at the top. 0,'m sure the electrode manufacturers are cringing when they read this1

3f course the best way is whatever the can is designed for some of them open like asardine can but a lot of times it doesn't work so you gotta' improvise.

/eaving open cans out allows moisture to get into the flux. Doisture in the flux cancause porosity or worm holes in the weld. Rods should be stored in a proper oven or

unheated container if they don't need the moisture protection. @"(* needs an ovenwhile A"(" doesn't need the heat but still needs to be kept protected.

Heat Treatent of Standard Steels



Heat/Treating De'initions :his glossary of heattreating terms has been adoptedby the %merican ?oundrymen's %ssociation the %merican &ociety for Detals the

%merican &ociety for :esting and Daterials and the &ociety of %utomotive 9ngineers.&ince it is not intended to be a specification but is strictly a set of definitions

temperatures have purposely been omitted.

4ging& <escribes a timetemperaturedependent change in the properties of certainalloys. 9xcept for strain aging and age softening it is the result of precipitation froma solid solution of one or more compounds whose solubility decreases with

decreasing temperature. ?or each alloy susceptible to aging there is a uni6ue rangeof timetemperature combinations to which it will respond.

4nnealing& % term denoting a treatment consisting of heating to and holding at asuitable temperature followed by cooling at a suitable rate used primarily to soften

but also to simultaneously produce desired changes in other properties or inmicrostructure. :he purpose of such changes may be but is not confined to

improvement of machinability 8 facilitation of cold working8 improvement ofmechanical or electrical properties8 or increase in stability of dimensions. :he time

temperature cycles used vary widely both in maximum temperature attained and incooling rate employed depending on the composition of the material its condition

and the results desired. #hen applicable the following more specific process namesshould be used7 Black %nnealing Blue %nnealing Box %nnealing Bright %nnealing

Cycle %nnealing ?lame %nnealing ?ull %nnealing 5raphitiEing ,ntermediate%nnealing ,sothermal %nnealing $rocess %nnealing Fuench %nnealing and

&pheroidiEing . #hen the term is used without 6ualification full annealing is implied.#hen applied only for the relief of stress the process is properly called stress

relieving.

*lac" 4nnealing& Box annealing or pot annealing used mainly for sheet strip or

wire.

*le 4nnealing& Geating hotrolled sheet in an open furnace to a temperature

within the transformation range and then cooling in air to soften the metal. :heformation of a bluish oxide on the surface is incidental.

*o+ 4nnealing& %nnealing in a sealed container under conditions that minimiEeoxidation. ,n box annealing the charge is usually heated slowly to a temperature

below the transformation range but sometimes above or within it and is then cooledslowly8 this process is also called +close annealing+ or +pot annealing.+

*right 4nnealing& %nnealing in a protective medium to prevent discoloration of thebright surface.

C5cle 4nnealing& %n annealing process employing a predetermined and closelycontrolled timetemperature cycle to produce specific properties or microstructure.

1la)e 4nnealing& %nnealing in which the heat is applied directly by a flame.

1ll 4nnealing& %ustenitiEing and then cooling at a rate such that the hardness of

the product approaches a minimum.



Gra%hiti6ing& %nnealing in such a way that some or all of the carbon is precipitatedas graphite.

Inter)ediate 4nnealing& %nnealing at one or more stages during manufacture andbefore final thermal treatment.

Isother)al 4nnealing& %ustenitiEing and then cooling to and holding at atemperature at which austenite transforms to a relatively soft ferritecarbide

aggregate.

$rocess 4nnealing& %n imprecise term used to denote various treatments that

improve workability. ?or the term to be meaningful the condition of the material andthe timetemperature cycle used must be stated.

Qench 4nnealing& %nnealing an austenitic alloy by &olution Geat :reatment.

S%heroidi6ing& Geating and cooling in a cycle designed to produce a spheroidal or

globular form of carbide.

4ste)%ering& Fuenching from a temperature above the transformation range in a

medium having a rate of heat abstraction high enough to prevent the formation of

hightemperature transformation products and then holding the alloy untiltransformation is complete at a temperature below that of pearlite formation and

above that of martensite formation.

4steniti6ing& ?orming austenite by heating into the transformation range 0partialaustenitiEing 1 or above the transformation range 0complete austenitiEing 1. #hen

used without 6ualification the term implies complete austenitiEing .

*a"ing& Geating to a low temperature in order to remove entrained gases.

*ling& % treatment of the surface of ironbase alloys usually in the form of sheetor strip on which by the action of air or steam at a suitable temperature a thin blue

oxide film is formed on the initially scalefree surface as a means of improvingappearance and resistance to corrosion. :his term is also used to denote a heat

treatment of springs after fabrication to reduce the internal stress created by coilingand forming.

Carbon $otential& % measure of the ability of an environment containing activecarbon to alter or maintain under prescribed conditions the carbon content of the

steel exposed to it. ,n any particular environment the carbon level attained willdepend on such factors as temperature time and steel composition.

Carbon (estoration& Replacing the carbon lost in the surface layer from previousprocessing by carburiEing this layer to substantially the original carbon level.

Carbonitriding& % casehardening process in which a suitable ferrous material isheated above the lower transformation temperature in a gaseous atmosphere of such

composition as to cause simultaneous absorption of carbon and nitrogen by thesurface and by diffusion create a concentration gradient. :he process is completed

by cooling at a rate that produces the desired properties in the workpiece .



Carbri6ing& % process in which carbon is introduced into a solid ironbase alloy byheating above the transformation temperature range while in contact with a

carbonaceous material that may be a solid li6uid or gas. CarburiEing is fre6uentlyfollowed by 6uenching to produce a hardened case.

Case&

(1 :he surface layer of an ironbase alloy that has been suitably altered in

composition and can be made substantially harder than the interior or core by a

process of case hardening

-1 the term case is also used to designate the hardened surface layer of a piece ofsteel that is large enough to have a distinctly softer core or center

Ce)entation& :he process of introducing elements into the outer layer of metalobjects by means of hightemperature diffusion.

Cold Treat)ent& 9xposing to suitable subEero temperatures for the purpose of

obtaining desired conditions or properties such as dimensional or microstructuralstability. #hen the treatment involves the transformation of retained austenite it isusually followed by a tempering treatment.

Conditioning Heat Treat)ent& % preliminary heat treatment used to prepare a

material for a desired reaction to a subse6uent heat treatment. ?or the term to bemeaningful the treatment used must be specified.

Controlled Cooling& % term used to describe a process by which a steel object is

cooled from an elevated temperature usually from the final hotforming operation ina predetermined manner of cooling to avoid hardening cracking or internal damage.

Core&

(1 :he interior portion of an ironbase alloy that after case hardening is substantially

softer than the surface layer or case

-1 the term core is also used to designate the relatively soft central portion of certainhardened tool steels

Critical Range or Critical :emperature Range 7 &ynonymous with :ransformation

Range which is preferred.

C5aniding& % process of case hardening an ironbase alloy by the simultaneous

absorption of carbon and nitrogen by heating in a cyanide salt. Cyaniding is usuallyfollowed by 6uenching to produce a hard case.

Decarbri6ation& :he loss of carbon from the surface of an ironbase alloy as theresult of heating in a medium that reacts with the carbon.

Drawing& <rawing or drawing the temper is synonymous with :empering which is

preferable.



Etectic 4llo5& :he alloy composition that freeEes at constant temperature similarto a pure metal. :he lowest melting 0or freeEing1 combination of two or more metals.

:he alloy structure 0homogeneous1 of two or more solid phases formed from theli6uid eutectically .

Hardenabilit5& ,n a ferrous alloy the property that determines the depth and

distribution of hardness induced by 6uenching.

Hardening& %ny process of increasing hardness of metal by suitable treatment

usually involving heating and cooling. %lso7 &ee %ging

Hardening7 Case& % process of surface hardening involving a change in thecomposition of the outer layer of an ironbase alloy followed by appropriate thermal

treatment. :ypical casehardening processes are CarburiEing CyanidingCarbonitriding and 2itriding .

Hardening7 1la)e& % process of heating the surface layer of an ironbase alloyabove the transformation temperature range by means of a hightemperature flame

followed by 6uenching.

Hardening7 $reci%itation& % process of hardening an alloy in which a constituent

precipitates from a supersaturated solid solution. &ee also %ging.

Hardening7 Secondar5& %n increase in hardness following the normal softening thatoccurs during the tempering of certain alloy steels.

Heating7 Di''erential& % heating process by which the temperature is made to vary

throughout the object being heated so that on cooling different portions may havesuch different physical properties as may be desired.

Geating ,nduction7 % process of local heating by electrical induction.

Heat Treat)ent& % combination of heating and cooling operations applied to a

metal or alloy in the solid state to obtain desired conditions or properties. Geating forthe sole purpose of hot working is excluded from the meaning of this definition.

Heat Treat)ent7 Soltion& % treatment in which an alloy is heated to a suitable

temperature and held at this temperature for a sufficient length of time to allow a

desired constituent to enter into solid solution followed by rapid cooling to hold theconstituent in solution. :he material is then in a supersaturated unstable state and

may subse6uently exhibit %ge Gardening.

Ho)ogeni6ing& % hightemperature heattreatment process intended to eliminateor to decrease chemical segregation by diffusion.

Isother)al Trans'or)ation& % change in phase at constant temperature.

8alleabli6ing& % process of annealing white cast iron in which the combined carbonis wholly or in part transformed to graphitic or free carbon and in some cases part

of the carbon is removed completely. &ee :emper Carbon.



8araging& % precipitation hardening treatment applied to a special group of ironbase alloys to precipitate one or more intermetallic compounds in a matrix of

essentially carbonfree martensite .

8arte)%ering& % hardening procedure in which an austenitiEed ferrous workpiece is

6uenched into an appropriate medium whose temperature is maintained substantially

at the Ds of the workpiece held in the medium until its temperature is uniformthroughout but not long enough to permit bainite to form and then cooled in air. :hetreatment is followed by tempering.

Nitriding& % process of case hardening in which an ironbase alloy of special

composition is heated in an atmosphere of ammonia or in contact with nitrogenous

material. &urface hardening is produced by the absorption of nitrogen without6uenching.

Nor)ali6ing& % process in which an ironbase alloy is heated to a temperatureabove the transformation range and subse6uently cooled in still air at room

temperature.

,verheated& % metal is said to have been overheated if after exposure to an unduly

high temperature it develops an undesirably coarse grain structure but is notpermanently damaged. :he structure damaged by overheating can be corrected by

suitable heat treatment or by mechanical work or by a combination of the two. ,nthis respect it differs from a Burnt structure.

$atenting& % process of heat treatment applied to medium or highcarbon steel in

wire making prior to the wire drawing or between drafts. ,t consists in heating to atemperature above the transformation range followed by cooling to a temperature

below that range in air or in a bath of molten lead or salt maintained at a

temperature appropriate to the carbon content of the steel and the propertiesre6uired of the finished product.

$reheating& Geating to an appropriate temperature immediately prior toaustenitiEing when hardening high hardenability constructional steels many of the

tool steels and heavy sections.

Qenching& Rapid cooling. #hen applicable the following more specific terms

should be used7 <irect Fuenching ?og Fuenching Got Fuenching ,nterruptedFuenching &elective Fuenching &lack Fuenching &pray Fuenching and :ime

Fuenching.

Direct Qenching& Fuenching carburiEed parts directly from the carburiEingoperation.

1og Qenching& Fuenching in a mist.

Hot Qenching& %n imprecise term used to cover a variety of 6uenching proceduresin which a 6uenching medium is maintained at a prescribed temperature above (A"

degrees ? 0@( degrees C1.



Interr%ted Qenching& % 6uenching procedure in which the workpiece is removedfrom the first 6uench at a temperature substantially higher than that of the

6uenchant and is then subjected to a second 6uenching system having a differentcooling rate than the first.

Selective Qenching& Fuenching only certain portions of a workpiece .

Slac" Qenching& :he incomplete hardening of steel due to 6uenching from the

austenitiEing temperature at a rate slower than the critical cooling rate for the

particular steel resulting in the formation of one or more transformation products inaddition to martensite .

S%ra5 Qenching& Fuenching in a spray of li6uid.

Ti)e Qenching& ,nterrupted 6uenching in which the duration of holding in the6uenching medium is controlled.

Soa"ing& $rolonged heating of a metal at a selected temperature.

Stabili6ing Treat)ent& % treatment applied to stabiliEe the dimensions of a

workpiece or the structure of a material such as

(1 before finishing to final dimensions heating a workpiece to or somewhat beyond

its operating temperature and then cooling to room temperature a sufficient numberof times to ensure stability of dimensions in service

-1 transforming retained austenite in those materials that retain substantial amountswhen 6uench hardened 0see cold treatment1

>1 heating a solutiontreated austenitic stainless steel that contains controlled

amounts of titanium or niobium plus tantalum to a temperature below the solutionheattreating temperature to cause precipitation of finely divided uniformlydistributed carbides of those elements thereby substantially reducing the amount of

carbon available for the formation of chromium carbides in the grain boundaries onsubse6uent exposure to temperatures in the sensitiEing range.

Stress (elieving& % process to reduce internal residual stresses in a metal object by

heating the object to a suitable temperature and holding for a proper time at that

temperature. :his treatment may be applied to relieve stresses induced by casting6uenching normaliEing machining cold working or welding.

Te)%er Carbon& :he free or graphitic carbon that comes out of solution usually in

the form of rounded nodules in the structure during 5raphitiEing or DalleabliEing .

Te)%ering& Geating a 6uenchhardened or normaliEed ferrous alloy to atemperature below the transformation range to produce desired changes in

properties.

Doble Te)%ering& % treatment in which 6uench hardened steel is given two

complete tempering cycles at substantially the same temperature for the purpose of



ensuring completion of the tempering reaction and promoting stability of theresulting microstructure.

Sna% Te)%er& % precautionary interim stressrelieving treatment applied to highhardenability steels immediately after 6uenching to prevent cracking because of

delay in tempering them at the prescribed higher temperature.

Te)%er *rittleness& Brittleness that results when certain steels are held within or

are cooled slowly through a certain range of temperatures below the transformation

range. :he brittleness is revealed by notchedbar impact tests at or below roomtemperature.

Trans'or)ation (anges or Trans'or)ation Te)%eratre (anges& :hose

ranges of temperature within which austenite forms during heating and transformsduring cooling. :he two ranges are distinct sometimes overlapping but never

coinciding. :he limiting temperatures of the ranges depend on the composition of thealloy and on the rate of change of temperature particularly during cooling.

Trans'or)ation Te)%eratre& :he temperature at which a change in phaseoccurs. :he term is sometimes used to denote the limiting temperature of a

transformation range. :he following symbols are used for iron and steels7

%ccm H,n hypereutectoid steel the temperature at which the solution of cementite in

austenite is completed during heating

%c( H :he temperature at which austenite begins to form during heating

%c> H :he temperature at which transformation of ferrite to austenite is completedduring heating

%c4 H :he temperature at which austenite transforms to delta ferrite during heating

%e( %e> %ecm %e4 H :he temperatures of phase changes at e6uilibrium

%rcm H,n hypereutectoid steel the temperature at which precipitation of cementite

starts during cooling

%r( H :he temperature at which transformation of austenite to ferrite or to ferriteplus cementite is completed during cooling

%r> H :he temperature at which austenite begins to transform to ferrite duringcooling

%r4 H :he temperature at which delta ferrite transforms to austenite during cooling

Ds H :he temperature at which transformation of austenite to martensite starts

during cooling

Df H :he temperature during cooling at which transformation of austenite to

martensite is substantially completed



The !portance of Low"H# Rods in a Welding $o%



/owhydrogen welding rods are the backbone of structural welding. Inown as +lowhy+ to welders in the field this versatile electrode is manufactured to contain less

than ".AJ of moisture in the covering and is re6uired by currently acceptablewelding standards and procedures to be stored in an environment that maintains

factory 6uality dryness. Its low h5drogen content ensres a s)ooth7 strongweld that is ver5 dctile7 )a"ing it the welding rod o' choice 'or strctral

welding 9obs#

,t is well known that prior to beginning a structural welding job that lowhydrogen

electrodes must be conditioned properly to avoid damaging defects in the welds. 3neof the ways utiliEed to protect the lowhydrogen coating is to double coat using a

titania layer to help avoid defects when low hydrogen deposits are re6uired. But

problems such as porosity hydrogen embrittlement lack of fusion and cracking canresult if standard low hydrogen rods are not stored according to the manufacturer's

specifications.

&pecifically hydrogen can adversely affect a weld and some steels under a variety ofconditions. :he primary source for the presence of hydrogen is moisture in the

electrode coating picked up through exposure to the atmosphere. ?or this reasonwith any welding job proper storage handling and treatment of low hydrogen

electrodes is critical to prevent a defective weld. :his is especially important in theconstruction and erection of multiple story buildings which rely for their support and

inner structure on welded steel beams.

% defective weld can result in the collapse of a building or during subse6uent

inspection rejection of the weld. :his re6uires rebuilding a portion of the metal innerstructure of a skyscraper or other building sometimes at a cost of many millions of

dollars.

#elding electrodes are manufactured to be within acceptable moisture limitsconsistent with the type of covering and strength of the weld metal to be used with

the electrode. :hey are then packaged in a container which has been designed to

provide the degree of moisture protection considered necessary by the industry forthe type of covering involved. % common mistake is opening the container from the

wrong end or tossing them around which can crack the low hydrogen coating on thewelding rods rendering them useless.

#ith any welding job ,t is very important to maintain your rods or electrodes within atemperature range of (""K? and >""K?. :his temperature range has been determined

by the welding industry to be ade6uate to prevent atmospheric moisture fromentering the welding rod coating and subse6uently entering the weld during the

welding process.

,n particular maintaining lowhydrogen electrodes in a dry consistently heatedenvironment is a must. %sk any welding professional and they will recommend thatlowhydrogen electrodes be stored in a rod oven. %ny other rudimentary method

such as utiliEing an old refrigerator or microwave with a ("" watt light bulb islaughable and is in no way acceptable for today's welding professional.

Storing and Re"dr#ing Electrodes



&hielded Detal %rc #elding 0&D%#1 electrodesmust be properly stored in order to deposit

6uality welds. #hen electrodes become absorbmoisture from the atmosphere they must be

dried in order to restore the ability to deposit6uality welds. 9lectrodes with too much

moisture may lead to cracking or porosity.3perational characteristics may be affected as

well. ,f youLve experienced unexplained weldcracking problems or if the electrode arc

performance may have deteriorated it may bedue to your storage methods or redrying procedures.

Save on Disconted Welding (od ,vens

%ll electrodes must be dried to the right level to perform properly. 9ven a small

amount of moisture in low hydrogen electrodes can lead to major weld problemssuch as internal porosity weld cracking or poor operating characteristics. #e will lookat three different types of electrodes7

:# Low H5drogen Electrodes

Storing and e+%osre li)its

&D%# electrodes with low hydrogen coatings such as 9@"(* and 9*"(*C> must bekept very dry since hydrogen induced cracking can easily occur especially in steels

that are *"""" psi and higher yield strengths. :o keep these electrodes dry during

storage and to prevent welding defects here are some suggestions7

• $urchase these electrodes in hermetically sealed containers which provide

excellent protection against moisture pickup.

• <o not open the hermetically sealed containers until the electrode is needed

for use.

• #hen the cans are opened electrodes that will not be immediately used

should be placed in a cabinet at -" degrees to >"" degrees 0(-" M ("

degrees C1.

• 9lectrodes should be supplied to welders in 6uantities that can be consumed

within time limits that are dependent on the electrode type and strength level.

?or example standard 9@"(* electrodes can be safely be exposed to the

atmosphere for 4 hours whereas standard 9(("(* electrodes are restricted to

only N hour.

(e/dr5ing

#hen the hermetic seal is broken 0either deliberately such as when a can is opened

or accidentally as when a can is punctured1 a can of low hydrogen &D%# electrodesmust be redried. #hen the electrodes have been exposed to the atmosphere for

period of a few days the electrode can be redried. :he following redryingprocedures should be used7


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• :o redry electrodes should be removed from the can and placed in suitable

oven. :he electrodes should be spread out in the oven so that all electrodes

will reach the drying temperature. :he can of electrodes should not be put inthe oven8 the cardboard liners can char and the temperature of the

electrodes will not be uniform.

• #hen the electrodes are initially placed in the oven the temperature should

not be greater than half the redrying temperature. :he electrodes should beheld at that temperature for N hour before heating the electrode to the final

temperature.

• ?or mild steel low hydrogen electrodes governed by %#& %.( 0such as

9@"(*1 the final redrying temperature is typically ""*"" degrees ?. ?orlow alloy electrodes governed by %#& %. the final redrying temperature

should be @""*"" degrees ?. :he manufacturerLs recommendations should befollowed.

• 3ne hour at the listed final temperature is satisfactory. <o not dry electrodes

at higher temperatures. %lso several hours at a lower temperature is not

e6uivalent to using the specified re6uirements. Doisture becomes chemicallybonded 0absorbed1 to the electrode coating and those chemical bonds must

be broken at the proper temperature for the proper length of time or theelectrode can be damaged.

• %ny electrode should be discarded if excessive redrying causes the coating to

become fragile and flake or break off while welding. 3r dispose of the

electrode if there is a noticeable difference in handling or arc characteristicssuch as insufficient arc force.

;# 4stenitic Stainless Steel Electrodes


%ustenitic &tainless &teel for &D%# must be kept dry. :ypically the first problem that

will be noticed with welding with such electrodes that have been contaminated withmoisture will be weld porosity. 3ther operational characteristics may also be affected.:o keep these electrodes dry during storage here are some suggestions7

<# Non/low h5drogen electrodes


&D%# electrodes such as 9A"(" and 9@"(4 are not low hydrogen and yet it isimportant that these electrodes also be properly stored. nlike the low hydrogen

electrodes that always must be kept dry some of the nonlow hydrogen electrodesneed some moisture in the coatings in order to perform properly. ,f these electrodes

are too dry they may not function properly. %lternative excessively moist electrodesmay cause other problems. :he following procedures should be followed7

• &tore these non low hydrogen electrodes from the freshly opened containers

in heated cabinets at ("" degrees M (-" degrees ? 04" M " degrees C1.

• <o not use higher temperatures particularly for electrodes from the O?ast

?reeEeP group which includes /incoln &hield%rcQ and certain types of

?leetweldQ electrodes.



(e/dr5ing

?ollow these simple storage exposure and redrying techni6ues to ensure the

highest 6uality welds as well as the best operational characteristics from your &D%#electrodes.

Reprinted from /inclonelectric.com

TIG WELDING SU$$LIES



<ifferent kinds of :,5 welding supplies and e6uipment available. :hey often include ahand or foot pedal to control the heat. :hey come in both %C and <C current. Both

water and air cooled torches are available. 9ach type of machine carries differentamperage ratings and run on single or threephase power. Consult the appropriate

guides)manuals for the type of machine and torch to use.

Chec" ot or TIG Welding Storage ,vens

?or :,5 welding you will need electrical power shielding gas and a water inlet and

outlet for cooling. $ersonal protective gear especially gloves shields and eyeglasses

should be worn to protect the weldor.

%rgon gas is supplied in steel cylinders similar to oxygen)acetylene cylinders. se atwostage regulator for better gas flow control. 0:he rate of flow re6uired depends on

the kind and thickness of the metal to be welded.1

:remendous heat from the arc and high electric current may make watercooling

necessary. :he cooling water and the :,5 torch must kept be clean and wellmaintained to prevent damage to the e6uipment. ,n some cases filtered water

instead of tap water may be re6uired.

:,5 welding machines are usually rated as light industrial or heavy duty. :hey run

on both %C and <C current. Dost machines are capable of :,5 and &tick welding andthey work on single or >phase power and have varied amp settings. #hen

purchasing a :,5 welding machine package all you need is a bottle of shielding gasto get started.

Dost light duty packages feature a :,5 output adjustment with the remote foot or

fingertip control8 an %C output for superior aluminum welding8 a <C output for mildand stainless steel Cost range for a light duty package runs (-"" to -4"".

,ndustrial duty packages include a cart for the water cooler8 microstart technology

for stateoftheart low amperage starting8 and watercooled torch connections. Dostoutfits include stickwelding capabilities with 9A"(" and 9@"(* electrodes. &ome

machines have advanced control panels that integrate :,5 +pulsing+ and triggercontrols into the machine. Dost industrial duty machines have an interior automatic

cooling fan. :hese packages usually range in cost from -""" to """.

3ptional or separate :,5 supplies can include %1 an undercarriage for the machine

itself. ,t has a single gas cylinder platform bracket with a chain to accommodate A to

! inch diameter gas cylinders. B1 Gand amperage controls that fasten to the :,5torch for convenient thumb control. C1 % water solenoid kit that enables use of tapwater for an economical watercooled system. C1 Sarious air and watercooled :,5

torches are available.

,n addition there are :,5 ovens which are designed to store a combination of

welding consumables. :hese mixeduse ovens are capable of maintaining dryness infiller wire electrodes and fluxcored wire.

http://www.rodovens.com/models/mig_tig_storage_ovens.htm






Welding 1l+



:here is some mystery involved with the term !welding 'l+#! Gopefully this articlewill give you a better understanding of what flux is what its functions are and how

to store flux and consumable stick and wire electrodes.

1sion =S# Non 1sion&#hen soldering copper or brass a nonfusion process the area has to be cleaned

first. :he most common chemical used for this is muriatic acid. %fter the joint or areato be soldered is cleaned the metal is evenly heated and the +flux+ is applied8 it'susually brushed on. #hen the metal is heated solder is added manually and the

metals become joined. 0:he same process holds true with +braEing.+ ,n braEing steelthe area is cleaned the metal is heated and the braEing rod is heated and dipped

into the can of +flux+ and used that way.1

Gowever +welding+ metals fusing them together re6uires more than just heating

the metals to be joined. #hen welding the base metals along with the welding rodor wire electrode need to be taken to high temperatures for fusion. :his causes

chemical reactions that do not exist at low or moderate temperatures.

1l+7 (od7 Gases 4nd Heat&:he electrode a coated rod or wire the base metal 0s1 and the heating action itselfreact chemically with the oxygen and nitrogen in the air. <uring the process the

metal must be protected from these reactions so the strength and integrity of thewelded joint can be assured. :herefore the stick or wire electrode and the flux it

provides cover the arc and the molten pool with a protective shield of gas and vapor.+&hielding the arc+ is the term most often used.

#ith welding rods and wire electrodes the +flux+ is applied in the factory. :he fluxhas several functions7

• ,t helps to clean the metals surfaces.

•

,t helps to join the filler metals to the base metals.• ,t provides a protective barrier against igniting.

• ,t helps with heat transfer from heat source to metal surface and it helps in

the removal of surface metal wastes.

• ,t also helps the deposits of metal from the electrode.

#ith any lowhydrogen or wire electrodes it is imperative to use proper storageprocedures. #elding rods and wire electrodes need to stay in their sealed container.

3nce opened and the electrode is exposed to the air 0even for a few hours in humidconditions1 they should be reconditioned and then stored in a rod oven until used.

0#hen in doubt always consult the manufacturer or suppliers recommendations.1

Rod3vens.com has a wide range of reconditioning and holding ovens in all siEesmodels and shapes. #e also carry unheated storage containers and replacement

parts for ovens. #e feature a >"day moneyback and guarantee ?R99 shipping to

your business.

http://www.rodovens.com/welding_articles/welding_rods.htm

http://www.rodovens.com/welding_articles/welding_electrodes.htm


http://www.rodovens.com/welding_articles/welding_rods.htm

http://www.rodovens.com/welding_articles/welding_electrodes.htm


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