(2) arc welding electrode

04/13/2304/13/23 ARC WELDING ELECTRODESARC WELDING ELECTRODES 11

ARC WELDING ARC WELDING ELECTRODEELECTRODE

NAFFAA. AL-ANEZINAFFAA. AL-ANEZI MECHANICAL INSPECTOR MECHANICAL INSPECTOR

OCTOBER 30,2005OCTOBER 30,2005


CONTENTS OF PRESENTATIONCONTENTS OF PRESENTATION

HISTORY OF ARC WELDING COATED HISTORY OF ARC WELDING COATED ELECTRODEELECTRODE

WHAT IS AN ELECTRODE ?WHAT IS AN ELECTRODE ? SIZE OF ELECRODE SIZE OF ELECRODE TYPES OF ELECTRODES TYPES OF ELECTRODES COATING OF ELECTRODES COATING OF ELECTRODES TYPES OF ELECTRODE COATING TYPES OF ELECTRODE COATING STORAGE AND DRYING OF STORAGE AND DRYING OF

ELECTRODES ELECTRODES TESTING OF ELECTRODES TESTING OF ELECTRODES


HISTORY OF ARC WELDING COATED HISTORY OF ARC WELDING COATED ELECTRODEELECTRODE

During first stage of work with metal arc During first stage of work with metal arc welding a bare electrode was in use which welding a bare electrode was in use which was producing brittleness in the welded was producing brittleness in the welded area and the weld was considerably weak. area and the weld was considerably weak. overheating effect on weld metal was overheating effect on weld metal was noticed as there was no arc stability.noticed as there was no arc stability.

To overcome these difficulties researchers To overcome these difficulties researchers developed a number of electrodes in 1907 developed a number of electrodes in 1907 that were covered with organic or mineral that were covered with organic or mineral materials which is known as coating or materials which is known as coating or flux. flux.


WHAT IS AN ELECTRODE ?WHAT IS AN ELECTRODE ?

The electrode may be defined as “it is metal of The electrode may be defined as “it is metal of which the sole purpose to carry the current and which the sole purpose to carry the current and sustain the electric arc between its tip and base sustain the electric arc between its tip and base metal as well as in some cases it melts and metal as well as in some cases it melts and supplies filler metal addition in the proposed supplies filler metal addition in the proposed joint.”joint.”

Electrode can be divided into two groups Electrode can be divided into two groups depending upon their functions which are given depending upon their functions which are given

below. below.

ELECTRODE

COSUMABLE NON CONSUMABLE


CONSUMABLE AND NON-CONSUMABLE AND NON-CONSUMABLE CONSUMABLE

The consumable electrodes refers to The consumable electrodes refers to conduct current from electrode conduct current from electrode holder to metal and supply filler holder to metal and supply filler metal to the joint, like in SMAW. metal to the joint, like in SMAW.

non-consumable electrodes are only non-consumable electrodes are only used to work as conductor carrying used to work as conductor carrying the current from electrode holder to the current from electrode holder to base metal, like in GMAW base metal, like in GMAW


SIZE OF ELECTRODESIZE OF ELECTRODE

THE SIZE OF ELECTRODE REFERS TO THE DIAMETER OF ITS CORE THE SIZE OF ELECTRODE REFERS TO THE DIAMETER OF ITS CORE WIRE. THE SIZE IS AVAILABLE IN METRIC AS WELL AS IN ENGLISH WIRE. THE SIZE IS AVAILABLE IN METRIC AS WELL AS IN ENGLISH SYSTEM. LIKE 1/8”, 3/32” AND 2 MM , 4 MM ETC.SYSTEM. LIKE 1/8”, 3/32” AND 2 MM , 4 MM ETC.

STRIKING END CORE

BARE END FOR GRIPPING

FLUX OR COVERING

Dd

D = COVERING DIA , d= CORE DIA


Arc welding electrodes are classified Arc welding electrodes are classified in groups by American Welding in groups by American Welding Society (AWS a5.1-91) based upon Society (AWS a5.1-91) based upon their type of coating, mechanical their type of coating, mechanical properties and performance properties and performance characteristicscharacteristics as well as weld as well as weld metal chemistry. for our discussion metal chemistry. for our discussion we can categorize the electrode as we can categorize the electrode as under .under .

TYPES OF ELECTRODETYPES OF ELECTRODE


ELECTRODES TYPES ELECTRODES TYPES

ELECTRODEELECTRODE

BASED UPON MATERIALS BASED UPON COATING


BASED UPON MATERIALS BASED UPON MATERIALS

MILD STEEL ELECTRODES (AWS A5.1)MILD STEEL ELECTRODES (AWS A5.1) LOW ALLOY STEEL ELECTRODES (AWS A5.5)LOW ALLOY STEEL ELECTRODES (AWS A5.5) STAINLESS STEEL ELECTRODES (AWS A5.4)STAINLESS STEEL ELECTRODES (AWS A5.4) ELECTRODES FOR CAST IRON (AWS A5.15)ELECTRODES FOR CAST IRON (AWS A5.15) COPPER AND COPPER ALLOY ELECTRODECOPPER AND COPPER ALLOY ELECTRODE

(AWSA5.6(AWSA5.6)) NICKEL AND NICKEL ALLOY ELECTRODENICKEL AND NICKEL ALLOY ELECTRODE

((AWS A5.11)AWS A5.11) ALUMINIUM AND ALUMINIUM ALLOY ELECTRODE ALUMINIUM AND ALUMINIUM ALLOY ELECTRODE ((AWS A5.3)AWS A5.3)

ONLY FIRST THREE OF THE ABOVE WILL BE ONLY FIRST THREE OF THE ABOVE WILL BE DISCUSSED.DISCUSSED.


MILD STEEL ELECTRODESMILD STEEL ELECTRODES

AMERICAN WELDING SOCIETY SPECIFICATION AMERICAN WELDING SOCIETY SPECIFICATION AWS 5.1 DESCRIBES THE REQUIREMENTS FORAWS 5.1 DESCRIBES THE REQUIREMENTS FOR MILD STEEL ELECTRODES. AN IDENTIFICATION MILD STEEL ELECTRODES. AN IDENTIFICATION

SYSTEM HAS ADOPTED IN ORDER TO KNOW THE SYSTEM HAS ADOPTED IN ORDER TO KNOW THE PROPERTIES AND CHEMISTRY OF THE PROPERTIES AND CHEMISTRY OF THE ELECTRODE. THE IDENTIFICATION HAS ELECTRODE. THE IDENTIFICATION HAS EXPLAINED AS UNDER.EXPLAINED AS UNDER.

EXXXXEXXXX““E” DESIGNATES FOR ELECTRODEE” DESIGNATES FOR ELECTRODE


EEXXXXXXXX FIRST TWO NUMBERS FIRST TWO NUMBERS REFER TO REFER TO TENSILE STRENGTHTENSILE STRENGTH OF OF THE DEPOSITED WELD METAL. THE DEPOSITED WELD METAL.

FOR EXAMPLE : EFOR EXAMPLE : E60601010

“ “60”60” MEANS 60, 000 PSI TENSILE MEANS 60, 000 PSI TENSILE STRENGTH OF THE DEPOSITED STRENGTH OF THE DEPOSITED

WELD WELD METAL. METAL.


EXX EXX XX X X THIRD NUMBER IS DENOTINGTHIRD NUMBER IS DENOTING THETHE POSITIONPOSITION IN WHICH THE IN WHICH THE ELECTRODE CAN BE USEDELECTRODE CAN BE USED..

EXAMPLE: EXAMPLE: ““1” 1” FOR ALL POSTION (F, V,OH,H)FOR ALL POSTION (F, V,OH,H) ““2” 2” FOR FLAT AND H-FILLET POSITIONFOR FLAT AND H-FILLET POSITION.. ““3” 3” HAS NO DESIGNATIONHAS NO DESIGNATION ““4” 4” FOR F, OH, H AND V-DOWN BUT FOR F, OH, H AND V-DOWN BUT

MOSTLY SUITABLE FOR V-DOWN MOSTLY SUITABLE FOR V-DOWN ONLY.ONLY.


EXXEXXXXXX LAST NUMBER REFERS TO LAST NUMBER REFERS TO CHEMICAL COMPOSITIONCHEMICAL COMPOSITION PRESENT IN THE ELECTRODE PRESENT IN THE ELECTRODE COATING. FOR EXAMPLE :COATING. FOR EXAMPLE :

““0”0” CELLULOSE- SODIUMCELLULOSE- SODIUM ““1”1” CELLULOSE- POTASSIUMCELLULOSE- POTASSIUM ““2”2” RUTILE –SODIUMRUTILE –SODIUM ““3”3” RUTILE – POTASSIUMRUTILE – POTASSIUM ““4”4” RUTILE IRON POWDERRUTILE IRON POWDER ““5,6,8”5,6,8” LOW HYDROGEN LOW HYDROGEN


EXXEXXXX XX The last two numbers together The last two numbers together indicate the type of welding current the indicate the type of welding current the electrode can be used with. electrode can be used with. For example For example

EXXEXX1010 DC+ DC+EXXEXX1111 AC OR DC+ AC OR DC+ EXX EXX2020 AC , DC +,-AC , DC +,-EXXEXX1212 AC OR DC- AC OR DC- EXX EXX2424 AC , DC +,-AC , DC +,-EXXEXX1313 AC , DC+,- AC , DC+,- EXX EXX2727 AC, DC +,-AC, DC +,-EXXEXX1414 AC , DC+,- AC , DC+,- EXX EXX2828 AC, DC +AC, DC +EXXEXX1515 DC+DC+ EXXEXX1616 AC , DC+AC , DC+EXXEXX1818 AC , DC+ AC , DC+


LOW ALLOY STEEL ELECTRODELOW ALLOY STEEL ELECTRODE

THESE ELECTRODES ARE DESIGNED FOR THE THESE ELECTRODES ARE DESIGNED FOR THE WELDING OF LOW-ALLOY STEELS COMMONLY USED WELDING OF LOW-ALLOY STEELS COMMONLY USED IN STRUCTURES, PIPING, PRESSURE VESSEL.IN STRUCTURES, PIPING, PRESSURE VESSEL.

THEY GIVE WELD DEPOSITS OF STEEL CONTAINING THEY GIVE WELD DEPOSITS OF STEEL CONTAINING A SMALL AMOUNT OF ALLOYING ELEMENTS SUCH A SMALL AMOUNT OF ALLOYING ELEMENTS SUCH AS Mo, Cr, Ni, AND V. THESE ELECTRODES ARE AS Mo, Cr, Ni, AND V. THESE ELECTRODES ARE SPECIFIED IN AWS A5.5 SPECIFICATION AND SPECIFIED IN AWS A5.5 SPECIFICATION AND IDENTIFICATION IS SAME AS FOR MILD STEEL IDENTIFICATION IS SAME AS FOR MILD STEEL ELECTRODES.THE ELECTRODES HAS A SUFFIX TO ELECTRODES.THE ELECTRODES HAS A SUFFIX TO REFER AS LOW ALLOY STEEL CONTENT. LIKE REFER AS LOW ALLOY STEEL CONTENT. LIKE

A1 0.5 Mo, B3 1.0% Mo,2.25%Mn , G 0.2% Mo, A1 0.5 Mo, B3 1.0% Mo,2.25%Mn , G 0.2% Mo, 0.3%Mn, 0.1% V0.3%Mn, 0.1% V


STAINLESS STEEL ELECTRODESSTAINLESS STEEL ELECTRODES

STAINLESS STEEL ELECTRODES ARE USED FOR STAINLESS STEEL ELECTRODES ARE USED FOR THE WELDING OF CORROSION –RESISTING AND THE WELDING OF CORROSION –RESISTING AND HEAT- RESISTING STEELS. THEY ARE EXPLIANED HEAT- RESISTING STEELS. THEY ARE EXPLIANED IN AWS A5.4 “SPECIFICATION FOR CORROSION –IN AWS A5.4 “SPECIFICATION FOR CORROSION –RESISTING Cr AND Cr-Ni STEEL COVERED RESISTING Cr AND Cr-Ni STEEL COVERED ELECTRODES”. ELECTRODES”.

SOME SS ELECTRODES HAVE GIVEN WITH THEIR SOME SS ELECTRODES HAVE GIVEN WITH THEIR MECHANICAL PROPERTIES IN THE FOLLOWING MECHANICAL PROPERTIES IN THE FOLLOWING TABLE.TABLE.


Mechanical Properties As Per AWSMechanical Properties As Per AWS A5.4A5.4AWS AWS ClassificatioClassificationn

Tensile Tensile StrengthStrength

KsiKsi

Elongation Elongation in 2” Min in 2” Min %%

Heat TreatmentHeat Treatment

E209E209 100100 1515 None None

E308LE308L 7575 3535 None None

E309LE309L 8080 3030 None None

E316E316 7575 3030 None None

E316HE316H 7575 3030 None None

E316LE316L 7070 3030 NoneNone

E317E317 8080 3030 None None

E318E318 8080 3030 None None


BASED UPON COATING BASED UPON COATING

CELLULOS TYPE CELLULOS TYPE RUTILE TYPE RUTILE TYPE ACID TYPE ACID TYPE OXIDIZING TYPE OXIDIZING TYPE BASIC TYPE BASIC TYPE


CELLULOS TYPE CELLULOS TYPE

THE CELLULOSE IS A ORGANIC MATERIAL THE CELLULOSE IS A ORGANIC MATERIAL WHICH CONTAIN 30 % IN THE ELECTRODE WHICH CONTAIN 30 % IN THE ELECTRODE COATING BY WEIGHT. IT DECOMPOSES IN THE COATING BY WEIGHT. IT DECOMPOSES IN THE ARC AND PRODUCE A GAS SHIELD WHICH ARC AND PRODUCE A GAS SHIELD WHICH PROTECTS ARC FROM AUTMOSPHERIC OXYGEN PROTECTS ARC FROM AUTMOSPHERIC OXYGEN AND NITROGEN. EXX10 IS THE EXAMPLE OF THIS AND NITROGEN. EXX10 IS THE EXAMPLE OF THIS TYPE ELECTRODE COATING. GENERALLY THIS TYPE ELECTRODE COATING. GENERALLY THIS COATED ELECTRODE IS SUITABLE FOR ALL COATED ELECTRODE IS SUITABLE FOR ALL POSITION WITH DC +. POSITION WITH DC +.


RUTILE TYPE RUTILE TYPE

RUTILE IS NATURALLY- OCCURING SAND USALLY RUTILE IS NATURALLY- OCCURING SAND USALLY CONTAIN AROUND 95% OF TITANIUM DIOXIDE. CONTAIN AROUND 95% OF TITANIUM DIOXIDE. THIS TYPE OF ELECTRODE IS GOOD FOR USE THIS TYPE OF ELECTRODE IS GOOD FOR USE WITH AC AND DC + OR DC - . GENERALLY USE WITH AC AND DC + OR DC - . GENERALLY USE FOR VERTICAL AND OVERHEAD POSITIONS AS FOR VERTICAL AND OVERHEAD POSITIONS AS THE SLAG IS VERY VISCOUS AND QUICKLY THE SLAG IS VERY VISCOUS AND QUICKLY FREEZED. EXX12 AND EXX13 ARE THE EXAMPLES FREEZED. EXX12 AND EXX13 ARE THE EXAMPLES OF THIS TYPE OF COATING .OF THIS TYPE OF COATING .


ACID TYPE ACID TYPE

THIS TYPE OF COATING CONTAIN IRON-OXIDE AS THIS TYPE OF COATING CONTAIN IRON-OXIDE AS A MAJOR CONSTITUENT. DURING WELDING IT A MAJOR CONSTITUENT. DURING WELDING IT PRODUCE A IRON-MANGANESE OXIDE –SELICA PRODUCE A IRON-MANGANESE OXIDE –SELICA FLUID SLAG WHOSE METALLARGICAL EFFECT IS FLUID SLAG WHOSE METALLARGICAL EFFECT IS ACIDIC. THIS SLAG SOLIDIFIES LIKE HONEY- ACIDIC. THIS SLAG SOLIDIFIES LIKE HONEY- COMBSTRUCTURE AND EASLY DETACHED. COMBSTRUCTURE AND EASLY DETACHED. ELECTRODE HAVING THIS COATING IS GOOD FOR ELECTRODE HAVING THIS COATING IS GOOD FOR FILLET WELD ONLY. FILLET WELD ONLY.

EXX22 IS THE EXAMPLE OF THIS TYPE OF EXX22 IS THE EXAMPLE OF THIS TYPE OF ELECTRODE.ELECTRODE.


OXIDIZING TYPE OXIDIZING TYPE

IT CONTAIN MAINLY IRON-OXIDE AND IT CONTAIN MAINLY IRON-OXIDE AND SILICATES WITH OR WITH OUT MANGANESE SILICATES WITH OR WITH OUT MANGANESE OXIDES. IT PRODUCE A HEAVY SLAG WHICH OXIDES. IT PRODUCE A HEAVY SLAG WHICH HAS OXIDISING PROPERTIES. THIS TYPE HAS OXIDISING PROPERTIES. THIS TYPE ELECTRODE IS LIMITED IN USE BECAUSE ELECTRODE IS LIMITED IN USE BECAUSE THE RESULTANT WELD METAL IS SOFT AND THE RESULTANT WELD METAL IS SOFT AND LOW MECHANICAL PROPERTIES. LOW MECHANICAL PROPERTIES.

EXX27 ELECTRODES ARE HAVING THIS TYPE EXX27 ELECTRODES ARE HAVING THIS TYPE OF COATING, GENERALLY USING FOR FLAT OF COATING, GENERALLY USING FOR FLAT POSITION ONLY. POSITION ONLY.


BASIC TYPE BASIC TYPE

THIS TYPE OF COATING CONTAINS CALCIUM CARBONATES THIS TYPE OF COATING CONTAINS CALCIUM CARBONATES (CaCO3), CALCIUM FLOURIDE (CaF2) , METAL POWDER AND (CaCO3), CALCIUM FLOURIDE (CaF2) , METAL POWDER AND COMPARATIVELY MORE POWERFUL DEOXIDISERS. COMPARATIVELY MORE POWERFUL DEOXIDISERS. THIS RESULTS IN A CHEMICALLY BASIC SLAG, WHICH IS THIS RESULTS IN A CHEMICALLY BASIC SLAG, WHICH IS FAIRLY FLUID.THE SOLIDIFIED SLAG, WHICH IS HEAVY AND FAIRLY FLUID.THE SOLIDIFIED SLAG, WHICH IS HEAVY AND FRIABLE HAS BROWN TO DARK- BROWN COLOR AND FRIABLE HAS BROWN TO DARK- BROWN COLOR AND GLASSY APPEARANCE. GLASSY APPEARANCE. MOISTURES IS REMOVED FROM THE COATING TO RENDER MOISTURES IS REMOVED FROM THE COATING TO RENDER IT LOW HYDROGEN ELECTRODES. THE ELECTRODES IT LOW HYDROGEN ELECTRODES. THE ELECTRODES HAVING THIS TYPE OF COATING IS PREFERRED TO USE FOR HAVING THIS TYPE OF COATING IS PREFERRED TO USE FOR MINIMISE THE RISK OF HYDROGEN-INDUCED CRACKING OR MINIMISE THE RISK OF HYDROGEN-INDUCED CRACKING OR COLD CRACKING IN THE BASE METAL. COLD CRACKING IN THE BASE METAL.

EXX15,16,18 OR THE EXAMPLES OF THIS TYPE OF EXX15,16,18 OR THE EXAMPLES OF THIS TYPE OF COATING.COATING.


STORAGE AND DRYING OF STORAGE AND DRYING OF ELECTRODE ELECTRODE

Arc welding electrodes must be properly Arc welding electrodes must be properly stored in order to deposit quality welds. when stored in order to deposit quality welds. when electrodes absorb moistures from the electrodes absorb moistures from the atmosphere, they must be dried in order to atmosphere, they must be dried in order to restore the ability to deposit quality welds. restore the ability to deposit quality welds. Electrode with too much moisture may lead toElectrode with too much moisture may lead to

Cracking and Porosity. Operational Cracking and Porosity. Operational characteristics may be affected as well. If it is characteristics may be affected as well. If it is experienced unexplained weld cracking experienced unexplained weld cracking problems, or if the electrode arc performance problems, or if the electrode arc performance may have deteriorated, it may be due to the may have deteriorated, it may be due to the storage methods or re-drying proceduresstorage methods or re-drying procedures. .


All electrodes must be All electrodes must be dried to the right level dried to the right level to perform properly. to perform properly. Even a small amount Even a small amount of moisture in low of moisture in low hydrogen electrodes hydrogen electrodes can lead to major weld can lead to major weld problems such as problems such as internal porosity, weld internal porosity, weld cracking or poor cracking or poor operating operating characteristics. characteristics.


Low Hydrogen ElectrodesLow Hydrogen Electrodes

Storing and exposure limitsStoring and exposure limitsSMAW electrodes with low hydrogen SMAW electrodes with low hydrogen coatings, such as E7018 and E8018-coatings, such as E7018 and E8018-C3, must be kept very dry since C3, must be kept very dry since hydrogen induced cracking can hydrogen induced cracking can easily occur, especially in steels that easily occur, especially in steels that are 80,000 psi and higher yield are 80,000 psi and higher yield strengths. To keep these electrodes strengths. To keep these electrodes dry during storage, here are some dry during storage, here are some suggestions: suggestions:


Purchase these electrodes in Purchase these electrodes in hermetically sealed containers, which hermetically sealed containers, which provide excellent protection against provide excellent protection against moisture pickup. moisture pickup.

Do not open the hermetically sealed Do not open the hermetically sealed containers until the electrode is needed containers until the electrode is needed for use. for use.

When the cans are opened, electrodes When the cans are opened, electrodes that will not be immediately used should that will not be immediately used should be placed in a OVEN at 250 degrees F to be placed in a OVEN at 250 degrees F to 300 degrees F 300 degrees F

(120 – 150 degrees C). (120 – 150 degrees C).


Electrodes should be supplied to Electrodes should be supplied to welders in quantities that can be welders in quantities that can be consumed within time limits that are consumed within time limits that are dependent on the electrode type and dependent on the electrode type and strength level. For example, standard strength level. For example, standard E7018 electrodes can be safely be E7018 electrodes can be safely be exposed to the atmosphere for 4 exposed to the atmosphere for 4 hours whereas standard E11018 hours whereas standard E11018 electrodes are restricted to only ½ electrodes are restricted to only ½ hour. hour.


Re-drying Of Low Hydrogen ElectrodesRe-drying Of Low Hydrogen Electrodes When the electrodes have been exposed to When the electrodes have been exposed to

the atmosphere for period of a four hours , the atmosphere for period of a four hours , the electrode can be re-dried. The following the electrode can be re-dried. The following re-drying procedure should be used: re-drying procedure should be used:

To re-dry, electrodes should be removed To re-dry, electrodes should be removed from the can, and placed in suitable oven. from the can, and placed in suitable oven. The electrodes should be spread out in the The electrodes should be spread out in the oven so that all electrodes will reach the oven so that all electrodes will reach the drying temperature. The can of electrodes drying temperature. The can of electrodes should not be put in the oven; the cardboard should not be put in the oven; the cardboard liners can char, and the temperature of the liners can char, and the temperature of the electrodes will not be uniform. electrodes will not be uniform.


BAKING OVEN

TEMPERATURE REGULATOR


POTABLE OVEN


When the electrodes are initially placed in the When the electrodes are initially placed in the oven, the temperature should not be greater oven, the temperature should not be greater than half the re-drying temperature. The than half the re-drying temperature. The electrodes should be held at that temperature electrodes should be held at that temperature for ½ hour before heating the electrode to the for ½ hour before heating the electrode to the final temperature. final temperature.

For mild steel low hydrogen electrodes For mild steel low hydrogen electrodes governed by governed by AWS A5.1AWS A5.1 (such as E7018), the (such as E7018), the final re-drying temperature is typically 500-final re-drying temperature is typically 500-800 degrees F(260-430 degrees C). For low 800 degrees F(260-430 degrees C). For low alloy electrodes governed by alloy electrodes governed by AWS A5.5AWS A5.5, the , the final re-drying temperature should be 700-final re-drying temperature should be 700-800 degrees F (700 – 430 degrees C). The 800 degrees F (700 – 430 degrees C). The manufacturer’s recommendations should be manufacturer’s recommendations should be followed. followed.


One hour at the listed final One hour at the listed final temperature is satisfactory if it is temperature is satisfactory if it is supplied in the dried condition. Do not supplied in the dried condition. Do not dry electrodes at higher temperatures. dry electrodes at higher temperatures. Also, several hours at a lower Also, several hours at a lower temperature is not equivalent to using temperature is not equivalent to using the specified requirements. Moisture the specified requirements. Moisture becomes chemically bonded becomes chemically bonded (absorbed) to the electrode coating (absorbed) to the electrode coating and those chemical bonds must be and those chemical bonds must be broken at the proper temperature for broken at the proper temperature for the proper length of time. the proper length of time.


How Many Times Low Hydrogen How Many Times Low Hydrogen Electrodes Can Be Re-dried?Electrodes Can Be Re-dried?

Electrodes may be re-dried only Electrodes may be re-dried only once. Electrodes that have become once. Electrodes that have become wet or moist shall not be used and wet or moist shall not be used and shall be discarded.shall be discarded.


Standard Tests For ElectrodesStandard Tests For Electrodes

Type Of Type Of TestTest

ISO ISO 25602560

BS639BS639 DINDIN

19131913AWS AWS A5.1A5.1

TENSILE & TENSILE & IMPACTIMPACT

XX XX XX XX

TRANSVERSE TRANSVERSE BEND BEND XX XX XX

TRANSVERSE TRANSVERSE TENSILETENSILE

XX XX XX

DEPOSITION DEPOSITION EFFECIENCYEFFECIENCY XX

DIFFUSIBLE DIFFUSIBLE HYDROGENHYDROGEN XX

CHEMICAL CHEMICAL COMPOSITIOCOMPOSITIONN

XX


THE ENDTHE END

THANKS THANKS

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